The present invention relates to an engine system. More specifically, the present invention relates to an engine system which employs as a fuel, either hydrogen produced from a hydrogen containing medium in terms of reaction using a catalyst or mixture of the hydrogen and the hydrogen containing medium.
Since the engine system which employs gasoline as a fuel discharges carbon dioxide, hydrogen has been gaining attention as an alternative fuel for the countermeasure to global warming. However, usage of hydrogen is difficult in that hydrogen is combustible material and is highly explosive. Particularly, a high technique must be required for storing hydrogen in a gas state or a liquid state, and it is also a difficult technique to store hydrogen so from the viewpoint of safety and a large weight of a storage container.
Therefore, a technique has been developed in which hydrogen is stored while being contained in a hydrogen medium, hydrogen gas is extracted in terms of a chemical reaction at a necessary time, and then the hydrogen gas is supplied to the engine system. However, it is necessary to provide a constant heat source all the time when proceeding chemical reaction due to the fact that the chemical reaction takes place as an endothermic reaction. For example, in an automobile mounting thereon the engine system employing the gasoline as a fuel, when the afore-mentioned engine supplied with the hydrogen gas in terms of the chemical reaction, is mounted to replace the gasoline engine, a certain technique has been proposed in which the exhaust gas from the engine is used as the heat source (see JP-A-2005-299499).
Such a reactor incorporated in this type of engine system is operated under a high-temperature circumstance due to the exhaust gas from the engine. In some cases, a problem may arise in that the reactor itself is subjected to a thermal deformation due to different heat expansions of the respective parts of the reactor caused by either a combination of materials having different linear expansion coefficients or a difference in local temperature of the reactor. In case of severe deformation, since respective sectional areas of a plurality of fuel flow passageways or exhaust gas flow passage become non-uniform, heat amount supplied from the exhaust gas becomes non-uniform, thereby causing such a problem that reaction efficiency of the reactor is deteriorated as a whole.
Although there is disclosed a technique of a heat exchanger provided with a heat transfer mechanism which is the same as that of the reactor in various industrial fields, the technique is not based on the particular circumstance as mounted on the above-described automobile. For this reason, in spite of the fact that the engine system needs to be compact in size, it is difficult to avoid an increase in size or a complication of the engine system.
An object of the invention is to provide an engine system which is able to reduce an influence due to heat deformation of a reactor and in which either hydrogen produced from a hydrogen containing medium in terms of reaction using a catalyst or a mixture of the hydrogen and the hydrogen containing medium is employed as a fuel.
In order to achieve the above-described object, according to an aspect of the invention, there is provided an engine system in which either hydrogen produced from a hydrogen containing medium in terms of reaction using a catalyst or a mixture of the hydrogen and the hydrogen containing medium is employed as fuel, the engine system including a reactor configured to cause a reaction using the catalyst, wherein the reactor is configured by alternately disposing a plurality exhaust passageways and a plurality of fuel passageways of the engine system with a wall interposed therebetween, wherein at least one carrier configured to carry the catalyst and to be formed in a substantially rectangular plate shape is interposed in the inside of at least one of fuel passageways, and wherein the carrier is provided with a plate portion which has a surface disposed in a fuel flowing direction and is formed in a substantially rectangular plate shape, and at least one slit portion which divides the surface of the plate portion in a fuel flowing direction.
According to the above-described configuration of the invention, in the engine system in which either hydrogen produced from a hydrogen containing medium in terms of reaction using a catalyst or a mixture of the hydrogen and the hydrogen containing medium is employed as a fuel, since the slit is formed in the carrier of the reactor so as to reduce a variation in heat transmission circumstance in the inside of the reactor, it is possible to reduce an influence of heat deformation on the reactor.
According to the engine system, since it is possible to reduce the influence of the heat deformation of the reactor, it is possible to restrict deterioration of reaction efficiency of the reactor as a whole.
Other objects, features and advantages of the invention will become apparent from the following description of the embodiments of the invention taken in conjunction with the accompanying drawings.
Embodiment 1
Hereinafter, a first embodiment of the invention will be described in detail with reference to the accompanying drawings.
An engine system 100 according to the present embodiment includes an engine 10 employing a hydrogen medium as a fuel. The engine 10 is connected to an intake pipe 11 and an exhaust pipe 12, and a reactor 1 is disposed in a portion of the exhaust pipe 12.
Here, the hydrogen medium indicates all mediums capable of chemically storing and discharging hydrogen, which includes hydrocarbon-based fuel such as gasoline, light oil, kerosene, heavy oil, decaline, cyclohexane, methyl-cyclohexane, naphthalene, benzene, and toluene, mixed fuel thereof, hydrogen peroxide, ammonia, nitrogen, or oxygen. In the below description, the medium chemically storing hydrogen is referred to as “hydrogen medium” and the medium chemically discharging hydrogen is referred to as “dehydrogenation medium”.
