US20090045006A1 - Noise Eliminator for Fuel Cell - Google Patents
Noise Eliminator for Fuel Cell Download PDFInfo
- Publication number
- US20090045006A1 US20090045006A1 US11/920,432 US92043206A US2009045006A1 US 20090045006 A1 US20090045006 A1 US 20090045006A1 US 92043206 A US92043206 A US 92043206A US 2009045006 A1 US2009045006 A1 US 2009045006A1
- Authority
- US
- United States
- Prior art keywords
- inner pipe
- noise eliminator
- sound transmission
- exhaust gas
- fuel cell
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- 239000000446 fuel Substances 0.000 title claims abstract description 82
- 230000005540 biological transmission Effects 0.000 claims abstract description 256
- 230000002093 peripheral effect Effects 0.000 claims abstract description 82
- 239000011358 absorbing material Substances 0.000 claims abstract description 54
- 238000007599 discharging Methods 0.000 claims abstract description 17
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 95
- 238000011144 upstream manufacturing Methods 0.000 claims description 59
- 230000003014 reinforcing effect Effects 0.000 claims description 6
- 230000003116 impacting effect Effects 0.000 claims description 5
- 238000002347 injection Methods 0.000 claims description 5
- 239000007924 injection Substances 0.000 claims description 5
- 239000007789 gas Substances 0.000 abstract description 142
- 210000004027 cell Anatomy 0.000 description 42
- 230000015572 biosynthetic process Effects 0.000 description 26
- 230000001590 oxidative effect Effects 0.000 description 22
- 230000002940 repellent Effects 0.000 description 9
- 239000005871 repellent Substances 0.000 description 9
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 8
- 230000008030 elimination Effects 0.000 description 6
- 238000003379 elimination reaction Methods 0.000 description 6
- 239000001257 hydrogen Substances 0.000 description 5
- 229910052739 hydrogen Inorganic materials 0.000 description 5
- 229920003002 synthetic resin Polymers 0.000 description 5
- 239000000057 synthetic resin Substances 0.000 description 5
- 210000005056 cell body Anatomy 0.000 description 4
- 239000002737 fuel gas Substances 0.000 description 4
- 238000010521 absorption reaction Methods 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 3
- 239000007788 liquid Substances 0.000 description 3
- 230000001629 suppression Effects 0.000 description 3
- 230000001133 acceleration Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 229910052731 fluorine Inorganic materials 0.000 description 2
- 239000011491 glass wool Substances 0.000 description 2
- 238000005192 partition Methods 0.000 description 2
- 238000000638 solvent extraction Methods 0.000 description 2
- YCKRFDGAMUMZLT-UHFFFAOYSA-N Fluorine atom Chemical compound [F] YCKRFDGAMUMZLT-UHFFFAOYSA-N 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000002238 attenuated effect Effects 0.000 description 1
- 230000005494 condensation Effects 0.000 description 1
- 238000009833 condensation Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 239000003792 electrolyte Substances 0.000 description 1
- 239000011737 fluorine Substances 0.000 description 1
- 230000001771 impaired effect Effects 0.000 description 1
- 238000001746 injection moulding Methods 0.000 description 1
- 230000002452 interceptive effect Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 230000001902 propagating effect Effects 0.000 description 1
- 238000010926 purge Methods 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N1/00—Silencing apparatus characterised by method of silencing
- F01N1/02—Silencing apparatus characterised by method of silencing by using resonance
- F01N1/04—Silencing apparatus characterised by method of silencing by using resonance having sound-absorbing materials in resonance chambers
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N1/00—Silencing apparatus characterised by method of silencing
- F01N1/08—Silencing apparatus characterised by method of silencing by reducing exhaust energy by throttling or whirling
- F01N1/083—Silencing apparatus characterised by method of silencing by reducing exhaust energy by throttling or whirling using transversal baffles defining a tortuous path for the gases or successively throttling gas flow
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N1/00—Silencing apparatus characterised by method of silencing
- F01N1/08—Silencing apparatus characterised by method of silencing by reducing exhaust energy by throttling or whirling
- F01N1/085—Silencing apparatus characterised by method of silencing by reducing exhaust energy by throttling or whirling using a central core throttling gas passage
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N1/00—Silencing apparatus characterised by method of silencing
- F01N1/08—Silencing apparatus characterised by method of silencing by reducing exhaust energy by throttling or whirling
- F01N1/086—Silencing apparatus characterised by method of silencing by reducing exhaust energy by throttling or whirling having means to impart whirling motion to the gases
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N1/00—Silencing apparatus characterised by method of silencing
- F01N1/08—Silencing apparatus characterised by method of silencing by reducing exhaust energy by throttling or whirling
- F01N1/10—Silencing apparatus characterised by method of silencing by reducing exhaust energy by throttling or whirling in combination with sound-absorbing materials
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M8/00—Fuel cells; Manufacture thereof
- H01M8/06—Combination of fuel cells with means for production of reactants or for treatment of residues
- H01M8/0662—Treatment of gaseous reactants or gaseous residues, e.g. cleaning
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N2240/00—Combination or association of two or more different exhaust treating devices, or of at least one such device with an auxiliary device, not covered by indexing codes F01N2230/00 or F01N2250/00, one of the devices being
- F01N2240/20—Combination or association of two or more different exhaust treating devices, or of at least one such device with an auxiliary device, not covered by indexing codes F01N2230/00 or F01N2250/00, one of the devices being a flow director or deflector
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N2240/00—Combination or association of two or more different exhaust treating devices, or of at least one such device with an auxiliary device, not covered by indexing codes F01N2230/00 or F01N2250/00, one of the devices being
- F01N2240/32—Combination or association of two or more different exhaust treating devices, or of at least one such device with an auxiliary device, not covered by indexing codes F01N2230/00 or F01N2250/00, one of the devices being a fuel cell
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N2470/00—Structure or shape of gas passages, pipes or tubes
- F01N2470/02—Tubes being perforated
- F01N2470/04—Tubes being perforated characterised by shape, disposition or dimensions of apertures
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N2470/00—Structure or shape of gas passages, pipes or tubes
- F01N2470/20—Dimensional characteristics of tubes, e.g. length, diameter
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
- F01N2510/00—Surface coverings
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/30—Hydrogen technology
- Y02E60/50—Fuel cells
Definitions
- the present invention relates to a structure providing countermeasures against condensation of moisture in exhaust gas with respect to a noise eliminator installed in an exhaust system of fuel cell.
- a power generating reaction between fuel gas supplied to the anode electrode and oxidizing gas supplied to the cathode electrode occurs in an electrolyte, in conjunction with moisture is produced.
- the produced moisture is discharged as fuel cell exhaust gas, along with unused fuel gas and oxidizing gas, through an exhaust system connected to the fuel cell.
- the gas stream may produce a sound of a relatively high frequency, on the order of 500 Hz to 2000 Hz.
- the exhaust system of a fuel cell vehicle or the like is typically equipped with a sound absorption type noise eliminator whose interior is packed with a sound absorbing material (noise elimination material) such as glass wool.
- This noise eliminator 100 includes an inner pipe 102 through which the exhaust gas from the fuel cell flows, and an outer shell 104 surrounding the inner pipe 102 .
- a sound absorbing material 106 such as glass wool is filled between the inner pipe 102 and outer shell 104 .
- a plurality of sound transmission holes 108 are formed in the peripheral wall of the inner pipe 102 . The sound radiated from the sound transmission holes 108 toward the sound absorbing material 106 is attenuated while subjected to repeated scattering and interference in the sound absorbing material 106 , and is consequently absorbed by the sound absorbing material 106 .
- fuel cell exhaust gases contain a large amount of moisture produced by the reaction of hydrogen and oxygen.
- This moisture may condense in the exhaust system upstream to form liquid water which flows into the noise eliminator, or the moisture may condense in the interior of the noise eliminator.
- water may accumulate in the vertical lower part (hereinafter referred to as the bottom part) of the noise eliminator.
- the sound absorbing material filled in the bottom part of the noise eliminator absorbs and holds the water (“contains water”), a specified sound absorption performance cannot be achieved, and, thus, noise elimination performance is impaired.
- the noise eliminator 120 proposed in Japanese Patent Laid-Open Publication No. 2002-206413.
- the interior of the noise eliminator 120 is vertically partitioned into upper and lower parts by a partition board 124 having a continuous hole 123 , whereby a sound absorbing chamber 126 and expansion chamber 128 are formed.
- An inner pipe 130 having sound transmission holes 136 is arranged inside the sound absorbing chamber 126 , and a sound absorbing material is filled to surround the inner pipe 130 .
- a noise eliminator for a fuel cell includes an inner pipe having a plurality of sound transmission holes formed in a peripheral wall thereof and allowing exhaust gas to flow therethrough, and an outer shell, arranged to surround the inner pipe through a prescribed distance from the peripheral wall, and constituting a sound absorbing chamber with a sound absorbing material filled in a space between the outer shell and the inner pipe.
- the shape of the sound transmission holes is configured so that no liquid film is formed in the holes. Also, the shape of the sound transmission hole can be construed to have a function of reducing liquid surface tension in the hole.
- the noise eliminator for a fuel cell according to the present invention has the following configurations.
- a noise eliminator for a fuel cell is characterized by including an inner pipe having a plurality of sound transmission holes formed in a peripheral wall thereof and allowing exhaust gas to flow therethrough, and an outer shell, arranged to surround the inner pipe through a prescribed distance from the peripheral wall, and constituting a sound absorbing chamber with a sound absorbing material filled in a space between the outer shell and the inner pipe, wherein the sound transmission hole has an inner diameter of 3 mm or longer and a depth of 1.2 mm or shorter.
- the peripheral part of the sound transmission hole in the inner pipe is preferably formed thinner in wall thickness than the other part thereof.
- a rib reinforcing the inner pipe is preferably formed between the sound transmission holes.
- a noise eliminator for a fuel cell is characterized by including an inner pipe having a plurality of sound transmission holes formed in a peripheral wall thereof and allowing exhaust gas to flow therethrough, and an outer shell, arranged to surround the inner pipe through a prescribed distance from the peripheral wall, and constituting a sound absorbing chamber with a sound absorbing material filled in a space between the outer shell and the inner pipe, wherein the sound transmission hole is formed in the shape of an oval having a longitudinal axis along the axis direction of the inner pipe.
- a noise eliminator for a fuel cell is characterized by including an inner pipe having a plurality of sound transmission holes formed in a peripheral wall thereof and allowing exhaust gas to flow therethrough, and an outer shell, arranged to surround the inner pipe through a prescribed distance from the peripheral wall, and constituting a sound absorbing chamber with a sound absorbing material filled in a space between the outer shell and the inner pipe, wherein there is formed a groove connecting the adjoining sound transmission holes.
- a noise eliminator for a fuel cell is characterized by including an inner pipe having a plurality of sound transmission holes formed in a peripheral wall thereof and allowing exhaust gas to flow therethrough, and an outer shell, arranged to surround the inner pipe through a prescribed distance from the peripheral wall, and constituting a sound absorbing chamber with a sound absorbing material filled in a space between the outer shell and the inner pipe, wherein the inner wall of the sound transmission hole is formed with a saw-tooth shape.
- a noise eliminator for a fuel cell is characterized by including an inner pipe having a plurality of sound transmission holes formed in a peripheral wall thereof and allowing exhaust gas to flow therethrough, and an outer shell, arranged to surround the inner pipe through a prescribed distance from the peripheral wall, and constituting a sound absorbing chamber with a sound absorbing material filled in a space between the outer shell and the inner pipe, wherein a water repellant layer is formed in the inner wall of the sound transmission hole.
- a noise eliminator for a fuel cell is characterized by including an inner pipe having a plurality of sound transmission holes formed in a peripheral wall thereof and allowing exhaust gas to flow therethrough, and an outer shell, arranged to surround the inner pipe through a prescribed distance from the peripheral wall, and constituting a sound absorbing chamber with a sound absorbing material filled in a space between the outer shell and the inner pipe, wherein a sound absorbing material is filled in the inner side of the inner wall of the sound transmission hole.
- a noise eliminator for a fuel cell is characterized by including an inner pipe having a plurality of sound transmission holes formed in a peripheral wall thereof and allowing exhaust gas to flow therethrough, and an outer shell, arranged to surround the inner pipe through a prescribed distance from the peripheral wall, and constituting a sound absorbing chamber with a sound absorbing material filled in a space between the outer shell and the inner pipe, wherein the inner pipe is provided with a drift member drifting an exhaust gas stream so that the exhaust gas stream is prevented from directly impacting the sound transmission hole.
- the drift member is preferably a louver protruding in a manner inclined from an upstream end of the sound transmission hole to a downstream direction in the inner-pipe inner wall.
- the drift member may be arranged in the inner wall of an upstream portion of the inner pipe, being preferably a stream guide plate which guides exhaust gas to an area where no sound transmission hole is formed.
- a noise eliminator for a fuel cell according to the present invention is characterized by including a swirling stream generation member for generating a swirling stream along the inner pipe inner wall, the member being disposed upstream in the inner pipe.
- a noise eliminator for a fuel cell is characterized by including an inner pipe having a plurality of sound transmission holes formed in a peripheral wall thereof and allowing exhaust gas to flow therethrough, and an outer shell, arranged to surround the inner pipe through a prescribed distance from the peripheral wall, and constituting a sound absorbing chamber with a sound absorbing material filled in a space between the outer shell and the inner pipe, wherein a vortex generation member generating a vortex in the vicinity of the inner-pipe inner wall is arranged in the inner pipe.
- a noise eliminator for a fuel cell is characterized by including stream guide means for causing a part of exhaust gas flowing into the inner pipe to flow out from inside the inner pipe through the upstream-side sound transmission holes to the sound absorbing chamber, wherein the exhaust gas flowing out to the sound absorbing chamber flows through the downstream-side sound transmission holes back into the inner pipe.
- the stream guide means may be a narrowed portion formed in the path of the inner pipe, or the stream guide means may be a duct arranged in the inner-pipe inner wall in a manner corresponding to the upstream-side sound transmission hole.
- a noise eliminator for a fuel cell is characterized by including an inner pipe having a plurality of sound transmission holes formed in a peripheral wall thereof and allowing exhaust gas to flow therethrough, and an outer shell, arranged to surround the inner pipe through a prescribed distance from the peripheral wall, and constituting a sound absorbing chamber with a sound absorbing material filled in a space between the outer shell and the inner pipe, the noise eliminator further including gas injection means for injecting gas from outside the noise eliminator directly to the sound absorbing chamber so that gas flows from the sound absorbing chamber through the sound transmission holes into the inner pipe.
- a noise eliminator for a fuel cell is characterized by including an inner pipe having a plurality of sound transmission holes formed in a peripheral wall thereof and allowing exhaust gas to flow therethrough, and an outer shell, arranged to surround the inner pipe through a prescribed distance from the peripheral wall, and constituting a sound absorbing chamber with a sound absorbing material filled in a space between the outer shell and the inner pipe, wherein the sound transmission hole and a peripheral part thereof are formed in a manner projecting toward the axis center of the inner pipe.
- a noise eliminator for a fuel cell is characterized by including an outer shell allowing exhaust gas to flow therethrough, and an inner case having a plurality of through holes formed in a peripheral wall thereof and constituting a sound absorbing chamber with a sound absorbing material filled in the interior thereof, wherein the inner case is arranged over the entire stream path cross section of the outer shell so that all the exhaust gas flowing through the outer shell flows through the interior of the inner case.
- a noise eliminator for a fuel cell is characterized by including a shell allowing exhaust gas to flow therethrough, and a plate-shaped member partitioning the interior of the shell by a face thereof orthogonal to the direction of exhaust gas stream and having a plurality of through holes formed therein.
- FIG. 1 is a vertical section of a noise eliminator according to a first embodiment of the present invention
- FIG. 2 is an expanded sectional view of an inner-pipe peripheral wall in the noise eliminator according to the first embodiment of the present invention, being an expanded sectional view of the portion A in FIG. 1 ;
- FIG. 3 is an expanded sectional view of an inner-pipe peripheral wall in a noise eliminator according to a variation of the first embodiment of the present invention, being an expanded sectional view of the portion A of FIG. 1 ;
- FIG. 4 is a vertical section of a noise eliminator according to another variation of the first embodiment of the present invention.
- FIG. 5 is a view of an inner pipe having a cross section illustrated in FIG. 4 , as seen from the direction indicated by the arrow D;
- FIG. 6 is a view illustrating a configuration of a sound transmission hole in a noise eliminator according to a second embodiment of the present invention.
- FIG. 7 is a view illustrating a configuration of a sound transmission hole in a noise eliminator according to a variation of the second embodiment of the present invention.
- FIG. 8 is a view illustrating a configuration of a sound transmission hole in a noise eliminator according to another variation of the second embodiment of the present invention.
- FIG. 9 is an expanded sectional view of an inner-pipe peripheral wall in a noise eliminator according to a third embodiment of the present invention, being an expanded sectional view of the portion A in FIG. 1 ;
- FIG. 10 is an expanded sectional view of an inner-pipe peripheral wall in a noise eliminator according to a fourth embodiment of the present invention, being an expanded sectional view of the portion A in FIG. 1 ;
- FIG. 11 is a vertical section of an inner pipe in a noise eliminator according to a fifth embodiment of the present invention.
- FIG. 12 is an expanded sectional view of the inner-pipe peripheral wall portion I in FIG. 11 ;
- FIG. 13 is a view of the inner pipe having a cross section illustrated in FIG. 11 , as seen from the direction indicated by the arrow D;
- FIG. 14 is a vertical section of an inner pipe in a noise eliminator according to a variation of the fifth embodiment of the present invention.
- FIG. 15 is a view schematically illustrating a vertical cross section of a noise eliminator according to a sixth embodiment of the present invention.
- FIG. 16 is a view schematically illustrating a vertical cross section of a noise eliminator according to a seventh embodiment of the present invention.
- FIG. 17 is a view illustrating an exemplary vortex generation member arranged in the noise eliminator according to the seventh embodiment of the present invention.
- FIG. 18 is a vertical section of an inner pipe in a noise eliminator according to a variation of the seventh embodiment of the present invention.
- FIG. 19 is a view of the inner pipe having a cross section illustrated in FIG. 18 , as seen from the direction indicated by the arrow D;
- FIG. 20 is a view schematically illustrating a vertical cross section of a noise eliminator according to an eighth embodiment of the present invention.
- FIG. 21 is a vertical section of an inner pipe in a noise eliminator according to a variation of the eighth embodiment of the present invention.
- FIG. 22 is a view of the inner pipe having a cross section illustrated in FIG. 21 , as seen from the direction indicated by the arrow D;
- FIG. 23 is a view schematically illustrating a noise eliminator according to a ninth embodiment of the present invention, and a peripheral device;
- FIG. 24 is a vertical section of a noise eliminator according to a tenth embodiment of the present invention.
- FIG. 25 is a view of the inner pipe having a cross section illustrated in FIG. 24 , as seen from the direction indicated by the arrow D;
- FIG. 26 is a view schematically illustrating a vertical cross section of a noise eliminator according to an eleventh embodiment of the present invention.
- FIG. 27 is a perspective view of an inner case in a noise eliminator according to the eleventh embodiment of the present invention.
- FIG. 28 is a vertical section of a noise eliminator according to a twelfth embodiment of the present invention.
- FIG. 29 is a view of a plate-shaped member in the noise eliminator according to the twelfth embodiment of the present invention, as seen from a direction indicated by the arrow D of FIG. 28 ;
- FIG. 30 is a view illustrating an exemplary schematic configuration of a fuel cell system
- FIG. 31 is a transverse sectional view of a sound absorption type noise eliminator.
- FIG. 32 is a vertical section of a noise eliminator described in Japanese Patent Laid-Open Publication No. 2002-206413.
- the fuel cell system 80 includes a fuel cell 82 , a hydrogen tank 84 supplying hydrogen gas to the fuel cell 82 , a blower 86 supplying oxidizing gas to the fuel cell 82 , and an exhaust system 88 (indicated by the two-dot chain line in FIG. 30 ) discharging exhaust gas from the fuel cell 82 .
- the hydrogen tank 84 is joined through a fuel gas supplying path 85 to the fuel cell 82 , and hydrogen gas (fuel gas) stored in the hydrogen tank 84 is supplied, after being subjected to flow rate adjustment by a regulator 90 , through a control valve 92 to the fuel cell 82 .
- the blower 86 is connected through an oxidizing gas supplying path 87 to the fuel cell 82 , whereby oxidizing gas (air) is supplied to the fuel cell 82 .
- the supplied hydrogen gas and air react to produce electric energy and at the same time produce moisture.
- Air unused in the reaction and oxidizing gas containing moisture (water vapor) produced in the fuel cell are discharged from the fuel cell 82 through a given exhaust system.
- the noise eliminator 10 is disposed at the tail end of this exhaust system; the exhaust gas containing moisture, and water being the result of moisture contained in exhaust gas condensing in the interior of the preceding exhaust system relative to the noise eliminator 10 flow from the upstream end of the exhaust system upstream (the end indicated by the arrow D of FIG. 1 ) into the noise eliminator 10 .
- the noise eliminator according to the present embodiment is arranged in the exhaust system of the above described fuel cell system. More specifically, the noise eliminator is installed as an exhaust sound noise elimination device (muffler) for a fuel cell vehicle in the underbody (not illustrated) towards the rear of the vehicle hung by a bracket or the like.
- the noise eliminator is installed as an exhaust sound noise elimination device (muffler) for a fuel cell vehicle in the underbody (not illustrated) towards the rear of the vehicle hung by a bracket or the like.
- FIG. 1 illustrates a vertical section configuration of the noise eliminator
- FIG. 2 illustrates an expanded sectional view of the section of the inner-pipe peripheral wall A in FIG. 1
- FIG. 3 illustrates an expanded sectional view of another example inner-pipe peripheral wall
- FIG. 4 illustrates a vertical section configuration of a another example noise eliminator
- FIG. 5 illustrates a view of an inner pipe having a cross section illustrated in FIG. 4 , as seen from the direction indicated by the arrow D.
- the noise eliminator 10 includes, as illustrated in FIG. 1 , an outer shell 12 constituting the outer covering of the noise eliminator and an inner pipe 14 , arranged within the outer shell 12 , and allowing exhaust gas to flow therethrough.
- a sound absorbing material 16 is filled between the inner pipe 14 and outer shell 12 , to thereby form a sound absorbing chamber 17 .
- the exhaust gas flowing from the exhaust system upstream side into the noise eliminator passes through the inner pipe 14 and is discharged to the outside of the noise eliminator 10 .
- the sound transmitted along with the exhaust gas from the exhaust system upstream side into the inner pipe 14 is radiated from sound transmission holes 18 arranged in a peripheral wall 13 of the inner pipe 14 toward the sound absorbing material 16 , and absorbed by the sound absorbing material 16 .
- the noise eliminator 10 achieves a given noise elimination performance.
- the inner pipe 14 is, as illustrated in FIG. 2 , constituted of an outer pipe section 20 having a plurality of sound transmission holes 18 formed in a peripheral wall 13 thereof, and an inner pipe section 22 , installed in the inner side of the peripheral wall 13 of the outer pipe section 20 , and reinforcing the outer pipe section 20 .
- the outer pipe section 20 is made of synthetic resin, the wall thickness (indicated by the size B in FIG. 2 ) thereof being 1.2 mm or smaller.
- the inner diameter of the sound transmission hole 18 (indicated by the size C in FIG. 2 ) being set to 3 mm or larger.
- the wall thickness of the inner pipe section 22 is formed larger than the outer pipe section 20 .
- the inner pipe section 22 there are formed a plurality of through holes 23 in a manner corresponding to that used to form the above described sound transmission holes 18 .
- the configuration of the through hole is designed so as not to seal the sound transmission hole 18 formed in the outer pipe section 20 when the inner pipe section 22 is installed in the outer pipe section 20 .
- the inner pipe 14 can be made of synthetic resin and have a desired stiffness, and sound transmission holes 18 having an inner diameter of 3 mm or greater and a depth of 1.2 mm or less can be formed in the peripheral wall of the inner pipe 14 .
- the word “depth” used herein refers to the length of the sound transmission hole 18 in the direction along the center axis of the sound transmission hole 18 indicated by the dashed line E in FIG. 2 , and the wall thickness of the part (the outer pipe section 20 in the present embodiment) in which the sound transmission holes are formed.
- the inner diameter of the sound transmission hole 18 is 3 mm or larger, the depth thereof is set to a sufficiently small value of 1.2 mm or less. While there is formed a water film having a size corresponding to the inner diameter of the sound transmission hole 18 , because the area of the inner wall of the sound transmission hole 18 holding the water film is small, it is not possible for the inner wall of the sound transmission hole 18 to retain the water film. Consequently, in the noise eliminator 10 of the present embodiment, even when water flowing in from the exhaust system upstream side or water condensing in the interior of the noise eliminator attaches to the sound transmission holes, formation of a water film in the sound transmission holes can be suppressed.
- the inner pipe section 22 reinforcing the outer pipe section 20 was inserted to the interior of the thin-walled outer pipe section 20 in which the sound transmission holes 18 are formed, but the structure of the inner pipe is not limited thereto.
- the inner pipe can also be implemented by various embodiments described below.
- the wall of the peripheral part 24 of the sound transmission hole 18 in the inner pipe 14 b is formed smaller than the other part 25 .
- the peripheral part 24 is a part adjoining to the inner wall of the sound transmission hole 18 in which the thickness closer to the inner wall of the sound transmission hole 18 is less than elsewhere.
- the wall thickness (indicated by the size B) is 1.2 mm or less.
- the peripheral part 24 can be formed by cutting or injection molding.
- the other part (indicated by reference numeral 25 in FIG. 3 ) which is at a longer distance from the sound transmission hole 18 than the peripheral part 24 , has a sufficiently larger wall thickness than the part in which the sound transmission hole 18 is formed.
- a rib 28 reinforcing the inner pipe 14 c is formed between the sound transmission holes 18 .
- the inner pipe 14 c there is formed a rib 28 protruding from the inner wall 15 toward the axis center (indicated by F in FIG. 4 ) of the inner pipe 14 c .
- This rib 28 is formed integrally with the inner pipe 14 c ; in the inner wall of the inner pipe 14 c are formed an axis-direction rib 28 a extending in a direction along the axis center of the inner pipe 14 c and a circular shaped rib 28 b extending in a circular shape in a direction orthogonal to the axis center of the inner pipe 14 c . These ribs 28 are formed between the sound transmission holes 18 so as to avoid interfering with the sound transmission holes formed in the inner pipe 14 c.
- the inner pipe 14 c is formed thinner to have a wall thickness of 1.2 mm or less; the sound transmission hole 18 is formed in this part.
- FIG. 6 illustrates a configuration of a sound transmission hole in the noise eliminator illustrated in FIG. 1 .
- the configuration of the sound transmission hole formed in the inner pipe is differs from the noise eliminator 10 according to the first embodiment, and will be described in detail.
- the same reference numerals are applied to parts corresponding to the noise eliminator 10 of the first embodiment, and explanation of these parts will not be repeated.
- the sound transmission hole 18 b is oval-shaped as indicated by the solid line in FIG. 6 .
- This oval shape is an envelope configuration of a group of circles produced by sliding a circle indicated by the two-dot chain line in FIG. 6 in a given direction (indicated by the arrow G). That is, the configuration of the sound transmission hole 18 b is an oval shape having its longitudinal axis in a direction indicated by the arrow G.
- the distance from the center of the sound transmission hole 18 b indicated by the point E to the inner wall 19 b in the longitudinal axis direction (longitudinal direction of the sound transmission hole 18 ) indicated by the arrow G is set longer than the circle indicated by the two-dot chain line in FIG. 6 .
- the sound transmission hole inner wall 19 b cannot retain a water film in the longitudinal axis direction of the sound transmission hole 18 b . Even if a water film forms in this sound transmission hole 18 b , the film is easily broken in the longitudinal axis direction indicated by the arrow G. Consequently, in the noise eliminator 10 b of the present embodiment, even when water flowing in from the exhaust system upstream or water condensing in the interior of the noise eliminator attaches to the sound transmission hole, formation of a water film in the sound transmission hole can be suppressed.
- the longitudinal axis of the oval shape is set parallel to the axis center F of the inner pipe 14 . More specifically, the sound transmission hole 18 b is set so that the stream direction of exhaust gas passing through the interior of the inner pipe 14 corresponds with the direction in which the longitudinal axis of the sound transmission hole 18 b is set.
- the noise eliminator 10 b of the present embodiment a water film can be suppressed from forming in the sound transmission hole.
- the sound transmission hole in order to suppress a water film from forming in the sound transmission hole, was formed to have an oval shape having its longitudinal axis along the axis direction of the inner pipe 14 ; but the configuration of the sound transmission hole is not limited thereto.
- the inner wall 19 c of the sound transmission hole 18 c is formed with a saw tooth shape.
- saw tooth shape refers to a configuration different from the circular-shaped sound transmission hole, in which substantially triangle-shaped slits having the apex at a part 31 are successively formed. More specifically, in the sound transmission hole inner wall 19 c are alternately arranged a part 30 closer to the center axis of the sound transmission hole 18 c indicated by the point E and a part 31 at a longer distance from the center axis.
- the sound transmission hole inner wall 19 c When the configuration of the sound transmission hole 18 c is set in this manner, it is not possible for the sound transmission hole inner wall 19 c to retain a water film in the part 31 at a longer distance from the center E of the sound transmission hole 18 c . Thus, even if a water film forms in the sound transmission hole 18 c , the surface tension of the film is easily broken at the part 31 farther from the center E, thus enabling suppression of water film formation in the sound transmission hole.
- a groove 32 connecting adjoining sound transmission holes 18 d and 18 e there is formed a groove 32 connecting adjoining sound transmission holes 18 d and 18 e . Between the circular-shaped sound transmission holes 18 d and 18 e is arranged the linear groove 32 connecting these holes through the shortest distance. This groove 32 constitutes a communicating path which causes the sound transmission holes 18 d and 18 e to communicate with each other.
- the water constituting a water film in the one sound transmission hole 18 is pushed through the groove 32 to the other sound transmission hole 18 by effect of exhaust gas stream passing through the interior of the inner pipe 14 or of acceleration acting on the noise eliminator 10 b .
- the water constituting a water film formed in the sound transmission hole 18 d can pass, as indicated by the arrow H, through the groove 32 to the sound transmission hole 18 e . Accordingly, in the one sound transmission hole 18 d , the amount of water constituting a water film decreases and thus the water film tension becomes easily breakable.
- FIG. 9 illustrates an expanded sectional view of the portion of the inner-pipe peripheral wall A in FIG. 1 .
- the noise eliminator 10 c of the present embodiment differs from the noise eliminator 10 of the first embodiment in that a water repellent finish is applied to sound transmission holes, and will be described in detail below.
- the same reference numerals are applied to parts corresponding to the noise eliminator 10 of the first embodiment, and an explanation thereof will not be repeated.
- a water repellent layer 34 in the inner wall 19 d of a sound transmission hole 18 , as illustrated in FIG. 9 , there is formed a water repellent layer 34 .
- a water repellent film of fluorine resin or the like is formed in the inner wall 19 d .
- the water repellent layer 34 may be formed not only in the sound transmission hole inner wall 19 d but also in the entire inner pipe 14 d .
- the water repellent finish application process can be simplified.
- the inner wall 19 d of the sound transmission hole 18 cannot hold a water film. Accordingly, in the noise eliminator 10 c of the present embodiment, even when water flowing in from the exhaust system upstream or water condensing in the interior of the noise eliminator attaches to the sound transmission hole, formation of a water film in the sound transmission hole can be suppressed.
- FIG. 10 illustrates an expanded sectional view of the portion of the inner-pipe peripheral wall 13 A in FIG. 1 .
- the noise eliminator 10 d of the present embodiment differs from the noise eliminator 10 of the first embodiment in that a sound absorbing material is filled in the inner side of the inner wall of a sound transmission hole, and will be described in detail below.
- the same reference numerals are applied to parts corresponding to the noise eliminator 10 of the first embodiment, and their explanation will not be repeated.
- a sound absorbing material 16 b is, as illustrated in FIG. 10 , filled in the inner wall 19 d of a sound transmission hole 18 .
- a short projection 36 is integrally formed by press molding or the like.
- the projection 36 of the sound absorbing material 16 b fits into the inner side of the inner wall 19 of the sound transmission hole 18 formed in the inner pipe 14 e .
- the configuration of the projection 36 is set according to the configuration of the sound transmission hole 18 . In this manner, the sound absorbing material 16 b is filled in the inner side of the sound transmission hole 18 .
- the noise eliminator 10 d of the present embodiment when water flowing in from the exhaust system upstream, or water condensing in the interior of the noise eliminator 10 d attaches to the sound transmission hole 18 , it also naturally attaches to the projection 36 of the sound absorbing material 16 b , disposed in the inner side of the sound transmission hole 18 .
- the water attaching to the projection 36 disperses to parts other than the projection 36 of the sound absorbing material 16 b by the capillary phenomenon. Consequently, the projection 36 of the sound absorbing material 16 b does not continue to be all wet.
- the noise eliminator 10 of the present embodiment even when water flowing in from the exhaust system upstream or water condensing in the interior of the noise eliminator attaches to the sound transmission hole, formation of a water film in the sound transmission hole can be suppressed.
- FIG. 11 illustrates a cross section of an inner pipe
- FIG. 12 illustrates an expanded sectional view of the section of the inner-pipe peripheral wall I in FIG. 11
- FIG. 13 illustrates a view of the inner pipe having a cross section illustrated in FIG. 11 , as seen from the direction indicated by the arrow D
- FIG. 14 illustrates a cross section of an inner pipe in a noise eliminator according to a variation.
- the noise eliminator 10 d of the present embodiment differs from the noise eliminator 10 of the first embodiment in that the inner pipe is provided with a drift member drifting the exhaust gas stream, as will be described in detail below.
- the same reference numerals are applied to parts corresponding to the noise eliminator 10 of the first embodiment, and their explanation will not be repeated.
- the inner pipe 14 is provided with a drift member drifting the exhaust gas stream so that the exhaust gas stream does not impact directly against the sound transmission hole 18 .
- the drift member is arranged inside the inner pipe 14 ; because the exhaust gas stream containing moisture does not directly impact against the sound transmission hole 18 , fixing of the moisture contained in the exhaust gas stream to the sound transmission hole 18 is suppressed to a great extent.
- the drift member is arranged inside the inner pipe 14 to prevent the exhaust gas stream from impacting against the sound transmission hole 18 ; thus, formation of a water film in the sound transmission hole 18 can be suppressed.
- a louver 38 as illustrated in FIG. 11 is provided as the drift member in a protruding manner upstream of the sound transmission hole 18 in the inner-pipe inner wall 15 . More specifically, the louver 38 protrudes as illustrated in FIG. 12 , from the upstream end of the sound transmission hole 18 toward the inner pipe axis center F and at the same time in a manner inclined toward a downstream direction (direction indicated by the arrow D).
- the exhaust gas stream flowing along the inner-pipe inner wall 15 is polarized upstream of the sound transmission hole 18 toward the side having the inner pipe axis center F by the louver 38 . Consequently, the exhaust gas stream flowing inside the inner pipe 14 f does not directly impact against the sound transmission hole 18 in the downstream of the louver 38 , and thus little of the moisture contained in the exhaust gas attaches to the walls of the sound transmission hole 18 .
- the louver 38 is as illustrated in FIG. 13 , preferably arranged in a circular shape to cover the entire circumference of the inner-pipe inner wall 15 .
- the louver 38 having such a circular configuration not only polarizes the exhaust gas stream inside the inner pipe 14 f , but also functions as a “rib” reinforcing the inner pipe 14 f .
- the stiffness of the inner pipe 14 f can be improved.
- the thickness of the peripheral wall 13 of the inner pipe 14 f can be set thinner.
- the drift member drifting the exhaust gas stream to prevent the exhaust gas stream from impacting directly against the sound transmission hole 18 , the louver 38 protruding from the upstream end of the sound transmission hole 18 is provided, but the drift member is not limited to this configuration.