The hydrogen medium as a fuel is introduced from a hydrogen medium tank 14 to a pump 30 (see the arrow F01). Then, the hydrogen medium is pressurized by the pump 30, and is injected into a reactor 1 via a pipe 41 (see the arrow F02). Since the hydrogen medium contacts with a catalyst at a high temperature in the reactor 1, chemical reaction therebetween is promoted. Subsequently, the hydrogen medium is decomposed to produce reaction gas including dehydrogenation medium and hydrogen gas.
The produced gas passes through a pipe 44 (see the arrow F03) and is supplied to a separator 16. In the separator 16 provided with a cooler, the produced gas is separated into hydrogen and other dehydrogenation mediums. The separated dehydrogenation mediums pass through a pipe 45 (see the arrow F04) and are stored in a dehydrogenation medium tank 15. On the other hand, the separated hydrogen passes through a pipe 46 (see the arrow F05) and is supplied to the inside (not shown) of the engine 10 via the intake pipe 11. The hydrogen combusted in the engine 10 becomes high-temperature exhaust gas. The high-temperature exhaust gas passes through the exhaust pipe 12 (see the arrow F06), is supplied as a heat source to the reactor 1, and then is discharged to the atmosphere via the reactor 1 (see the arrow F07).
Additionally, a reaction speed of the dehydrogenation reaction increases as the temperature increases. Therefore, in the present embodiment, since the outermost flow passageway (the uppermost portion and the downmost portion shown in
As shown in
With such a configuration, even when a part of the plate is deformed by the heat influence and a part of the flow-passage section of the plate fuel passageway 62 becomes non-uniform, the plate fuel passageway 62 is capable of flowing the fuel on the upstream side and the downstream side of the non-uniform part in terms of the slit 63. In terms of the flow of the fuel, it is possible to more appropriately distribute the hydrogen medium (redistribution) and thus to make the reaction uniform.
For example, even when a part of the plate fuel passageway 62 is closed by heat deformation, since the slit 63 is provided, a flow passageway capable of avoiding the closed part exists at other parts. Accordingly, since the fuel flows into the flow passageway, it is possible to reduce a non-uniform state of the transmitted heat amount, and thus to restrict deterioration of the reaction efficiency of the reactor 1 as a whole.
Additionally, since the multiple sheets of plates 61 are fitted into the fuel passageway 51 while being superposed or laminated (see
Here, since a heat-resisting property needs to be ensured in the housing 53 and a catalyst carrying function needs to be ensured in the plate 61, in some cases, the housing 53 and the plate 61 may be formed of different metal materials. In accordance with a combination of different metal materials, the plate 61 may be largely thermal-expanded in a transverse direction (in a horizontal direction of
Since the dehydrogenation reaction is endothermic reaction, sufficient heat needs to be supplied, and hence a heat supply passageway to the reactor 1 is important. A main heat transmission route to the fuel passageway 51 is configured such that the exhaust heat of the engine is transmitted to the housing 53, is conducted to the plate 61, and then is transmitted to the plate fuel passageway 62 (fuel passageway 51). In the present embodiment, since a minimum width of the slit 63 is smaller than that of the plate fuel passageway 62, most of hydrogen medium flows through the plate fuel passageway 62.
Additionally, in the present embodiment, since the slit 63 is formed in the vicinity of the center in a transverse direction of the plate 61, heat is high-efficiently supplied from the housing 53 located in the outside in a transverse direction of
With such a configuration, since it is possible to increase the area carrying the catalyst necessary for the dehydrogenation reaction, it is possible to realize a compact in size of the reactor 1.
Embodiment 2
Next, the engine system according to a second embodiment of the invention will be described. In the engine system according to the present embodiment, the same reference numerals designate the same or like components as those of the first embodiment (see
The present embodiment is different from the first embodiment in that the shape of the plate 161 shown in
Likewise, since the left and right plates 161L and 161R are bridge-connected to each other via the connection portions 167 and 168, it is possible to reduce an influence of the heat deformation during an operation. Also, since the plates 161 are integrally formed with each other, it is possible to easily carry out the positioning operation of the plate 161 upon manufacturing the reactor 2, and thus to reduce a manufacture cost and a manufacture time.
For example, when the second connection portion 168 having a width of 0.2 mm or less is bridge-connected, elastic deformation easily occurs to thereby absorb the expansion of the plate 161.
Embodiment 3
Next, the engine system according to a third embodiment of the invention will be described. In the engine system according