- the stream guide plate 40 may be a plate-shaped member arranged in the inner wall 15 of an upstream side end 41 of the inner pipe 14 g , the plate being disposed in a manner inclined relative to the stream direction (indicated by the arrow D) of exhaust gas flowing into the inner pipe 14 g . Then, the exhaust gas stream flowing into the upstream side end 41 of the inner pipe 14 g is as indicated by the arrow K in FIG. 14 , polarized by the stream guide plate 40 and guided to the area 39 (area surrounded by the dashed line in FIG. 14 ) where no sound transmission hole 18 is formed.
- the “area 39 where no sound transmission hole 18 is formed” refers to an area, downstream of the upstream end 41 of the inner pipe 14 g , and excluding the area 43 (indicated by the dotted line in FIG. 14 ) where the sound transmission hole 18 is formed.
- the stream guide plate 40 polarizes the exhaust gas stream flowing into the inner pipe 14 g so that the exhaust gas stream avoids this “area 43 where the sound transmission hole 18 is formed”.
- the louver 38 protruding from the upstream side of the sound transmission hole 18 is arranged inside the inner pipe 14 g , or the stream guide plate 40 is arranged in the upstream side end 41 , and thus very little moisture attaches to the sound transmission hole 18 . Consequently, formation of a water film in the sound transmission hole is suppressed.
- FIG. 15 schematically illustrates a cross section of the noise eliminator.
- the noise eliminator 10 f of the present embodiment differs from the noise eliminator 10 of the first embodiment in that a swirling stream (vortex) generation member is provided along the inner pipe inner wall for generating a swirling stream, and will be described in detail below.
- the same reference numerals are applied to parts corresponding to the noise eliminator 10 of the first embodiment, and their explanation will not be repeated.
- the swirling stream generation member 44 is, as illustrated in FIG. 15 , a plate-shaped member having a twisted configuration and arranged in the upstream end 41 inside the inner pipe 14 h .
- This twisted plate-shaped member generates a swirling stream swirling along the inner-pipe inner wall 15 .
- the exhaust gas stream flowing into the upstream end 41 of the inner pipe 14 h swirls around the inner pipe axis center F by the plate-shaped member.
- This swirling exhaust gas stream (swirling stream) flows, as indicated by the arrow L in FIG. 15 , in a downstream direction while swirling along the inner-pipe inner wall 15 .
- Acting on the exhaust gas swirling inside the inner pipe 14 h is a centrifugal force working toward the inner-pipe inner wall 15 around the axis center of the inner pipe 14 h.
- the noise eliminator 10 f of the present embodiment even if a water film forms in the sound transmission hole, the exhaust gas is pressed against the water film and thus the film tension is easily broken. Consequently, in the noise eliminator 10 of the present embodiment, formation of a water film in the sound transmission hole can be suppressed.
- the sound transmission hole 18 f is, as illustrated in FIG. 15 , formed to have a configuration along the flow of the generated swirling stream. More specifically, the sound transmission hole 18 is set so that the stream direction (indicated by the arrow L) of the swirling stream agrees with the longitudinal direction of the sound transmission hole 18 f.
- the sound transmission hole 18 f is configured in this manner, even if a water film forms in the sound transmission hole 18 f , the water film is polarized and deformed in the longitudinal direction of the sound transmission hole 18 f by the exhaust gas stream (swirling stream) flowing along the inner-pipe inner wall 15 , and, because the film includes thin patches, the film tension is easily broken.
- FIG. 16 schematically illustrates a cross section of the noise eliminator
- FIG. 17 illustrates an exemplary vortex generation member arranged in the noise eliminator
- FIG. 18 illustrates a cross section of an inner pipe in a noise eliminator according to a variation
- FIG. 19 illustrates a view of the inner pipe having a cross section illustrated in FIG. 18 , as seen from the direction indicated by the arrow D.
- the noise eliminator 10 g of the present embodiment differs from the noise eliminator 10 of the first embodiment in being provide with a vortex generation member generating a vortex along the inner-pipe inner wall, and will be described in detail below.
- the same reference numerals are applied to parts corresponding to the noise eliminator 10 of the first embodiment, and their explanation will not be repeated.
- the inner pipe 14 i is provided with a vortex generation member generating a vortex in the vicinity of the inner wall 15 of the inner pipe 14 i .
- the vortex generation member produces a vortex 48 upstream of the sound transmission hole 18 .
- the produced vortex 48 flows downstream along the inner wall of the inner pipe 14 towards the sound transmission hole 18 .
- the turbulent flow of the vortex 48 as it reaches the sound transmission hole 18 suppresses formation of water films in the sound transmission hole 18 , and, upon impact, acts to break up any films that may have formed.
- the noise eliminator 10 g of the present embodiment because the inner pipe 14 i is provided with the vortex generation member to produce a vortex in the vicinity of the inner-pipe inner wall 15 , formation of a water film in the sound transmission hole can be suppressed.
- a Karman vortex generation member 46 is, as illustrated in FIG. 16 , arranged in the upstream end 41 of the inner pipe 14 i .
- the Karman vortex generation member 46 can be, as illustrated in FIG. 17 , composed of a plate-shaped member having some thickness, for example.
- the member is disposed inside the inner pipe 14 i so that the axis center F of the inner pipe 14 i penetrates through the member.
- the exhaust gas stream flowing into the inner pipe 14 i from the direction indicated by the arrow D is divided into two streams (an upper stream and a lower stream indicated by the arrows M 1 and M 2 , respectively, in FIG. 16 ) by the Karman vortex generation member 46 .
- the two streams break away at a downstream end 46 e of the Karman vortex generation member 46 and alternately produce a vortex 48 .
- This Karman vortex 48 flows to the downstream side and reaches the sound transmission hole 18 .
- the turbulent flow of the vortex 48 suppresses formation of water films in the sound transmission hole 18 , and acts to break up any films that do form.
- the Karman vortex generation member 48 produces a vortex in the vicinity of the inner-pipe inner wall 15 , but the vortex generation member is not limited to this configuration.
- a protrusion 50 generating a vortex 51 in the vicinity of the inner-pipe inner wall 15 .
- a protrusion 50 may be, as illustrated in FIG. 18 , arranged for each sound transmission hole 18 in the upstream side of the hole.
- the protrusions 50 project, as illustrated in FIG. 19 , from the inner-pipe inner wall 15 toward the inner-pipe axis center F.
- the protrusion 50 is configured so that the flow along the inner wall 15 of the inner pipe 14 j can be separated away from the boundary layer as much as possible.
- FIG. 20 schematically illustrates a vertical section of the noise eliminator
- FIG. 21 illustrates a vertical section of an inner pipe in a noise eliminator according to a variation
- FIG. 22 illustrates a view of the inner pipe having a cross section illustrated in FIG. 21 , as seen from the direction indicated by the arrow D.
- the noise eliminator 10 of the present embodiment differs from the noise eliminator 10 of the first embodiment in that stream guide means are provided for directing a portion of the exhaust gas flowing into the inner pipe out from the upstream sound transmission hole to the sound absorbing chamber.
- stream guide means will be described in detail below, but the same reference numerals are applied to parts corresponding to the noise eliminator 10 of the first embodiment, and their explanation will not be repeated.
- the stream guide means cause a portion of the exhaust gas flowing inside the inner pipe 14 to flow out from inside the inner pipe 14 through the sound transmission hole 18 g in the upstream side to the sound absorbing chamber 17 . More specifically, in the sound transmission hole 18 g in the upstream side, the stream guide means produce an exhaust gas stream flowing from inside the inner pipe 14 to the sound absorbing chamber. 17 .
- the sound absorbing chamber 17 is a hermetically-closed space surrounded by the inner-pipe outer wall and outer-shell inner wall, with the exception of the sound transmission holes 18 g and 18 h , and the exhaust gas flowing out from the sound transmission hole 18 g in the upstream side to the sound absorbing chamber 17 flows back from the sound transmission hole 18 h in the downstream side into the inner pipe 14 . In the sound transmission hole 18 h in the downstream side, there is produced an exhaust gas stream flowing from the sound absorbing chamber 17 into the inner pipe 14 .
- an exhaust gas stream can be produced in such a manner that a portion of the streams flows out from inside the inner pipe 14 through the sound transmission hole 18 g in the upstream side to the sound absorbing chamber 17 and flows back through the sound transmission hole 18 h in the downstream side into the inner pipe 14 .
- the exhaust gas streams flows through both the upstream and downstream sound transmission holes 18 g and 18 h , formation of water films in the sound transmission holes 18 g and 18 h is suppressed, and any films that do form tend to be broken by the exhaust gas stream flowing through the sound transmission holes 18 g and 18 h . Accordingly, in the noise eliminator 10 h of the present embodiment, formation of a water film in the sound transmission hole can be further suppressed.
- a narrowed section 52 as illustrated in FIG. 20 is formed in the inner pipe 14 k as the stream guide means.
- the narrowed section 52 is a portion in which the cross sectional area (cross section orthogonal to the axis center F of the inner pipe 14 ) of the stream path formed inside the inner pipe 14 k is smaller than elsewhere, and disposed in the path of the inner pipe 14 k .
- the sound transmission holes 18 g and 18 h are formed upstream and downstream relative to this narrowed section 52 , respectively.
- the exhaust gas flowing out to the sound absorbing chamber 17 flows, as indicated by the arrow P in FIG. 20 , in a downstream direction inside the sound absorbing chamber 17 , and then flows through the downstream sound transmission hole 18 h into the downstream side relative to the narrowed section 52 in the inner pipe 14 k.
- the formation of the narrowed section 52 in the inner pipe 14 k allows a portion of the exhaust gas to flow out through the upstream sound transmission hole 18 g into the sound absorbing chamber 17 , but the stream guide means are not limited to this configuration.
- a duct 54 corresponding to the upstream sound transmission hole 18 g may be, as illustrated in FIG. 21 , arranged in the inner wall 15 of the inner pipe 141 in a manner corresponding to each of the upstream sound transmission holes 18 . Also, the duct 54 may protrude, as illustrated in FIG. 22 , from the inner wall 15 of the inner pipe 141 toward the axis center F of the inner pipe 141 , and have an opening facing the upstream side.
- the stream indicated by the arrow Q in FIG. 21 which flows along the inner-pipe inner wall 15 , flows from the opening of the duct 54 through the sound transmission hole 18 (in the upstream side) and flows out into the sound absorbing chamber 17 . Because the exhaust gas flowing out into the sound absorbing chamber 17 raises the pressure inside the sound absorbing chamber 17 , the exhaust gas flowing out into the sound absorbing chamber 17 flows back, as indicated by the arrow R in FIG. 21 , through the sound transmission hole 18 h in the downstream side into the inner pipe 141 .
- FIG. 23 schematically illustrates the noise eliminator and its peripheral device.
- the noise eliminator 10 i of the present embodiment is different from the noise eliminator 10 of the first embodiment in being provided with gas injection means for injecting gas into the sound absorbing chamber, and will be described in detail below.
- the same reference numerals are applied to parts corresponding to the noise eliminator 10 of the first embodiment, and their explanation will not be repeated.
- the gas injection means injects gas from the outside of the noise eliminator 10 i into the sound absorbing chamber 17 . Because the pressure of the injected gas is greater than the pressure inside the inner pipe 14 , when gas is injected into the sound absorbing chamber 17 , the gas inside the sound absorbing chamber 17 flows through the sound transmission hole 18 into the inner pipe 14 . In this way, a stream flowing from inside the sound absorbing chamber 17 through the sound transmission hole 18 and into the inner pipe 14 can be produced.
- a bypass stream path 60 which bypasses the fuel cell 82 and directly connects the oxidizing gas supplying path 87 and the interior of the sound absorbing chamber 17 as illustrated in FIG. 23 is provided as the gas injection means.
- One end of the bypass stream path 60 is connected to a gas outlet 57 arranged in the oxidizing gas supplying path 87 connecting a blower 86 and fuel cell body 82 a ; and the other end thereof is connected to a gas inlet 58 arranged in the outer shell 12 c .
- the blower 86 supplies, as indicated by the arrow S, oxidizing gas (air) through the oxidizing gas supplying path 87 to the fuel cell body 82 a , the oxidizing gas is simultaneously supplied to the bypass stream path 60 (indicated by the arrow T in FIG. 23 ).
- the oxidizing gas supplied to the bypass stream path 60 flows, as indicated by the arrow U, through the gas inlet 58 of the outer shell 12 into the sound absorbing chamber 17 .
- the oxidizing gas supplied to the fuel cell body 82 a is discharged as oxidizing gas from the fuel cell body 82 a , and subjected to flow rate adjustment by an adjustment valve 82 b , and flows, as indicated by the arrow D, into the inner pipe 14 of the noise eliminator 10 i.
- the pressure of oxidizing gas flowing in the bypass stream path 60 (the pressure of oxidizing gas injected into the sound absorbing chamber) is set higher than the pressure of exhaust gas flowing in the inner pipe 14 , so the oxidizing gas flowing through the gas inlet 58 into the sound absorbing chamber 17 flows from the sound absorbing chamber 17 through the sound transmission hole 18 into the inner pipe 14 .
- bypass stream path 60 directly connecting the oxidizing gas supplying path 87 outside the noise eliminator 10 and the interior of the sound absorbing chamber 17 is provided in the noise eliminator 10 of the present embodiment, such that a gas stream flowing from the sound absorbing chamber 17 through the sound transmission hole 18 into the inner pipe 14 can be formed. Accordingly, formation of a water film in the sound transmission hole can be further suppressed.
- oxidizing gas is removed from the oxidizing gas supplying path to the bypass stream path and injected into the sound absorbing chamber, but the configuration is not limited thereto.
- a gas outlet is arranged in an anode purge valve intermittently discharging anode gas (hydrogen) and is connected to the bypass stream path, whereby the anode gas is injected into the sound absorbing chamber.
- gas is intermittently supplied to the sound absorbing chamber and produces a pressure wave when injected, and any water films forming in the sound transmission hole 18 can be broken up by this pressure wave.
- a valve (not illustrated) which can be opened and closed instantaneously be provided in the bypass stream path 60 .
- the instantaneous opening or closing of this valve produces a pressure wave in the oxidizing gas downstream of the valve. When this pressure wave propagates through the sound absorbing chamber 17 to the sound transmission hole 18 .
- the adjustment valve 82 b is opened or closed instantaneously. Such instantaneous opening and closing of the adjustment valve 82 b produces a pressure wave as indicated by the arrow D in the exhaust gas flowing into the inner pipe 14 . This pressure wave propagates from the inner pipe 14 to the sound transmission hole 18 , and again acts to break up any water films forming in the sound transmission hole.
- FIG. 24 illustrates a vertical section of an inner pipe 14
- FIG. 25 illustrates a view of the inner pipe 14 having the cross section illustrated in FIG. 24 , as seen from the direction indicated by the arrow D.
- the noise eliminator 10 j of the present embodiment differs from the noise eliminator 10 of the first embodiment in that the sound transmission hole and the peripheral part thereof are formed projecting towards the axis center F of the inner pipe, as will be described in detail below.
- the same reference numerals are applied to parts corresponding to the noise eliminator 10 of the first embodiment, and their explanation will not be repeated.
- the sound transmission hole 18 i and its peripheral part 62 are, as illustrated in FIGS. 24 and 25 , arranged to project from the inner wall 15 of the inner pipe 14 m toward the inner-pipe axis center F.
- the exhaust gas (indicated by the arrow V) flowing along the inner wall 15 of the inner pipe 14 is polarized toward the inner-pipe axis center F by the peripheral part 62 of the sound transmission hole 18 i , such that a contracted flow area 64 (surrounded by the two-dot chain line in FIG. 24 ) having a relatively rapid flow is produced between the sound transmission hole 18 i and the inner-pipe axis center F. That is, the sound transmission hole 18 i is exposed to the rapidly flowing exhaust gas stream.
- the noise eliminator 10 i of the present embodiment even when a water film forms in the sound transmission hole 18 i , because the sound transmission hole 18 i is exposed to a relatively rapid flow, the water film is polarized towards a downstream direction and deformed, such that portions of the film are thinner and the film is, thus, easily broken or dispersed. Consequently, formation of water films in the sound transmission hole can be further suppressed.
- FIG. 26 schematically illustrates a vertical cross section of the noise eliminator
- FIG. 27 schematically illustrates a perspective view of an inner case constituting the noise eliminator.
- the noise eliminator 10 k of the present embodiment differs from the noise eliminator 10 of the first embodiment in including an outer shell allowing exhaust gas to flow therethrough and an inner case, having a plurality of through holes formed in a wall surface thereof, with a sound absorbing material filled in the interior thereof, the inner case being disposed over the entire cross section of the outer-shell stream path, and will be described in detail below.
- the inner case 66 is as illustrated in FIG. 27 , a hard case of a substantially rectangular shape having a plurality of through holes 18 j formed on the wall surface 68 thereof.
- the sound transmission hole 18 j is formed in the upstream wall surface 68 a and the downstream wall surface 68 b facing the wall surface 68 a ; gas can flow therethrough from the upstream side wall surface 68 a to the downstream side wall surface 68 b .
- the sound absorbing material 16 is filled in the inner side of the inner case wall surface 68 , i.e., inside the inner case 66 , which functions as a sound absorbing chamber 17 .
- the inner case 66 described above is, as illustrated in FIG. 26 , received and held in the inner side of the outer shell 12 d .
- a stream path 70 is formed in the inner side of the outer shell 12 d , and the inner case 66 is disposed so as to seal this stream path 70 .
- the wall surface 68 (the upstream side wall surface 68 a and the downstream side wall surface 68 b ) of the inner case 66 having the sound transmission hole 18 j is disposed over the entire cross section of the stream path 70 inside the outer shell 12 d.
- the noise eliminator 10 k When the noise eliminator 10 k is configured in this manner, all the exhaust gas flowing through the outer shell 12 d flows, as indicated by the arrow W, through the through hole 18 j of the inner-case wall surface 68 and the sound absorbing chamber 17 residing therein. Accordingly, in the noise eliminator 10 k of the present embodiment, formation of a water film in the through hole 18 j can be suppressed.
- the configuration of the inner case 66 and outer shell 12 d is set so that the area of the wall surface 68 having the through hole 18 j of the inner case 66 is maximized.
- the pressure loss caused by exhaust gas flowing through the inner case 66 can be reduced.
- FIG. 28 illustrates a vertical section of the noise eliminator
- FIG. 29 illustrates a view of a plate-shaped member constituting the noise eliminator, as seen from the direction indicated by the arrow D.
- the noise eliminator 10 m of the present embodiment is differs from the noise eliminator 10 of the first embodiment in that it includes a shell allowing exhaust gas to flow therethrough and a plate-shaped member having a plurality of through holes formed therein, the plate-shaped member partitioning the interior of the shell by a face thereof orthogonal to the direction of exhaust gas stream.
- the noise eliminator 10 m will be described in detail below.
- the plate-shaped member 72 is a hard plate member having a substantially circular shape as illustrated in FIG. 29 .
- a plurality of through holes 18 k are formed in a wall surface 73 thereof.
- a stream path 75 having a substantially circular-shaped cross section is, as illustrated in FIG. 28 , formed inside the shell 74 .
- a plurality of the plate-shaped members 72 are arranged inside the shell 74 so as to divide the stream path 75 inside the shell 74 by a face thereof orthogonal to the stream direction (direction indicated by the arrow D) of exhaust gas. That is, the through hole 18 k of the plate-shaped member 72 has the same through direction as the direction of exhaust gas stream.
- the exhaust gas flowing in from the direction indicated by the arrow D flows, as indicated by the arrow D, through the through hole 18 k of the plate-shaped member 72 .
- the exhaust gas stream indicated by the arrow D is a turbulent flow produced upstream in the exhaust system, and this turbulent flow is rectified when the exhaust gas flows through the plurality of through holes 18 k formed in the plate-shaped member 72 .
- the turbulent flow is rectified each time it passes through the through holes 18 k of each plate-shaped member, whereby the sound propagating from the exhaust system upstream to the interior of the shell 74 is silenced.
- the flowing—in exhaust gas is reliably directed through the through hole 18 k of the plate-shaped member 72 , and formation of water films in the through hole 18 k is thereby suppressed.
- a desired noise elimination performance can be achieved without using a sound absorbing material.
- the noise eliminator for a fuel cell according to the present invention is useful as a noise eliminator in an exhaust system of a fuel cell.
Abstract
A noise eliminator for a fuel cell installed in an exhaust system discharging exhaust gas from the fuel cell, comprising an inner pipe having a plurality of sound transmission holes formed in its peripheral wall and allowing the exhaust gases to flow therethrough and an outer shell disposed to surround the inner pipe through a prescribed distance from the peripheral wall and constituting a sound absorbing chamber with a sound absorbing material filled in the clearance thereof from the inner pipe. The sound transmission hole has an inner diameter of 3 mm or greater, and a depth of 1.2 mm or less.
Description
- The present invention relates to a structure providing countermeasures against condensation of moisture in exhaust gas with respect to a noise eliminator installed in an exhaust system of fuel cell.
- In fuel cells, a power generating reaction between fuel gas supplied to the anode electrode and oxidizing gas supplied to the cathode electrode occurs in an electrolyte, in conjunction with moisture is produced. The produced moisture is discharged as fuel cell exhaust gas, along with unused fuel gas and oxidizing gas, through an exhaust system connected to the fuel cell. In such an exhaust system, the gas stream may produce a sound of a relatively high frequency, on the order of 500 Hz to 2000 Hz. In order to reduce the noise produced by the gas stream, the exhaust system of a fuel cell vehicle or the like is typically equipped with a sound absorption type noise eliminator whose interior is packed with a sound absorbing material (noise elimination material) such as glass wool.
- One example of a noise eliminator of this type is that having the cross-sectional structure illustrated in
FIG. 31 . Thisnoise eliminator 100 includes aninner pipe 102 through which the exhaust gas from the fuel cell flows, and anouter shell 104 surrounding theinner pipe 102. Asound absorbing material 106 such as glass wool is filled between theinner pipe 102 andouter shell 104. A plurality ofsound transmission holes 108 are formed in the peripheral wall of theinner pipe 102. The sound radiated from thesound transmission holes 108 toward thesound absorbing material 106 is attenuated while subjected to repeated scattering and interference in thesound absorbing material 106, and is consequently absorbed by thesound absorbing material 106. - Meanwhile, fuel cell exhaust gases contain a large amount of moisture produced by the reaction of hydrogen and oxygen. This moisture may condense in the exhaust system upstream to form liquid water which flows into the noise eliminator, or the moisture may condense in the interior of the noise eliminator. As a result, water may accumulate in the vertical lower part (hereinafter referred to as the bottom part) of the noise eliminator. When this happens, because the sound absorbing material filled in the bottom part of the noise eliminator absorbs and holds the water (“contains water”), a specified sound absorption performance cannot be achieved, and, thus, noise elimination performance is impaired.
- Means of addressing this problem have been proposed in the conventional art, such as, for example, the
noise eliminator 120 proposed in Japanese Patent Laid-Open Publication No. 2002-206413. As illustrated inFIG. 32 of that publication, in thenoise eliminator 120, the interior of thenoise eliminator 120 is vertically partitioned into upper and lower parts by apartition board 124 having acontinuous hole 123, whereby asound absorbing chamber 126 andexpansion chamber 128 are formed. Aninner pipe 130 havingsound transmission holes 136 is arranged inside thesound absorbing chamber 126, and a sound absorbing material is filled to surround theinner pipe 130. With this structure, even when thesound absorbing material 126 in the vertical lower side of theinner pipe 130 contains water, it is possible to cause the water to drip through thecontinuous hole 123 of apartition board 124 into theexpansion chamber 128. The water falling into theexpansion chamber 128 is successively discharged through thesound transmission holes 136 of a guidingpipe 134 to the outside of thenoise eliminator 120. - However, in the noise eliminator of Japanese Patent Laid-Open Publication No. 2002-206413, the water flowing from the exhaust system upstream into the noise eliminator or the water, contained in exhaust gas, and condensing in the interior of the noise eliminator can cause a water film to be produced in the inner pipe or sound transmission holes. When a water film is produced in the sound transmission holes, much of the sound energy in the inner pipe or the guiding pipe is not discharged through the sound transmission holes to the sound absorbing chamber and expansion chamber, impairing the noise elimination performance of the noise eliminator. Thus, there has been a need for a tangible approach for suppressing formation of a water film in the sound transmission holes.
- The present invention provides a noise eliminator allowing suppression of formation of a water film in sound transmission holes. A noise eliminator for a fuel cell according to the present invention includes an inner pipe having a plurality of sound transmission holes formed in a peripheral wall thereof and allowing exhaust gas to flow therethrough, and an outer shell, arranged to surround the inner pipe through a prescribed distance from the peripheral wall, and constituting a sound absorbing chamber with a sound absorbing material filled in a space between the outer shell and the inner pipe. The shape of the sound transmission holes is configured so that no liquid film is formed in the holes. Also, the shape of the sound transmission hole can be construed to have a function of reducing liquid surface tension in the hole.
- The noise eliminator for a fuel cell according to the present invention has the following configurations.
- (1) In one configuration, a noise eliminator for a fuel cell according to the present invention is characterized by including an inner pipe having a plurality of sound transmission holes formed in a peripheral wall thereof and allowing exhaust gas to flow therethrough, and an outer shell, arranged to surround the inner pipe through a prescribed distance from the peripheral wall, and constituting a sound absorbing chamber with a sound absorbing material filled in a space between the outer shell and the inner pipe, wherein the sound transmission hole has an inner diameter of 3 mm or longer and a depth of 1.2 mm or shorter.
- Here, the peripheral part of the sound transmission hole in the inner pipe is preferably formed thinner in wall thickness than the other part thereof.
- Also, a rib reinforcing the inner pipe is preferably formed between the sound transmission holes.
- (2) In another configuration, a noise eliminator for a fuel cell according to the present invention is characterized by including an inner pipe having a plurality of sound transmission holes formed in a peripheral wall thereof and allowing exhaust gas to flow therethrough, and an outer shell, arranged to surround the inner pipe through a prescribed distance from the peripheral wall, and constituting a sound absorbing chamber with a sound absorbing material filled in a space between the outer shell and the inner pipe, wherein the sound transmission hole is formed in the shape of an oval having a longitudinal axis along the axis direction of the inner pipe.
- (3) In another configuration, a noise eliminator for a fuel cell according to the present invention is characterized by including an inner pipe having a plurality of sound transmission holes formed in a peripheral wall thereof and allowing exhaust gas to flow therethrough, and an outer shell, arranged to surround the inner pipe through a prescribed distance from the peripheral wall, and constituting a sound absorbing chamber with a sound absorbing material filled in a space between the outer shell and the inner pipe, wherein there is formed a groove connecting the adjoining sound transmission holes.
- (4) In still another configuration, a noise eliminator for a fuel cell according to the present invention is characterized by including an inner pipe having a plurality of sound transmission holes formed in a peripheral wall thereof and allowing exhaust gas to flow therethrough, and an outer shell, arranged to surround the inner pipe through a prescribed distance from the peripheral wall, and constituting a sound absorbing chamber with a sound absorbing material filled in a space between the outer shell and the inner pipe, wherein the inner wall of the sound transmission hole is formed with a saw-tooth shape.
- (5) In yet another configuration, a noise eliminator for a fuel cell according to the present invention is characterized by including an inner pipe having a plurality of sound transmission holes formed in a peripheral wall thereof and allowing exhaust gas to flow therethrough, and an outer shell, arranged to surround the inner pipe through a prescribed distance from the peripheral wall, and constituting a sound absorbing chamber with a sound absorbing material filled in a space between the outer shell and the inner pipe, wherein a water repellant layer is formed in the inner wall of the sound transmission hole.
- (6) In another configuration, a noise eliminator for a fuel cell according to the present invention is characterized by including an inner pipe having a plurality of sound transmission holes formed in a peripheral wall thereof and allowing exhaust gas to flow therethrough, and an outer shell, arranged to surround the inner pipe through a prescribed distance from the peripheral wall, and constituting a sound absorbing chamber with a sound absorbing material filled in a space between the outer shell and the inner pipe, wherein a sound absorbing material is filled in the inner side of the inner wall of the sound transmission hole.
- (7) In another configuration, a noise eliminator for a fuel cell according to the present invention is characterized by including an inner pipe having a plurality of sound transmission holes formed in a peripheral wall thereof and allowing exhaust gas to flow therethrough, and an outer shell, arranged to surround the inner pipe through a prescribed distance from the peripheral wall, and constituting a sound absorbing chamber with a sound absorbing material filled in a space between the outer shell and the inner pipe, wherein the inner pipe is provided with a drift member drifting an exhaust gas stream so that the exhaust gas stream is prevented from directly impacting the sound transmission hole.
- Here, the drift member is preferably a louver protruding in a manner inclined from an upstream end of the sound transmission hole to a downstream direction in the inner-pipe inner wall.
- Also, the drift member may be arranged in the inner wall of an upstream portion of the inner pipe, being preferably a stream guide plate which guides exhaust gas to an area where no sound transmission hole is formed.
- (8) In another configuration, a noise eliminator for a fuel cell according to the present invention is characterized by including a swirling stream generation member for generating a swirling stream along the inner pipe inner wall, the member being disposed upstream in the inner pipe.
- (9) In another configuration, a noise eliminator for a fuel cell according to the present invention is characterized by including an inner pipe having a plurality of sound transmission holes formed in a peripheral wall thereof and allowing exhaust gas to flow therethrough, and an outer shell, arranged to surround the inner pipe through a prescribed distance from the peripheral wall, and constituting a sound absorbing chamber with a sound absorbing material filled in a space between the outer shell and the inner pipe, wherein a vortex generation member generating a vortex in the vicinity of the inner-pipe inner wall is arranged in the inner pipe.
- (10) In another configuration, a noise eliminator for a fuel cell according to the present invention is characterized by including stream guide means for causing a part of exhaust gas flowing into the inner pipe to flow out from inside the inner pipe through the upstream-side sound transmission holes to the sound absorbing chamber, wherein the exhaust gas flowing out to the sound absorbing chamber flows through the downstream-side sound transmission holes back into the inner pipe.
- Here, the stream guide means may be a narrowed portion formed in the path of the inner pipe, or the stream guide means may be a duct arranged in the inner-pipe inner wall in a manner corresponding to the upstream-side sound transmission hole.
- (11) In another configuration, a noise eliminator for a fuel cell according to the present invention is characterized by including an inner pipe having a plurality of sound transmission holes formed in a peripheral wall thereof and allowing exhaust gas to flow therethrough, and an outer shell, arranged to surround the inner pipe through a prescribed distance from the peripheral wall, and constituting a sound absorbing chamber with a sound absorbing material filled in a space between the outer shell and the inner pipe, the noise eliminator further including gas injection means for injecting gas from outside the noise eliminator directly to the sound absorbing chamber so that gas flows from the sound absorbing chamber through the sound transmission holes into the inner pipe.
- (12) In another configuration, a noise eliminator for a fuel cell according to the present invention is characterized by including an inner pipe having a plurality of sound transmission holes formed in a peripheral wall thereof and allowing exhaust gas to flow therethrough, and an outer shell, arranged to surround the inner pipe through a prescribed distance from the peripheral wall, and constituting a sound absorbing chamber with a sound absorbing material filled in a space between the outer shell and the inner pipe, wherein the sound transmission hole and a peripheral part thereof are formed in a manner projecting toward the axis center of the inner pipe.
- (13) In another configuration, a noise eliminator for a fuel cell according to the present invention is characterized by including an outer shell allowing exhaust gas to flow therethrough, and an inner case having a plurality of through holes formed in a peripheral wall thereof and constituting a sound absorbing chamber with a sound absorbing material filled in the interior thereof, wherein the inner case is arranged over the entire stream path cross section of the outer shell so that all the exhaust gas flowing through the outer shell flows through the interior of the inner case.
- (14) In another configuration, a noise eliminator for a fuel cell according to the present invention is characterized by including a shell allowing exhaust gas to flow therethrough, and a plate-shaped member partitioning the interior of the shell by a face thereof orthogonal to the direction of exhaust gas stream and having a plurality of through holes formed therein.
-
FIG. 1 is a vertical section of a noise eliminator according to a first embodiment of the present invention; -
FIG. 2 is an expanded sectional view of an inner-pipe peripheral wall in the noise eliminator according to the first embodiment of the present invention, being an expanded sectional view of the portion A inFIG. 1 ; -
FIG. 3 is an expanded sectional view of an inner-pipe peripheral wall in a noise eliminator according to a variation of the first embodiment of the present invention, being an expanded sectional view of the portion A ofFIG. 1 ; -
FIG. 4 is a vertical section of a noise eliminator according to another variation of the first embodiment of the present invention; -
FIG. 5 is a view of an inner pipe having a cross section illustrated inFIG. 4 , as seen from the direction indicated by the arrow D; -
FIG. 6 is a view illustrating a configuration of a sound transmission hole in a noise eliminator according to a second embodiment of the present invention; -
FIG. 7 is a view illustrating a configuration of a sound transmission hole in a noise eliminator according to a variation of the second embodiment of the present invention; -
FIG. 8 is a view illustrating a configuration of a sound transmission hole in a noise eliminator according to another variation of the second embodiment of the present invention; -
FIG. 9 is an expanded sectional view of an inner-pipe peripheral wall in a noise eliminator according to a third embodiment of the present invention, being an expanded sectional view of the portion A inFIG. 1 ; -
FIG. 10 is an expanded sectional view of an inner-pipe peripheral wall in a noise eliminator according to a fourth embodiment of the present invention, being an expanded sectional view of the portion A inFIG. 1 ; -
FIG. 11 is a vertical section of an inner pipe in a noise eliminator according to a fifth embodiment of the present invention; -
FIG. 12 is an expanded sectional view of the inner-pipe peripheral wall portion I inFIG. 11 ; -
FIG. 13 is a view of the inner pipe having a cross section illustrated inFIG. 11 , as seen from the direction indicated by the arrow D; -
FIG. 14 is a vertical section of an inner pipe in a noise eliminator according to a variation of the fifth embodiment of the present invention; -
FIG. 15 is a view schematically illustrating a vertical cross section of a noise eliminator according to a sixth embodiment of the present invention; -
FIG. 16 is a view schematically illustrating a vertical cross section of a noise eliminator according to a seventh embodiment of the present invention; -
FIG. 17 is a view illustrating an exemplary vortex generation member arranged in the noise eliminator according to the seventh embodiment of the present invention; -
FIG. 18 is a vertical section of an inner pipe in a noise eliminator according to a variation of the seventh embodiment of the present invention; -
FIG. 19 is a view of the inner pipe having a cross section illustrated inFIG. 18 , as seen from the direction indicated by the arrow D; -
FIG. 20 is a view schematically illustrating a vertical cross section of a noise eliminator according to an eighth embodiment of the present invention; -
FIG. 21 is a vertical section of an inner pipe in a noise eliminator according to a variation of the eighth embodiment of the present invention; -
FIG. 22 is a view of the inner pipe having a cross section illustrated inFIG. 21 , as seen from the direction indicated by the arrow D; -
FIG. 23 is a view schematically illustrating a noise eliminator according to a ninth embodiment of the present invention, and a peripheral device; -
FIG. 24 is a vertical section of a noise eliminator according to a tenth embodiment of the present invention; -
FIG. 25 is a view of the inner pipe having a cross section illustrated inFIG. 24 , as seen from the direction indicated by the arrow D; -
FIG. 26 is a view schematically illustrating a vertical cross section of a noise eliminator according to an eleventh embodiment of the present invention; -
FIG. 27 is a perspective view of an inner case in a noise eliminator according to the eleventh embodiment of the present invention; -
FIG. 28 is a vertical section of a noise eliminator according to a twelfth embodiment of the present invention; -
FIG. 29 is a view of a plate-shaped member in the noise eliminator according to the twelfth embodiment of the present invention, as seen from a direction indicated by the arrow D ofFIG. 28 ; -
FIG. 30 is a view illustrating an exemplary schematic configuration of a fuel cell system; -
FIG. 31 is a transverse sectional view of a sound absorption type noise eliminator; and -
FIG. 32 is a vertical section of a noise eliminator described in Japanese Patent Laid-Open Publication No. 2002-206413. - Embodiments of the present invention will be described in detail below with reference to the drawings.
- An exhaust system of a fuel cell system in which a
noise eliminator 10 of the present embodiment is used will be schematically described with reference toFIG. 30 . Thefuel cell system 80 includes afuel cell 82, ahydrogen tank 84 supplying hydrogen gas to thefuel cell 82, ablower 86 supplying oxidizing gas to thefuel cell 82, and an exhaust system 88 (indicated by the two-dot chain line inFIG. 30 ) discharging exhaust gas from thefuel cell 82. - The
hydrogen tank 84 is joined through a fuelgas supplying path 85 to thefuel cell 82, and hydrogen gas (fuel gas) stored in thehydrogen tank 84 is supplied, after being subjected to flow rate adjustment by aregulator 90, through acontrol valve 92 to thefuel cell 82. Theblower 86 is connected through an oxidizinggas supplying path 87 to thefuel cell 82, whereby oxidizing gas (air) is supplied to thefuel cell 82. In thefuel cell 82, the supplied hydrogen gas and air react to produce electric energy and at the same time produce moisture. - Air unused in the reaction and oxidizing gas containing moisture (water vapor) produced in the fuel cell are discharged from the
fuel cell 82 through a given exhaust system. Thenoise eliminator 10 is disposed at the tail end of this exhaust system; the exhaust gas containing moisture, and water being the result of moisture contained in exhaust gas condensing in the interior of the preceding exhaust system relative to thenoise eliminator 10 flow from the upstream end of the exhaust system upstream (the end indicated by the arrow D ofFIG. 1 ) into thenoise eliminator 10. - The noise eliminator according to the present embodiment is arranged in the exhaust system of the above described fuel cell system. More specifically, the noise eliminator is installed as an exhaust sound noise elimination device (muffler) for a fuel cell vehicle in the underbody (not illustrated) towards the rear of the vehicle hung by a bracket or the like.
- The
noise eliminator 10 according to the present embodiment will be described with reference toFIGS. 1 to 4 .FIG. 1 illustrates a vertical section configuration of the noise eliminator;FIG. 2 illustrates an expanded sectional view of the section of the inner-pipe peripheral wall A inFIG. 1 ;FIG. 3 illustrates an expanded sectional view of another example inner-pipe peripheral wall;FIG. 4 illustrates a vertical section configuration of a another example noise eliminator; andFIG. 5 illustrates a view of an inner pipe having a cross section illustrated inFIG. 4 , as seen from the direction indicated by the arrow D. - The
noise eliminator 10 includes, as illustrated inFIG. 1 , anouter shell 12 constituting the outer covering of the noise eliminator and aninner pipe 14, arranged within theouter shell 12, and allowing exhaust gas to flow therethrough. Asound absorbing material 16 is filled between theinner pipe 14 andouter shell 12, to thereby form asound absorbing chamber 17. As indicated by the arrow D, the exhaust gas flowing from the exhaust system upstream side into the noise eliminator passes through theinner pipe 14 and is discharged to the outside of thenoise eliminator 10. The sound transmitted along with the exhaust gas from the exhaust system upstream side into theinner pipe 14 is radiated from sound transmission holes 18 arranged in aperipheral wall 13 of theinner pipe 14 toward thesound absorbing material 16, and absorbed by thesound absorbing material 16. In this way, thenoise eliminator 10 achieves a given noise elimination performance. - The
inner pipe 14 is, as illustrated inFIG. 2 , constituted of anouter pipe section 20 having a plurality of sound transmission holes 18 formed in aperipheral wall 13 thereof, and aninner pipe section 22, installed in the inner side of theperipheral wall 13 of theouter pipe section 20, and reinforcing theouter pipe section 20. Theouter pipe section 20 is made of synthetic resin, the wall thickness (indicated by the size B inFIG. 2 ) thereof being 1.2 mm or smaller. In theouter pipe section 20, there are formed many sound transmission holes 18, the inner diameter of the sound transmission hole 18 (indicated by the size C inFIG. 2 ) being set to 3 mm or larger. - Meanwhile, the wall thickness of the
inner pipe section 22 is formed larger than theouter pipe section 20. In theinner pipe section 22, there are formed a plurality of throughholes 23 in a manner corresponding to that used to form the above described sound transmission holes 18. The configuration of the through hole is designed so as not to seal thesound transmission hole 18 formed in theouter pipe section 20 when theinner pipe section 22 is installed in theouter pipe section 20. When theinner pipe section 22 having a relatively large wall thickness is inserted and welded to theouter pipe section 20, the thin-walledouter pipe section 20 is reinforced. - With the above arrangement, the
inner pipe 14 can be made of synthetic resin and have a desired stiffness, and sound transmission holes 18 having an inner diameter of 3 mm or greater and a depth of 1.2 mm or less can be formed in the peripheral wall of theinner pipe 14. The word “depth” used herein refers to the length of thesound transmission hole 18 in the direction along the center axis of thesound transmission hole 18 indicated by the dashed line E inFIG. 2 , and the wall thickness of the part (theouter pipe section 20 in the present embodiment) in which the sound transmission holes are formed. - While the inner diameter of the
sound transmission hole 18 is 3 mm or larger, the depth thereof is set to a sufficiently small value of 1.2 mm or less. While there is formed a water film having a size corresponding to the inner diameter of thesound transmission hole 18, because the area of the inner wall of thesound transmission hole 18 holding the water film is small, it is not possible for the inner wall of thesound transmission hole 18 to retain the water film. Consequently, in thenoise eliminator 10 of the present embodiment, even when water flowing in from the exhaust system upstream side or water condensing in the interior of the noise eliminator attaches to the sound transmission holes, formation of a water film in the sound transmission holes can be suppressed. - In the
noise eliminator 10 according to the present embodiment, in order to implement the inner pipe of synthetic resin having the sound transmission holes 18 of an inner diameter of 3 mm or larger and a depth of 1.2 mm or smaller, theinner pipe section 22 reinforcing theouter pipe section 20 was inserted to the interior of the thin-walledouter pipe section 20 in which the sound transmission holes 18 are formed, but the structure of the inner pipe is not limited thereto. The inner pipe can also be implemented by various embodiments described below. - For example, as with the variation illustrated in
FIG. 3 , it is also preferable that the wall of theperipheral part 24 of thesound transmission hole 18 in theinner pipe 14 b is formed smaller than theother part 25. Here, theperipheral part 24 is a part adjoining to the inner wall of thesound transmission hole 18 in which the thickness closer to the inner wall of thesound transmission hole 18 is less than elsewhere. In the inner wall of thesound transmission hole 18, the wall thickness (indicated by the size B) is 1.2 mm or less. Theperipheral part 24 can be formed by cutting or injection molding. - Meanwhile, “the other part” (indicated by
reference numeral 25 inFIG. 3 ) which is at a longer distance from thesound transmission hole 18 than theperipheral part 24, has a sufficiently larger wall thickness than the part in which thesound transmission hole 18 is formed. - In this way, when the
peripheral part 24 of thesound transmission hole 18 is formed thinner than theother part 25, it is possible to provide in the inner pipe of synthetic resin a sound transmission hole which ensures the stiffness of the inner pipe and which has the dimensions described above which suppress formation of a water film. - Also, as with the variation illustrated in
FIGS. 4 and 5 , it is also preferable that arib 28 reinforcing theinner pipe 14 c is formed between the sound transmission holes 18. In theinner pipe 14 c, there is formed arib 28 protruding from theinner wall 15 toward the axis center (indicated by F inFIG. 4 ) of theinner pipe 14 c. Thisrib 28 is formed integrally with theinner pipe 14 c; in the inner wall of theinner pipe 14 c are formed an axis-direction rib 28 a extending in a direction along the axis center of theinner pipe 14 c and a circular shapedrib 28 b extending in a circular shape in a direction orthogonal to the axis center of theinner pipe 14 c. Theseribs 28 are formed between the sound transmission holes 18 so as to avoid interfering with the sound transmission holes formed in theinner pipe 14 c. - Meanwhile, except the part in which the
rib 28 is formed, theinner pipe 14 c is formed thinner to have a wall thickness of 1.2 mm or less; thesound transmission hole 18 is formed in this part. - In this way, when the
rib 28 is formed in theinner wall 15 of the thin-walled inner pipe, it is possible to provide in theinner pipe 14 c of synthetic resin thesound transmission hole 18 of dimensions which suppress formation of a water film, while ensuring the stiffness of theinner pipe 14. - A noise eliminator 10 b according to the present embodiment will be described with reference to
FIG. 6 .FIG. 6 illustrates a configuration of a sound transmission hole in the noise eliminator illustrated inFIG. 1 .FIG. 7 and illustrate alternative configurations of a sound transmission hole according to the present invention. In the noise eliminator 10 b of the present embodiment, the configuration of the sound transmission hole formed in the inner pipe is differs from thenoise eliminator 10 according to the first embodiment, and will be described in detail. The same reference numerals are applied to parts corresponding to thenoise eliminator 10 of the first embodiment, and explanation of these parts will not be repeated. - According to the present embodiment, the
sound transmission hole 18 b is oval-shaped as indicated by the solid line inFIG. 6 . This oval shape is an envelope configuration of a group of circles produced by sliding a circle indicated by the two-dot chain line inFIG. 6 in a given direction (indicated by the arrow G). That is, the configuration of thesound transmission hole 18 b is an oval shape having its longitudinal axis in a direction indicated by the arrow G. The distance from the center of thesound transmission hole 18 b indicated by the point E to theinner wall 19 b in the longitudinal axis direction (longitudinal direction of the sound transmission hole 18) indicated by the arrow G is set longer than the circle indicated by the two-dot chain line inFIG. 6 . - When the configuration of the
sound transmission hole 18 b is set in this manner, the sound transmission holeinner wall 19 b cannot retain a water film in the longitudinal axis direction of thesound transmission hole 18 b. Even if a water film forms in thissound transmission hole 18 b, the film is easily broken in the longitudinal axis direction indicated by the arrow G. Consequently, in the noise eliminator 10 b of the present embodiment, even when water flowing in from the exhaust system upstream or water condensing in the interior of the noise eliminator attaches to the sound transmission hole, formation of a water film in the sound transmission hole can be suppressed. - Also, in the
sound transmission hole 18 b, the longitudinal axis of the oval shape is set parallel to the axis center F of theinner pipe 14. More specifically, thesound transmission hole 18 b is set so that the stream direction of exhaust gas passing through the interior of theinner pipe 14 corresponds with the direction in which the longitudinal axis of thesound transmission hole 18 b is set. - Accordingly, even if a water film forms in the
sound transmission hole 18 b, the water film is unevenly distributed and deformed in the longitudinal axis direction by the exhaust gas stream passing through theinner pipe 14. Because thin portions of the water film are thus formed, the film tension is easily broken. Consequently, in the noise eliminator 10 b of the present embodiment, a water film can be suppressed from forming in the sound transmission hole. - In the noise eliminator 10 b of the present embodiment, in order to suppress a water film from forming in the sound transmission hole, the sound transmission hole was formed to have an oval shape having its longitudinal axis along the axis direction of the
inner pipe 14; but the configuration of the sound transmission hole is not limited thereto. - For example, as with the variation illustrated in
FIG. 7 , it is also preferable that theinner wall 19 c of thesound transmission hole 18 c is formed with a saw tooth shape. The expression “saw tooth shape” used herein refers to a configuration different from the circular-shaped sound transmission hole, in which substantially triangle-shaped slits having the apex at apart 31 are successively formed. More specifically, in the sound transmission holeinner wall 19 c are alternately arranged apart 30 closer to the center axis of thesound transmission hole 18 c indicated by the point E and apart 31 at a longer distance from the center axis. - When the configuration of the
sound transmission hole 18 c is set in this manner, it is not possible for the sound transmission holeinner wall 19 c to retain a water film in thepart 31 at a longer distance from the center E of thesound transmission hole 18 c. Thus, even if a water film forms in thesound transmission hole 18 c, the surface tension of the film is easily broken at thepart 31 farther from the center E, thus enabling suppression of water film formation in the sound transmission hole. - Also, as with the variation illustrated in
FIG. 8 , it is also preferable that there is formed agroove 32 connecting adjoining sound transmission holes 18 d and 18 e. Between the circular-shaped sound transmission holes 18 d and 18 e is arranged thelinear groove 32 connecting these holes through the shortest distance. Thisgroove 32 constitutes a communicating path which causes the sound transmission holes 18 d and 18 e to communicate with each other. - When such a
groove 32 is provided, even if a water film forms in these sound transmission holes 18, the water constituting a water film in the onesound transmission hole 18 is pushed through thegroove 32 to the othersound transmission hole 18 by effect of exhaust gas stream passing through the interior of theinner pipe 14 or of acceleration acting on the noise eliminator 10 b. For example, the water constituting a water film formed in thesound transmission hole 18 d can pass, as indicated by the arrow H, through thegroove 32 to thesound transmission hole 18 e. Accordingly, in the onesound transmission hole 18 d, the amount of water constituting a water film decreases and thus the water film tension becomes easily breakable. - Consequently, according to the noise eliminator of the present embodiment, each time the sound transmission holes 18 d and 18 e is subjected to effects of exhaust gas stream inside the
inner pipe 14 or of acceleration, the number of sound transmission holes in which a water film forms can be reduced, thus allowing suppression of water film formation in the sound transmission holes. - A noise eliminator 10 c according to the present embodiment will be described with reference to
FIG. 9 .FIG. 9 illustrates an expanded sectional view of the portion of the inner-pipe peripheral wall A inFIG. 1 . The noise eliminator 10 c of the present embodiment differs from thenoise eliminator 10 of the first embodiment in that a water repellent finish is applied to sound transmission holes, and will be described in detail below. The same reference numerals are applied to parts corresponding to thenoise eliminator 10 of the first embodiment, and an explanation thereof will not be repeated. - According to the present embodiment, in the
inner wall 19 d of asound transmission hole 18, as illustrated inFIG. 9 , there is formed awater repellent layer 34. In thiswater repellent layer 34, a water repellent film of fluorine resin or the like is formed in theinner wall 19 d. In this case, thewater repellent layer 34 may be formed not only in the sound transmission holeinner wall 19 d but also in the entireinner pipe 14 d. When a water repellent finish is applied to the entireinner pipe 14 d, the water repellent finish application process can be simplified. - When the above described water repellent finish is applied and the
water repellent layer 34 is formed at least in theinner wall 19 d of thesound transmission hole 18, theinner wall 19 d of thesound transmission hole 18 cannot hold a water film. Accordingly, in the noise eliminator 10 c of the present embodiment, even when water flowing in from the exhaust system upstream or water condensing in the interior of the noise eliminator attaches to the sound transmission hole, formation of a water film in the sound transmission hole can be suppressed. - A noise eliminator 10 d according to the present embodiment will be described with reference to
FIG. 10 .FIG. 10 illustrates an expanded sectional view of the portion of the inner-pipe peripheral wall 13 A inFIG. 1 . The noise eliminator 10 d of the present embodiment differs from thenoise eliminator 10 of the first embodiment in that a sound absorbing material is filled in the inner side of the inner wall of a sound transmission hole, and will be described in detail below. The same reference numerals are applied to parts corresponding to thenoise eliminator 10 of the first embodiment, and their explanation will not be repeated. - According to the present embodiment, a
sound absorbing material 16 b is, as illustrated inFIG. 10 , filled in theinner wall 19 d of asound transmission hole 18. In thesound absorbing material 16 b, ashort projection 36 is integrally formed by press molding or the like. When thesound absorbing material 16 b is placed around theinner pipe 14 e, theprojection 36 of thesound absorbing material 16 b fits into the inner side of theinner wall 19 of thesound transmission hole 18 formed in theinner pipe 14 e. The configuration of theprojection 36 is set according to the configuration of thesound transmission hole 18. In this manner, thesound absorbing material 16 b is filled in the inner side of thesound transmission hole 18. - According to this configuration, in the noise eliminator 10 d of the present embodiment, when water flowing in from the exhaust system upstream, or water condensing in the interior of the noise eliminator 10 d attaches to the
sound transmission hole 18, it also naturally attaches to theprojection 36 of thesound absorbing material 16 b, disposed in the inner side of thesound transmission hole 18. The water attaching to theprojection 36 disperses to parts other than theprojection 36 of thesound absorbing material 16 b by the capillary phenomenon. Consequently, theprojection 36 of thesound absorbing material 16 b does not continue to be all wet. - Accordingly, even if a water film forms in the
sound transmission hole 18, the water constituting this water film is made to disperse to another part of thesound absorbing material 16 b by theprojection 36 of thesound absorbing material 16 b and thus the tension of the film forming in thesound transmission hole 18 is easily broken. Consequently, in thenoise eliminator 10 of the present embodiment, even when water flowing in from the exhaust system upstream or water condensing in the interior of the noise eliminator attaches to the sound transmission hole, formation of a water film in the sound transmission hole can be suppressed. - A noise eliminator 10 e according to the present embodiment will be described with reference to
FIGS. 11 , 12 and 13.FIG. 11 illustrates a cross section of an inner pipe;FIG. 12 illustrates an expanded sectional view of the section of the inner-pipe peripheral wall I inFIG. 11 ;FIG. 13 illustrates a view of the inner pipe having a cross section illustrated inFIG. 11 , as seen from the direction indicated by the arrow D; andFIG. 14 illustrates a cross section of an inner pipe in a noise eliminator according to a variation. The noise eliminator 10 d of the present embodiment differs from thenoise eliminator 10 of the first embodiment in that the inner pipe is provided with a drift member drifting the exhaust gas stream, as will be described in detail below. The same reference numerals are applied to parts corresponding to thenoise eliminator 10 of the first embodiment, and their explanation will not be repeated. - The
inner pipe 14 is provided with a drift member drifting the exhaust gas stream so that the exhaust gas stream does not impact directly against thesound transmission hole 18. The drift member is arranged inside theinner pipe 14; because the exhaust gas stream containing moisture does not directly impact against thesound transmission hole 18, fixing of the moisture contained in the exhaust gas stream to thesound transmission hole 18 is suppressed to a great extent. In thenoise eliminator 10 of the present embodiment, the drift member is arranged inside theinner pipe 14 to prevent the exhaust gas stream from impacting against thesound transmission hole 18; thus, formation of a water film in thesound transmission hole 18 can be suppressed. - According to the present embodiment, a
louver 38 as illustrated inFIG. 11 , is provided as the drift member in a protruding manner upstream of thesound transmission hole 18 in the inner-pipeinner wall 15. More specifically, thelouver 38 protrudes as illustrated inFIG. 12 , from the upstream end of thesound transmission hole 18 toward the inner pipe axis center F and at the same time in a manner inclined toward a downstream direction (direction indicated by the arrow D). - As indicated by the arrow J in
FIG. 12 , the exhaust gas stream flowing along the inner-pipeinner wall 15 is polarized upstream of thesound transmission hole 18 toward the side having the inner pipe axis center F by thelouver 38. Consequently, the exhaust gas stream flowing inside theinner pipe 14 f does not directly impact against thesound transmission hole 18 in the downstream of thelouver 38, and thus little of the moisture contained in the exhaust gas attaches to the walls of thesound transmission hole 18. - In addition, the
louver 38 is as illustrated inFIG. 13 , preferably arranged in a circular shape to cover the entire circumference of the inner-pipeinner wall 15. Thelouver 38 having such a circular configuration not only polarizes the exhaust gas stream inside theinner pipe 14 f, but also functions as a “rib” reinforcing theinner pipe 14 f. When theinner pipe 14 f is reinforced by thelouver 38, the stiffness of theinner pipe 14 f can be improved. As a result, the thickness of theperipheral wall 13 of theinner pipe 14 f can be set thinner. - In the noise eliminator 10 e of the present embodiment, as the drift member drifting the exhaust gas stream to prevent the exhaust gas stream from impacting directly against the
sound transmission hole 18, thelouver 38 protruding from the upstream end of thesound transmission hole 18 is provided, but the drift member is not limited to this configuration. - For example, as with a variation illustrated in
FIG. 14 , it is also preferable to provide within theinner pipe 14 g astream guide plate 40 guiding the exhaust gas stream to anarea 39 in which nosound transmission hole 18 is formed. Thestream guide plate 40 may be a plate-shaped member arranged in theinner wall 15 of anupstream side end 41 of theinner pipe 14 g, the plate being disposed in a manner inclined relative to the stream direction (indicated by the arrow D) of exhaust gas flowing into theinner pipe 14 g. Then, the exhaust gas stream flowing into theupstream side end 41 of theinner pipe 14 g is as indicated by the arrow K inFIG. 14 , polarized by thestream guide plate 40 and guided to the area 39 (area surrounded by the dashed line inFIG. 14 ) where nosound transmission hole 18 is formed. - The “
area 39 where nosound transmission hole 18 is formed” refers to an area, downstream of theupstream end 41 of theinner pipe 14 g, and excluding the area 43 (indicated by the dotted line inFIG. 14 ) where thesound transmission hole 18 is formed. Thestream guide plate 40 polarizes the exhaust gas stream flowing into theinner pipe 14 g so that the exhaust gas stream avoids this “area 43 where thesound transmission hole 18 is formed”. - In this way, the exhaust gas stream does not directly impact the “
area 43 in which thesound transmission hole 18 is formed”. Consequently, very little of the moisture contained in the exhaust gas attaches to thesound transmission hole 18. - As described above, in the noise eliminator 10 e of the present embodiment, the
louver 38 protruding from the upstream side of thesound transmission hole 18 is arranged inside theinner pipe 14 g, or thestream guide plate 40 is arranged in theupstream side end 41, and thus very little moisture attaches to thesound transmission hole 18. Consequently, formation of a water film in the sound transmission hole is suppressed. - A
noise eliminator 10 f according to the present embodiment will be described with reference toFIG. 15 .FIG. 15 schematically illustrates a cross section of the noise eliminator. Thenoise eliminator 10 f of the present embodiment differs from thenoise eliminator 10 of the first embodiment in that a swirling stream (vortex) generation member is provided along the inner pipe inner wall for generating a swirling stream, and will be described in detail below. The same reference numerals are applied to parts corresponding to thenoise eliminator 10 of the first embodiment, and their explanation will not be repeated. - According to the present embodiment, the swirling
stream generation member 44 is, as illustrated inFIG. 15 , a plate-shaped member having a twisted configuration and arranged in theupstream end 41 inside theinner pipe 14 h. This twisted plate-shaped member generates a swirling stream swirling along the inner-pipeinner wall 15. As indicated by the arrow b, the exhaust gas stream flowing into theupstream end 41 of theinner pipe 14 h swirls around the inner pipe axis center F by the plate-shaped member. This swirling exhaust gas stream (swirling stream) flows, as indicated by the arrow L inFIG. 15 , in a downstream direction while swirling along the inner-pipeinner wall 15. Acting on the exhaust gas swirling inside theinner pipe 14 h is a centrifugal force working toward the inner-pipeinner wall 15 around the axis center of theinner pipe 14 h. - Accordingly, in the
noise eliminator 10 f of the present embodiment, even if a water film forms in the sound transmission hole, the exhaust gas is pressed against the water film and thus the film tension is easily broken. Consequently, in thenoise eliminator 10 of the present embodiment, formation of a water film in the sound transmission hole can be suppressed. - Here, it is also preferable that the
sound transmission hole 18 f is, as illustrated inFIG. 15 , formed to have a configuration along the flow of the generated swirling stream. More specifically, thesound transmission hole 18 is set so that the stream direction (indicated by the arrow L) of the swirling stream agrees with the longitudinal direction of thesound transmission hole 18 f. - When the
sound transmission hole 18 f is configured in this manner, even if a water film forms in thesound transmission hole 18 f, the water film is polarized and deformed in the longitudinal direction of thesound transmission hole 18 f by the exhaust gas stream (swirling stream) flowing along the inner-pipeinner wall 15, and, because the film includes thin patches, the film tension is easily broken. - A
noise eliminator 10 g according to the present embodiment will be described with reference toFIGS. 16 to 19 .FIG. 16 schematically illustrates a cross section of the noise eliminator;FIG. 17 illustrates an exemplary vortex generation member arranged in the noise eliminator;FIG. 18 illustrates a cross section of an inner pipe in a noise eliminator according to a variation; andFIG. 19 illustrates a view of the inner pipe having a cross section illustrated inFIG. 18 , as seen from the direction indicated by the arrow D. The noise eliminator 10 g of the present embodiment differs from thenoise eliminator 10 of the first embodiment in being provide with a vortex generation member generating a vortex along the inner-pipe inner wall, and will be described in detail below. The same reference numerals are applied to parts corresponding to thenoise eliminator 10 of the first embodiment, and their explanation will not be repeated. - The
inner pipe 14 i is provided with a vortex generation member generating a vortex in the vicinity of theinner wall 15 of theinner pipe 14 i. The vortex generation member produces avortex 48 upstream of thesound transmission hole 18. The producedvortex 48 flows downstream along the inner wall of theinner pipe 14 towards thesound transmission hole 18. The turbulent flow of thevortex 48 as it reaches thesound transmission hole 18 suppresses formation of water films in thesound transmission hole 18, and, upon impact, acts to break up any films that may have formed. In the noise eliminator 10 g of the present embodiment, because theinner pipe 14 i is provided with the vortex generation member to produce a vortex in the vicinity of the inner-pipeinner wall 15, formation of a water film in the sound transmission hole can be suppressed. - According to the present embodiment, as the vortex generation member, a Karman
vortex generation member 46 is, as illustrated inFIG. 16 , arranged in theupstream end 41 of theinner pipe 14 i. The Karmanvortex generation member 46 can be, as illustrated inFIG. 17 , composed of a plate-shaped member having some thickness, for example. The member is disposed inside theinner pipe 14 i so that the axis center F of theinner pipe 14 i penetrates through the member. - The exhaust gas stream flowing into the
inner pipe 14 i from the direction indicated by the arrow D is divided into two streams (an upper stream and a lower stream indicated by the arrows M1 and M2, respectively, inFIG. 16 ) by the Karmanvortex generation member 46. The two streams break away at adownstream end 46 e of the Karmanvortex generation member 46 and alternately produce avortex 48. ThisKarman vortex 48 flows to the downstream side and reaches thesound transmission hole 18. The turbulent flow of thevortex 48 suppresses formation of water films in thesound transmission hole 18, and acts to break up any films that do form. - In the noise eliminator 10 g of the present embodiment, the Karman
vortex generation member 48 produces a vortex in the vicinity of the inner-pipeinner wall 15, but the vortex generation member is not limited to this configuration. - For example, as with the variation illustrated in
FIGS. 18 and 19 , it is also preferable that there is arranged aprotrusion 50 generating avortex 51 in the vicinity of the inner-pipeinner wall 15. Aprotrusion 50 may be, as illustrated inFIG. 18 , arranged for eachsound transmission hole 18 in the upstream side of the hole. Also, theprotrusions 50 project, as illustrated inFIG. 19 , from the inner-pipeinner wall 15 toward the inner-pipe axis center F. Theprotrusion 50 is configured so that the flow along theinner wall 15 of theinner pipe 14 j can be separated away from the boundary layer as much as possible. - Of the exhaust gas stream flowing from a direction indicated by the arrow D into the
inner pipe 14 j, the flow (indicated by the arrow N inFIG. 18 ) along the inner-pipeinner wall 15 collides with theprotrusion 50 and separates from theinner wall 15, thus generating a vortex 51 (turbulent flow). Thisvortex 51 reaches thesound transmission hole 18 residing in the upstream side of theprotrusion 50. Accordingly, formation of a water film in the sound transmission hole can be further suppressed. - A
noise eliminator 10 h according to the present embodiment will be described with reference toFIGS. 20 to 22.FIG. 20 schematically illustrates a vertical section of the noise eliminator;FIG. 21 illustrates a vertical section of an inner pipe in a noise eliminator according to a variation; andFIG. 22 illustrates a view of the inner pipe having a cross section illustrated inFIG. 21 , as seen from the direction indicated by the arrow D. Thenoise eliminator 10 of the present embodiment differs from thenoise eliminator 10 of the first embodiment in that stream guide means are provided for directing a portion of the exhaust gas flowing into the inner pipe out from the upstream sound transmission hole to the sound absorbing chamber. These stream guide means will be described in detail below, but the same reference numerals are applied to parts corresponding to thenoise eliminator 10 of the first embodiment, and their explanation will not be repeated. - The stream guide means cause a portion of the exhaust gas flowing inside the
inner pipe 14 to flow out from inside theinner pipe 14 through thesound transmission hole 18 g in the upstream side to thesound absorbing chamber 17. More specifically, in thesound transmission hole 18 g in the upstream side, the stream guide means produce an exhaust gas stream flowing from inside theinner pipe 14 to the sound absorbing chamber. 17. Thesound absorbing chamber 17 is a hermetically-closed space surrounded by the inner-pipe outer wall and outer-shell inner wall, with the exception of the sound transmission holes 18 g and 18 h, and the exhaust gas flowing out from thesound transmission hole 18 g in the upstream side to thesound absorbing chamber 17 flows back from thesound transmission hole 18 h in the downstream side into theinner pipe 14. In thesound transmission hole 18 h in the downstream side, there is produced an exhaust gas stream flowing from thesound absorbing chamber 17 into theinner pipe 14. - When the stream guide means are arranged in the
noise eliminator 10 h, an exhaust gas stream can be produced in such a manner that a portion of the streams flows out from inside theinner pipe 14 through thesound transmission hole 18 g in the upstream side to thesound absorbing chamber 17 and flows back through thesound transmission hole 18 h in the downstream side into theinner pipe 14. Because the exhaust gas streams flows through both the upstream and downstream sound transmission holes 18 g and 18 h, formation of water films in the sound transmission holes 18 g and 18 h is suppressed, and any films that do form tend to be broken by the exhaust gas stream flowing through the sound transmission holes 18 g and 18 h. Accordingly, in thenoise eliminator 10 h of the present embodiment, formation of a water film in the sound transmission hole can be further suppressed. - According to the present embodiment, a narrowed
section 52 as illustrated inFIG. 20 is formed in theinner pipe 14 k as the stream guide means. The narrowedsection 52 is a portion in which the cross sectional area (cross section orthogonal to the axis center F of the inner pipe 14) of the stream path formed inside theinner pipe 14 k is smaller than elsewhere, and disposed in the path of theinner pipe 14 k. The sound transmission holes 18 g and 18 h are formed upstream and downstream relative to this narrowedsection 52, respectively. - When exhaust gas flows in from the direction indicated by the arrow D, the pressure in the upstream side relative to the narrowed
section 52 in theinner pipe 14 k increase. On the other hand, downstream of the narrowedsection 52 in theinner pipe 14 k, the pressure becomes lower than in upstream side relative to the narrowedsection 52. In this way, when the narrowedsection 52 is formed in theinner pipe 14 k, a pressure differential between the flow upstream and downstream of the narrowedsection 52 is created, causing a portion of the exhaust gas flowing upstream of the narrowedsection 52 in theinner pipe 14 k to flow out from the upstream-sidesound transmission hole 18 to thesound absorbing chamber 17. Further, the exhaust gas flowing out to thesound absorbing chamber 17 flows, as indicated by the arrow P inFIG. 20 , in a downstream direction inside thesound absorbing chamber 17, and then flows through the downstreamsound transmission hole 18 h into the downstream side relative to the narrowedsection 52 in theinner pipe 14 k. - In this way, in the
noise eliminator 10 h of the present embodiment, because the narrowedsection 52 is arranged in theinner pipe 14 k, exhaust gas streams flowing from inside theinner pipe 14 k through thesound transmission hole 18 g in the upstream side into thesound absorbing chamber 17, and flowing from thesound absorbing chamber 17 through thesound transmission hole 18 h in the downstream side into theinner pipe 14 k, are produced. Accordingly, water films rarely form in the upstream and downstream sound transmission holes 18 g and 18 h, and any films that do form are easily broken by the exhaust gas stream flowing through the sound transmission holes 18 g and 18 h. - In the
noise eliminator 10 h of the present embodiment, the formation of the narrowedsection 52 in theinner pipe 14 k allows a portion of the exhaust gas to flow out through the upstreamsound transmission hole 18 g into thesound absorbing chamber 17, but the stream guide means are not limited to this configuration. - For example, as with the variation illustrated in
FIGS. 21 and 22 , it is also preferable that there is arranged aduct 54 corresponding to the upstreamsound transmission hole 18 g. Theduct 54 may be, as illustrated inFIG. 21 , arranged in theinner wall 15 of the inner pipe 141 in a manner corresponding to each of the upstream sound transmission holes 18. Also, theduct 54 may protrude, as illustrated inFIG. 22 , from theinner wall 15 of the inner pipe 141 toward the axis center F of the inner pipe 141, and have an opening facing the upstream side. - Of the exhaust gas streams flowing from a direction indicated by the arrow D into the inner pipe 141, the stream indicated by the arrow Q in
FIG. 21 , which flows along the inner-pipeinner wall 15, flows from the opening of theduct 54 through the sound transmission hole 18 (in the upstream side) and flows out into thesound absorbing chamber 17. Because the exhaust gas flowing out into thesound absorbing chamber 17 raises the pressure inside thesound absorbing chamber 17, the exhaust gas flowing out into thesound absorbing chamber 17 flows back, as indicated by the arrow R inFIG. 21 , through thesound transmission hole 18 h in the downstream side into the inner pipe 141. - In this manner, providing for each upstream sound transmission hole 18 a
duct 54 having an upstream opening can produce the exhaust gas streams flowing through the upstream and downstream sound transmission holes 18 i. As a result, formation of a water film in the sound transmission hole can be further suppressed. - A
noise eliminator 10 i according to the present embodiment will be described with reference toFIG. 23 .FIG. 23 schematically illustrates the noise eliminator and its peripheral device. Thenoise eliminator 10 i of the present embodiment is different from thenoise eliminator 10 of the first embodiment in being provided with gas injection means for injecting gas into the sound absorbing chamber, and will be described in detail below. The same reference numerals are applied to parts corresponding to thenoise eliminator 10 of the first embodiment, and their explanation will not be repeated. - Separately from the exhaust gas stream flowing from the upstream of the exhaust system into the
inner pipe 14, the gas injection means injects gas from the outside of thenoise eliminator 10 i into thesound absorbing chamber 17. Because the pressure of the injected gas is greater than the pressure inside theinner pipe 14, when gas is injected into thesound absorbing chamber 17, the gas inside thesound absorbing chamber 17 flows through thesound transmission hole 18 into theinner pipe 14. In this way, a stream flowing from inside thesound absorbing chamber 17 through thesound transmission hole 18 and into theinner pipe 14 can be produced. - Consequently, water film rarely form in the
sound transmission hole 18, and, even should such a film form, the stream flowing through thesound transmission hole 18 acts to break up the film. As a result, in thenoise eliminator 10 according to the present embodiment, formation of water films in the sound transmission hole can be suppressed. - According to the present embodiment, a
bypass stream path 60 which bypasses thefuel cell 82 and directly connects the oxidizinggas supplying path 87 and the interior of thesound absorbing chamber 17 as illustrated inFIG. 23 is provided as the gas injection means. One end of thebypass stream path 60 is connected to agas outlet 57 arranged in the oxidizinggas supplying path 87 connecting ablower 86 andfuel cell body 82 a; and the other end thereof is connected to agas inlet 58 arranged in theouter shell 12 c. By connecting thebypass stream path 60 in this manner, the oxidizinggas supplying path 87 is made to communicate with thesound absorbing chamber 17 inside theouter shell 12. - Referring to
FIG. 23 , when theblower 86 supplies, as indicated by the arrow S, oxidizing gas (air) through the oxidizinggas supplying path 87 to thefuel cell body 82 a, the oxidizing gas is simultaneously supplied to the bypass stream path 60 (indicated by the arrow T inFIG. 23 ). The oxidizing gas supplied to thebypass stream path 60 flows, as indicated by the arrow U, through thegas inlet 58 of theouter shell 12 into thesound absorbing chamber 17. Meanwhile, the oxidizing gas supplied to thefuel cell body 82 a is discharged as oxidizing gas from thefuel cell body 82 a, and subjected to flow rate adjustment by anadjustment valve 82 b, and flows, as indicated by the arrow D, into theinner pipe 14 of thenoise eliminator 10 i. - Here, the pressure of oxidizing gas flowing in the bypass stream path 60 (the pressure of oxidizing gas injected into the sound absorbing chamber) is set higher than the pressure of exhaust gas flowing in the
inner pipe 14, so the oxidizing gas flowing through thegas inlet 58 into thesound absorbing chamber 17 flows from thesound absorbing chamber 17 through thesound transmission hole 18 into theinner pipe 14. - In this way, the
bypass stream path 60 directly connecting the oxidizinggas supplying path 87 outside thenoise eliminator 10 and the interior of thesound absorbing chamber 17 is provided in thenoise eliminator 10 of the present embodiment, such that a gas stream flowing from thesound absorbing chamber 17 through thesound transmission hole 18 into theinner pipe 14 can be formed. Accordingly, formation of a water film in the sound transmission hole can be further suppressed. - According to the present embodiment, oxidizing gas is removed from the oxidizing gas supplying path to the bypass stream path and injected into the sound absorbing chamber, but the configuration is not limited thereto. For example, it is also preferable that a gas outlet is arranged in an anode purge valve intermittently discharging anode gas (hydrogen) and is connected to the bypass stream path, whereby the anode gas is injected into the sound absorbing chamber. With this configuration, gas is intermittently supplied to the sound absorbing chamber and produces a pressure wave when injected, and any water films forming in the
sound transmission hole 18 can be broken up by this pressure wave. - It is also preferable that a valve (not illustrated) which can be opened and closed instantaneously be provided in the
bypass stream path 60. The instantaneous opening or closing of this valve produces a pressure wave in the oxidizing gas downstream of the valve. When this pressure wave propagates through thesound absorbing chamber 17 to thesound transmission hole 18. - It is also preferable that the
adjustment valve 82 b is opened or closed instantaneously. Such instantaneous opening and closing of theadjustment valve 82 b produces a pressure wave as indicated by the arrow D in the exhaust gas flowing into theinner pipe 14. This pressure wave propagates from theinner pipe 14 to thesound transmission hole 18, and again acts to break up any water films forming in the sound transmission hole. - A noise eliminator 10 j according to the present embodiment will be described with reference to
FIGS. 24 and 25 .FIG. 24 illustrates a vertical section of aninner pipe 14, whileFIG. 25 illustrates a view of theinner pipe 14 having the cross section illustrated inFIG. 24 , as seen from the direction indicated by the arrow D. The noise eliminator 10 j of the present embodiment differs from thenoise eliminator 10 of the first embodiment in that the sound transmission hole and the peripheral part thereof are formed projecting towards the axis center F of the inner pipe, as will be described in detail below. The same reference numerals are applied to parts corresponding to thenoise eliminator 10 of the first embodiment, and their explanation will not be repeated. - According to the present embodiment, the
sound transmission hole 18 i and itsperipheral part 62 are, as illustrated inFIGS. 24 and 25 , arranged to project from theinner wall 15 of theinner pipe 14 m toward the inner-pipe axis center F. The exhaust gas (indicated by the arrow V) flowing along theinner wall 15 of theinner pipe 14 is polarized toward the inner-pipe axis center F by theperipheral part 62 of thesound transmission hole 18 i, such that a contracted flow area 64 (surrounded by the two-dot chain line inFIG. 24 ) having a relatively rapid flow is produced between thesound transmission hole 18 i and the inner-pipe axis center F. That is, thesound transmission hole 18 i is exposed to the rapidly flowing exhaust gas stream. - In this manner, in the
noise eliminator 10 i of the present embodiment, even when a water film forms in thesound transmission hole 18 i, because thesound transmission hole 18 i is exposed to a relatively rapid flow, the water film is polarized towards a downstream direction and deformed, such that portions of the film are thinner and the film is, thus, easily broken or dispersed. Consequently, formation of water films in the sound transmission hole can be further suppressed. - A
noise eliminator 10 k according to the present embodiment will be described with reference toFIGS. 26 and 27 .FIG. 26 schematically illustrates a vertical cross section of the noise eliminator, whileFIG. 27 schematically illustrates a perspective view of an inner case constituting the noise eliminator. Thenoise eliminator 10 k of the present embodiment differs from thenoise eliminator 10 of the first embodiment in including an outer shell allowing exhaust gas to flow therethrough and an inner case, having a plurality of through holes formed in a wall surface thereof, with a sound absorbing material filled in the interior thereof, the inner case being disposed over the entire cross section of the outer-shell stream path, and will be described in detail below. - The
inner case 66 is as illustrated inFIG. 27 , a hard case of a substantially rectangular shape having a plurality of throughholes 18 j formed on thewall surface 68 thereof. In more detail, in thewall surface 68 constituting theinner case 66, thesound transmission hole 18 j is formed in theupstream wall surface 68 a and thedownstream wall surface 68 b facing thewall surface 68 a; gas can flow therethrough from the upstream side wall surface 68 a to the downstreamside wall surface 68 b. Thesound absorbing material 16 is filled in the inner side of the innercase wall surface 68, i.e., inside theinner case 66, which functions as asound absorbing chamber 17. - The
inner case 66 described above is, as illustrated inFIG. 26 , received and held in the inner side of theouter shell 12 d. Astream path 70 is formed in the inner side of theouter shell 12 d, and theinner case 66 is disposed so as to seal thisstream path 70. In more detail, the wall surface 68 (the upstream side wall surface 68 a and the downstreamside wall surface 68 b) of theinner case 66 having thesound transmission hole 18 j is disposed over the entire cross section of thestream path 70 inside theouter shell 12 d. - When the
noise eliminator 10 k is configured in this manner, all the exhaust gas flowing through theouter shell 12 d flows, as indicated by the arrow W, through the throughhole 18 j of the inner-case wall surface 68 and thesound absorbing chamber 17 residing therein. Accordingly, in thenoise eliminator 10 k of the present embodiment, formation of a water film in the throughhole 18 j can be suppressed. - It is preferable that the configuration of the
inner case 66 andouter shell 12 d is set so that the area of thewall surface 68 having the throughhole 18 j of theinner case 66 is maximized. When the area of thewall surface 68 having the throughhole 18 j of theinner case 66 is maximized and the number of the throughholes 18 j is set accordingly, the pressure loss caused by exhaust gas flowing through theinner case 66 can be reduced. - A
noise eliminator 10 m according to the present embodiment will be described with reference toFIGS. 28 and 29 .FIG. 28 illustrates a vertical section of the noise eliminator, whileFIG. 29 illustrates a view of a plate-shaped member constituting the noise eliminator, as seen from the direction indicated by the arrow D. Thenoise eliminator 10 m of the present embodiment is differs from thenoise eliminator 10 of the first embodiment in that it includes a shell allowing exhaust gas to flow therethrough and a plate-shaped member having a plurality of through holes formed therein, the plate-shaped member partitioning the interior of the shell by a face thereof orthogonal to the direction of exhaust gas stream. Thenoise eliminator 10 m will be described in detail below. - The plate-shaped
member 72 is a hard plate member having a substantially circular shape as illustrated inFIG. 29 . A plurality of throughholes 18 k are formed in awall surface 73 thereof. Meanwhile, astream path 75 having a substantially circular-shaped cross section is, as illustrated inFIG. 28 , formed inside theshell 74. A plurality of the plate-shapedmembers 72 are arranged inside theshell 74 so as to divide thestream path 75 inside theshell 74 by a face thereof orthogonal to the stream direction (direction indicated by the arrow D) of exhaust gas. That is, the throughhole 18 k of the plate-shapedmember 72 has the same through direction as the direction of exhaust gas stream. - The exhaust gas flowing in from the direction indicated by the arrow D flows, as indicated by the arrow D, through the through
hole 18 k of the plate-shapedmember 72. The exhaust gas stream indicated by the arrow D is a turbulent flow produced upstream in the exhaust system, and this turbulent flow is rectified when the exhaust gas flows through the plurality of throughholes 18 k formed in the plate-shapedmember 72. In this way, the turbulent flow is rectified each time it passes through the throughholes 18 k of each plate-shaped member, whereby the sound propagating from the exhaust system upstream to the interior of theshell 74 is silenced. - In the
noise eliminator 10 m of the present embodiment, the flowing—in exhaust gas is reliably directed through the throughhole 18 k of the plate-shapedmember 72, and formation of water films in the throughhole 18 k is thereby suppressed. As a result, a desired noise elimination performance can be achieved without using a sound absorbing material. - As described above, the noise eliminator for a fuel cell according to the present invention is useful as a noise eliminator in an exhaust system of a fuel cell.
Claims (20)
1. A noise eliminator for a fuel cell installed in an exhaust system discharging exhaust gas from a fuel cell, the noise eliminator comprising:
an inner pipe having a plurality of sound transmission holes formed in a peripheral wall thereof and allowing exhaust gas to flow therethrough; and
an outer shell, arranged to surround the inner pipe up to a prescribed distance from the peripheral wall, and constituting a sound absorbing chamber with a sound absorbing material filled in a space between the outer shell and the inner pipe,
wherein the sound transmission hole has an inner diameter of 3 mm or greater and a depth of 1.2 mm or less.
2. The noise eliminator for a fuel cell according to claim 1 , wherein the peripheral part of the sound transmission hole in the inner pipe is formed with a wall thickness thinner than that of other parts of the sound transmission hole.
3. The noise eliminator for a fuel cell according to claim 1 , wherein a rib reinforcing the inner pipe is formed between the sound transmission holes.
4. A noise eliminator for a fuel cell installed in an exhaust system discharging exhaust gas from a fuel cell, the noise eliminator comprising:
an inner pipe having a plurality of sound transmission holes formed in a peripheral wall thereof and allowing exhaust gas to flow therethrough; and
an outer shell, arranged to surround the inner pipe up to a prescribed distance from the peripheral wall, and constituting a sound absorbing chamber with a sound absorbing material filled in a space between the outer shell and the inner pipe,
wherein the sound transmission hole is formed in the shape of an oval having a longitudinal axis along the axis direction of the inner pipe.
5. The noise eliminator for a fuel cell according to claim 4 , wherein the direction of the longitudinal axis of the oval being the sound transmission hole is substantially parallel to the axis of the inner pipe.
6. A noise eliminator for a fuel cell installed in an exhaust system discharging exhaust gas from a fuel cell, the noise eliminator comprising:
an inner pipe having a plurality of sound transmission holes formed in a peripheral wall thereof and allowing exhaust gas to flow therethrough; and
an outer shell, arranged to surround the inner pipe up to a prescribed distance from the peripheral wall, and constituting a sound absorbing chamber with a sound absorbing material filled in a space between the outer shell and the inner pipe,
wherein there is formed a groove connecting the adjoining sound transmission holes.
7. A noise eliminator for a fuel cell installed in an exhaust system discharging exhaust gas from a fuel cell, the noise eliminator comprising:
an inner pipe having a plurality of sound transmission holes formed in a peripheral wall thereof and allowing exhaust gas to flow therethrough; and
an outer shell, arranged to surround the inner pipe up to a prescribed distance from the peripheral wall, and constituting a sound absorbing chamber with a sound absorbing material filled in a space between the outer shell and the inner pipe,
wherein the inner wall of the sound transmission hole is formed in a saw-tooth shape.
8. A noise eliminator for a fuel cell installed in an exhaust system discharging exhaust gas from a fuel cell, the noise eliminator comprising:
an inner pipe having a plurality of sound transmission holes formed in a peripheral wall thereof and allowing exhaust gas to flow therethrough; and
an outer shell, arranged to surround the inner pipe up to a prescribed distance from the peripheral wall, and constituting a sound absorbing chamber with a sound absorbing material filled in a space between the outer shell and the inner pipe,
wherein a water repellant layer is formed in the inner wall of the sound transmission hole.
9. A noise eliminator for a fuel cell installed in an exhaust system discharging exhaust gas from a fuel cell, the noise eliminator comprising:
an inner pipe having a plurality of sound transmission holes formed in a peripheral wall thereof and allowing exhaust gas to flow therethrough; and
an outer shell, arranged to surround the inner pipe up to a prescribed distance from the peripheral wall, and constituting a sound absorbing chamber with a sound absorbing material filled in a space between the outer shell and the inner pipe,
wherein a sound absorbing material is filled in the inner side of the inner wall of the sound transmission hole.
10. A noise eliminator for a fuel cell installed in an exhaust system discharging exhaust gas from a fuel cell, the noise eliminator comprising:
an inner pipe having a plurality of sound transmission holes formed in a peripheral wall thereof and allowing exhaust gas to flow therethrough; and
an outer shell, arranged to surround the inner pipe up to a prescribed distance from the peripheral wall, and constituting a sound absorbing chamber with a sound absorbing material filled in a space between the outer shell and the inner pipe,
wherein the inner pipe is provided with a stream drift member drifting an exhaust gas stream in such a manner that the exhaust gas stream is prevented from directly impacting the sound transmission hole, and
wherein the stream drift member is a louver in the inner-pipe inner wall, protruding in a manner inclined from the upstream side of the sound transmission hole towards a downstream direction.
11. A noise eliminator for a fuel cell installed in an exhaust system discharging exhaust gas from a fuel cell, the noise eliminator comprising:
an inner pipe having a plurality of sound transmission holes formed in a peripheral wall thereof and allowing exhaust gas to flow therethrough; and
an outer shell, arranged to surround the inner pipe up to a prescribed distance from the peripheral wall, and constituting a sound absorbing chamber with a sound absorbing material filled in a space between the outer shell and the inner pipe,
wherein the inner pipe is provided with a stream drift member drifting an exhaust gas stream in such a manner that the exhaust gas stream is prevented from directly impacting the sound transmission hole, and
wherein the stream drift member is a stream guide plate, provided at an upstream end of the inner pipe, and guiding the exhaust gas stream to an area where no sound transmission hole is formed.
12. A noise eliminator for a fuel cell installed in an exhaust system discharging exhaust gas from a fuel cell, the noise eliminator comprising:
an inner pipe having a plurality of sound transmission holes formed in a peripheral wall thereof and allowing exhaust gas to flow therethrough; and
an outer shell, arranged to surround the inner pipe up to a prescribed distance from the peripheral wall, and constituting a sound absorbing chamber with a sound absorbing material filled in a space between the outer shell and the inner pipe,
wherein a swirling flow generation member generating a swirling flow along the inner-pipe inner wall is provided in an upstream end of the inner pipe.
13. A noise eliminator for a fuel cell installed in an exhaust system discharging exhaust gas from a fuel cell, the noise eliminator comprising:
an inner pipe having a plurality of sound transmission holes formed in a peripheral wall thereof and allowing exhaust gas to flow therethrough; and
an outer shell, arranged to surround the inner pipe up to a prescribed distance from the peripheral wall, and constituting a sound absorbing chamber with a sound absorbing material filled in a space between the outer shell and the inner pipe,
wherein a vortex generation member generating a vortex in the vicinity of the inner-pipe inner wall is provided in the inner pipe.
14. A noise eliminator for a fuel cell installed in an exhaust system discharging exhaust gas from a fuel cell, the noise eliminator comprising:
an inner pipe having a plurality of sound transmission holes formed in a peripheral wall thereof and allowing exhaust gas to flow therethrough; and
an outer shell, arranged to surround the inner pipe up to a prescribed distance from the peripheral wall, and constituting a sound absorbing chamber with a sound absorbing material filled in a space between the outer shell and the inner pipe,
the noise eliminator further comprising stream guide means for causing a portion of the exhaust gas flowing into the inner pipe to flow out from inside the inner pipe through the upstream-side sound transmission holes to the sound absorbing chamber,
wherein the exhaust gas flowing out to the sound absorbing chamber flows through the downstream-side sound transmission holes back into the inner pipe.
15. The noise eliminator for a fuel cell according to claim 14 , wherein the stream guide means is a narrowed portion formed in the path of the inner pipe.
16. The noise eliminator for a fuel cell according to claim 14 , wherein the stream guide means is a duct arranged in the inner-pipe inner wall in a manner corresponding to the upstream-side sound transmission hole.
17. A noise eliminator for a fuel cell installed in an exhaust system discharging exhaust gas from a fuel cell, the noise eliminator comprising:
an inner pipe having a plurality of sound transmission holes formed in a peripheral wall thereof and allowing exhaust gas to flow therethrough; and
an outer shell, arranged to surround the inner pipe up to a prescribed distance from the peripheral wall, and constituting a sound absorbing chamber with a sound absorbing material filled in a space between the outer shell and the inner pipe,
the noise eliminator further comprising gas injection means for injecting gas from outside the noise eliminator directly to the sound absorbing chamber so that gas flows from the sound absorbing chamber through the sound transmission holes into the inner pipe.
18. A noise eliminator for a fuel cell installed in an exhaust system discharging exhaust gas from a fuel cell, the noise eliminator comprising:
an inner pipe having a plurality of sound transmission holes formed in a peripheral wall thereof and allowing exhaust gas to flow therethrough; and
an outer shell, arranged to surround the inner pipe up to a prescribed distance from the peripheral wall, and constituting a sound absorbing chamber with a sound absorbing material filled in a space between the outer shell and the inner pipe,
wherein the sound transmission hole and a peripheral part thereof are formed in a manner projecting towards the axis center of the inner pipe.
19. A noise eliminator for a fuel cell installed in an exhaust system discharging exhaust gas from a fuel cell, the noise eliminator comprising:
an outer shell allowing exhaust gas to flow therethrough; and
an inner case having a plurality of through holes formed in a peripheral wall thereof and constituting a sound absorbing chamber with a sound absorbing material filled in the interior thereof,
wherein the inner case is arranged over the entire stream path cross section of the outer shell such that all the exhaust gas flowing through the outer shell flows through the interior of the inner case.
20. (canceled)
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2005-185371 | 2005-06-24 | ||
JP2005185371A JP2007005178A (en) | 2005-06-24 | 2005-06-24 | Noise eliminator for fuel cell |
PCT/JP2006/312841 WO2006137570A1 (en) | 2005-06-24 | 2006-06-21 | Silencer for fuel cell |
Publications (1)
Publication Number | Publication Date |
---|---|
US20090045006A1 true US20090045006A1 (en) | 2009-02-19 |
Family
ID=37570581
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US11/920,432 Abandoned US20090045006A1 (en) | 2005-06-24 | 2006-06-21 | Noise Eliminator for Fuel Cell |
Country Status (5)
Country | Link |
---|---|
US (1) | US20090045006A1 (en) |
JP (1) | JP2007005178A (en) |
CN (1) | CN100549371C (en) |
DE (1) | DE112006001389T5 (en) |
WO (1) | WO2006137570A1 (en) |
Cited By (17)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20080141667A1 (en) * | 2006-12-18 | 2008-06-19 | Gm Global Technology Operations, Inc. | Fuel-cell exhaust system |
US20090078498A1 (en) * | 2007-09-26 | 2009-03-26 | Darrin Woods | Seamless in-line airboat muffler |
CN101907009A (en) * | 2010-07-19 | 2010-12-08 | 中国人民解放军重庆通信学院 | Impedance composite water-cooled muffler for diesel generator set |
CN104074585A (en) * | 2014-07-04 | 2014-10-01 | 重庆长安汽车股份有限公司 | Silencer drainage structure |
WO2016087852A1 (en) * | 2014-12-03 | 2016-06-09 | Intelligent Energy Limited | Exhaust assembly |
US20160197362A1 (en) * | 2013-09-20 | 2016-07-07 | Bayerische Motoren Werke Aktiengesellschaft | Exhaust Gas System and Motor Vehicle Having an Exhaust Gas System |
US20160220775A1 (en) * | 2013-09-23 | 2016-08-04 | Fisher & Paykel Healthcare Limited | Nasal cannula with turbulation elements |
CN107636315A (en) * | 2017-03-28 | 2018-01-26 | 美的集团股份有限公司 | Pedestal and bladeless fan |
US20180073412A1 (en) * | 2016-09-12 | 2018-03-15 | Volvo Car Corporation | Combined heat exchanger and exhaust silencer |
US10233814B2 (en) | 2015-08-10 | 2019-03-19 | Faurecia Emissions Control Technologies, Germany Gmbh | Component of an exhaust system |
US10243227B2 (en) * | 2016-12-06 | 2019-03-26 | Hyundai Motor Company | Apparatus for reducing hydrogen concentration in exhaust gas of an exhaust system for a fuel cell vehicle |
GB2572644A (en) * | 2018-04-06 | 2019-10-09 | Jaguar Land Rover Ltd | An attenuator for a fluid duct |
WO2021016160A1 (en) * | 2019-07-23 | 2021-01-28 | Tenneco Automotive Operating Company Inc. | Vehicle exhaust system |
CN112683539A (en) * | 2020-12-15 | 2021-04-20 | 中航工程集成设备有限公司 | Exhaust metal runner structure for aircraft engine test |
US20210239017A1 (en) * | 2020-02-03 | 2021-08-05 | Faurecia Emissions Control Technologies, Usa, Llc | Exhaust system component |
EP4102600A1 (en) * | 2021-06-10 | 2022-12-14 | NOVARES France | Exhaust silencer for a fuel cell |
EP4290058A1 (en) * | 2022-06-09 | 2023-12-13 | Purem GmbH | Silencer |
Families Citing this family (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2007207705A (en) * | 2006-02-06 | 2007-08-16 | Kojima Press Co Ltd | Silencer for fuel cell |
JP5102574B2 (en) * | 2007-10-02 | 2012-12-19 | 本田技研工業株式会社 | Fuel cell system |
JP5111126B2 (en) * | 2008-01-22 | 2012-12-26 | 本田技研工業株式会社 | Muffler for fuel cell car |
CN101363346B (en) * | 2008-09-23 | 2010-06-09 | 张荣初 | Low frequency self-cleaning noise deadener and method for making same |
KR101306818B1 (en) * | 2011-01-13 | 2013-09-10 | 세종공업 주식회사 | Noise eliminator for fuel cell |
JP5243634B1 (en) * | 2012-03-26 | 2013-07-24 | 増山 征男 | Exhaust promotion device using heat engine exhaust |
JP5243647B1 (en) * | 2012-06-08 | 2013-07-24 | 増山 征男 | Exhaust promotion device for heat engine |
CN103280214B (en) * | 2012-11-21 | 2018-07-10 | 尼米仪器株式会社 | A kind of hybrid vehicle muffler |
JP6180381B2 (en) * | 2014-07-16 | 2017-08-16 | 本田技研工業株式会社 | Fuel cell stack |
CN104564241A (en) * | 2015-01-23 | 2015-04-29 | 安徽江淮汽车股份有限公司 | Exhaust muffler |
DE102019101418A1 (en) * | 2018-01-26 | 2019-08-01 | Futaba Industrial Co., Ltd. | silencer |
Citations (19)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1844106A (en) * | 1929-05-08 | 1932-02-09 | Burgess Lab Inc C F | Exhaust muffler |
US1912544A (en) * | 1929-11-02 | 1933-06-06 | Burgess Lab Inc C F | Method for tightly packing materials and product formed thereby |
US1921468A (en) * | 1929-11-08 | 1933-08-08 | Burgess Lab Inc C F | Muffler |
US2046193A (en) * | 1931-01-03 | 1936-06-30 | Burgess Lab Inc C F | Muffler |
US3286786A (en) * | 1964-12-23 | 1966-11-22 | Garrett Corp | Gas turbine exhaust silencer and acoustical material therefor |
US3863733A (en) * | 1972-04-03 | 1975-02-04 | Skyway Machine Inc | Exhaust silencer for internal combustion engine |
US4239091A (en) * | 1977-09-16 | 1980-12-16 | Negrao Paulo M | Muffler |
US4336863A (en) * | 1980-12-05 | 1982-06-29 | Ngk Insulators, Ltd. | Silencer in gas flow passage |
US4523662A (en) * | 1981-11-05 | 1985-06-18 | Mitsubishi Denki Kabushiki Kaisha | Muffler for exhaust gas from an internal combustion engine |
US4834214A (en) * | 1987-06-08 | 1989-05-30 | Feuling James J | Muffler for an internal combustion engine |
US5371331A (en) * | 1993-06-25 | 1994-12-06 | Wall; Alan T. | Modular muffler for motor vehicles |
US5633482A (en) * | 1995-10-10 | 1997-05-27 | Two Brothers Racing, Inc. | Motorcycle exhaust system |
US5992560A (en) * | 1996-02-21 | 1999-11-30 | Ibiden Co., Ltd. | Muffler for internal combustion engine |
US6385967B1 (en) * | 2000-05-31 | 2002-05-14 | Shun-Lai Chen | Exhaust pipe for motor vehicle muffler |
US20030213643A1 (en) * | 2002-04-05 | 2003-11-20 | Martin Hirschorn | Attenuating power booster |
US7159692B1 (en) * | 1999-10-11 | 2007-01-09 | Silentor Holding A/S | Silencer |
US7281605B2 (en) * | 2003-05-02 | 2007-10-16 | Owens-Corning Fiberglas Technology Ii, Llc | Mufflers with enhanced acoustic performance at low and moderate frequencies |
US20080185218A1 (en) * | 2005-03-24 | 2008-08-07 | Toshiyuki Kondo | Noise Eliminator For Fuel Cell |
US7510050B2 (en) * | 2004-01-27 | 2009-03-31 | Emler Don R | Vehicle exhaust systems |
Family Cites Families (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS53139037A (en) * | 1977-05-10 | 1978-12-05 | Kubota Ltd | Exhaust device |
JPS57119119A (en) * | 1981-01-15 | 1982-07-24 | Kanebo Ltd | Silencer for internal combustion engine |
JPS5945213U (en) * | 1982-09-17 | 1984-03-26 | カルソニックカンセイ株式会社 | Sound absorbing silencer |
JPH0557308U (en) * | 1992-01-10 | 1993-07-30 | 株式会社ユーメックス | Exhaust pipe structure of engine silencer |
JP2001159306A (en) * | 1999-12-02 | 2001-06-12 | Global Patent Network:Kk | Internal combustion engine |
JP2002195020A (en) * | 2000-12-22 | 2002-07-10 | Puroto:Kk | Muffler |
JP2005069191A (en) * | 2003-08-27 | 2005-03-17 | Calsonic Kansei Corp | Exhaust device |
JP2005069190A (en) * | 2003-08-27 | 2005-03-17 | Calsonic Kansei Corp | Exhaust device for fuel cell automobile |
-
2005
- 2005-06-24 JP JP2005185371A patent/JP2007005178A/en not_active Withdrawn
-
2006
- 2006-06-21 DE DE112006001389T patent/DE112006001389T5/en not_active Withdrawn
- 2006-06-21 WO PCT/JP2006/312841 patent/WO2006137570A1/en active Application Filing
- 2006-06-21 CN CNB2006800148661A patent/CN100549371C/en not_active Expired - Fee Related
- 2006-06-21 US US11/920,432 patent/US20090045006A1/en not_active Abandoned
Patent Citations (19)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1844106A (en) * | 1929-05-08 | 1932-02-09 | Burgess Lab Inc C F | Exhaust muffler |
US1912544A (en) * | 1929-11-02 | 1933-06-06 | Burgess Lab Inc C F | Method for tightly packing materials and product formed thereby |
US1921468A (en) * | 1929-11-08 | 1933-08-08 | Burgess Lab Inc C F | Muffler |
US2046193A (en) * | 1931-01-03 | 1936-06-30 | Burgess Lab Inc C F | Muffler |
US3286786A (en) * | 1964-12-23 | 1966-11-22 | Garrett Corp | Gas turbine exhaust silencer and acoustical material therefor |
US3863733A (en) * | 1972-04-03 | 1975-02-04 | Skyway Machine Inc | Exhaust silencer for internal combustion engine |
US4239091A (en) * | 1977-09-16 | 1980-12-16 | Negrao Paulo M | Muffler |
US4336863A (en) * | 1980-12-05 | 1982-06-29 | Ngk Insulators, Ltd. | Silencer in gas flow passage |
US4523662A (en) * | 1981-11-05 | 1985-06-18 | Mitsubishi Denki Kabushiki Kaisha | Muffler for exhaust gas from an internal combustion engine |
US4834214A (en) * | 1987-06-08 | 1989-05-30 | Feuling James J | Muffler for an internal combustion engine |
US5371331A (en) * | 1993-06-25 | 1994-12-06 | Wall; Alan T. | Modular muffler for motor vehicles |
US5633482A (en) * | 1995-10-10 | 1997-05-27 | Two Brothers Racing, Inc. | Motorcycle exhaust system |
US5992560A (en) * | 1996-02-21 | 1999-11-30 | Ibiden Co., Ltd. | Muffler for internal combustion engine |
US7159692B1 (en) * | 1999-10-11 | 2007-01-09 | Silentor Holding A/S | Silencer |
US6385967B1 (en) * | 2000-05-31 | 2002-05-14 | Shun-Lai Chen | Exhaust pipe for motor vehicle muffler |
US20030213643A1 (en) * | 2002-04-05 | 2003-11-20 | Martin Hirschorn | Attenuating power booster |
US7281605B2 (en) * | 2003-05-02 | 2007-10-16 | Owens-Corning Fiberglas Technology Ii, Llc | Mufflers with enhanced acoustic performance at low and moderate frequencies |
US7510050B2 (en) * | 2004-01-27 | 2009-03-31 | Emler Don R | Vehicle exhaust systems |
US20080185218A1 (en) * | 2005-03-24 | 2008-08-07 | Toshiyuki Kondo | Noise Eliminator For Fuel Cell |
Cited By (27)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7878298B2 (en) * | 2006-12-18 | 2011-02-01 | GM Global Technology Operations LLC | Fuel-cell exhaust system |
US20080141667A1 (en) * | 2006-12-18 | 2008-06-19 | Gm Global Technology Operations, Inc. | Fuel-cell exhaust system |
US20090078498A1 (en) * | 2007-09-26 | 2009-03-26 | Darrin Woods | Seamless in-line airboat muffler |
CN101907009A (en) * | 2010-07-19 | 2010-12-08 | 中国人民解放军重庆通信学院 | Impedance composite water-cooled muffler for diesel generator set |
US20160197362A1 (en) * | 2013-09-20 | 2016-07-07 | Bayerische Motoren Werke Aktiengesellschaft | Exhaust Gas System and Motor Vehicle Having an Exhaust Gas System |
US10205181B2 (en) * | 2013-09-20 | 2019-02-12 | Bayerische Motoren Werke Aktiengesellschaft | Exhaust gas system and motor vehicle having an exhaust gas system |
US10933210B2 (en) * | 2013-09-23 | 2021-03-02 | Fisher & Paykel Healthcare Limited | Nasal cannula with turbulation elements |
US20160220775A1 (en) * | 2013-09-23 | 2016-08-04 | Fisher & Paykel Healthcare Limited | Nasal cannula with turbulation elements |
CN104074585A (en) * | 2014-07-04 | 2014-10-01 | 重庆长安汽车股份有限公司 | Silencer drainage structure |
WO2016087852A1 (en) * | 2014-12-03 | 2016-06-09 | Intelligent Energy Limited | Exhaust assembly |
US10530000B2 (en) | 2014-12-03 | 2020-01-07 | Intelligent Energy Limited | Exhaust assembly |
US10233814B2 (en) | 2015-08-10 | 2019-03-19 | Faurecia Emissions Control Technologies, Germany Gmbh | Component of an exhaust system |
US20180073412A1 (en) * | 2016-09-12 | 2018-03-15 | Volvo Car Corporation | Combined heat exchanger and exhaust silencer |
US10508580B2 (en) * | 2016-09-12 | 2019-12-17 | Volvo Car Corporation | Combined heat exchanger and exhaust silencer |
US10243227B2 (en) * | 2016-12-06 | 2019-03-26 | Hyundai Motor Company | Apparatus for reducing hydrogen concentration in exhaust gas of an exhaust system for a fuel cell vehicle |
CN107636315A (en) * | 2017-03-28 | 2018-01-26 | 美的集团股份有限公司 | Pedestal and bladeless fan |
GB2572644A (en) * | 2018-04-06 | 2019-10-09 | Jaguar Land Rover Ltd | An attenuator for a fluid duct |
GB2572644B (en) * | 2018-04-06 | 2020-11-18 | Jaguar Land Rover Ltd | An attenuator having a perforated fluid duct surrounded by an enclosure |
WO2021016160A1 (en) * | 2019-07-23 | 2021-01-28 | Tenneco Automotive Operating Company Inc. | Vehicle exhaust system |
US11225897B2 (en) | 2019-07-23 | 2022-01-18 | Tenneco Automotive Operating Company Inc. | Vehicle exhaust system |
US11614009B2 (en) | 2019-07-23 | 2023-03-28 | Tenneco Automotive Operating Company Inc. | Vehicle exhaust system |
US20210239017A1 (en) * | 2020-02-03 | 2021-08-05 | Faurecia Emissions Control Technologies, Usa, Llc | Exhaust system component |
US11603781B2 (en) * | 2020-02-03 | 2023-03-14 | Faurecia Emissions Control Technologies, Usa, Llc | Exhaust system component |
CN112683539A (en) * | 2020-12-15 | 2021-04-20 | 中航工程集成设备有限公司 | Exhaust metal runner structure for aircraft engine test |
EP4102600A1 (en) * | 2021-06-10 | 2022-12-14 | NOVARES France | Exhaust silencer for a fuel cell |
FR3123944A1 (en) * | 2021-06-10 | 2022-12-16 | Novares France | Exhaust silencer for a fuel cell |
EP4290058A1 (en) * | 2022-06-09 | 2023-12-13 | Purem GmbH | Silencer |
Also Published As
Publication number | Publication date |
---|---|
WO2006137570A1 (en) | 2006-12-28 |
JP2007005178A (en) | 2007-01-11 |
DE112006001389T5 (en) | 2008-04-10 |
CN100549371C (en) | 2009-10-14 |
CN101171406A (en) | 2008-04-30 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US20090045006A1 (en) | Noise Eliminator for Fuel Cell | |
JP2007005178A5 (en) | ||
US20070125594A1 (en) | Muffler assembly with sound absorbing member | |
WO2008059707A1 (en) | Hollow fiber membrane module and fuel cell system | |
JP2009062972A (en) | Silencer | |
KR20140027394A (en) | Device for damping of sounds and motor vehicle comprising such a device | |
CA2371112A1 (en) | Muffler with acoustic absorption insert for limited clearance pneumatic device applications | |
JP2015150991A (en) | engine hood | |
JP2006344476A (en) | Exhaust gas dilution device of fuel cell | |
KR101464658B1 (en) | Silencer for fuel cell vehicle | |
JP4800690B2 (en) | Fuel cell exhaust gas treatment device | |
KR100925938B1 (en) | Exhaust gas radiation noise decreasing typed exhaust system in vehicle | |
KR20200117396A (en) | Exhaust Fluid Collision Detachable Type Muffler | |
JP6169035B2 (en) | Silencer structure for exhaust noise of fuel cell vehicles | |
JP4567851B2 (en) | silencer | |
JP2002206413A (en) | Noise eliminator | |
KR20100131202A (en) | Acoustic duct for aircleaner | |
JP4291648B2 (en) | Exhaust device for fuel cell vehicle | |
JP2021021343A (en) | Intake device of engine | |
JP2020118145A (en) | Muffler | |
KR20130033726A (en) | Complex noise decreasing type muffler | |
KR102484677B1 (en) | Muffler for fuel cell vehicles | |
RU2241126C1 (en) | Internal combustion engine muffler | |
JP2009174346A (en) | Muffler for fuel cell vehicle | |
JP2023102691A (en) | Exhaust gas purification device |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: TOYOTA JIDOSHA KABUSHIKI KAISHA, JAPAN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:KONDO, TOSHIYUKI;YANAGIHARA, KAZUNORI;TANIGUCHI, HIDEAKI;AND OTHERS;REEL/FRAME:020167/0908 Effective date: 20070823 |
|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |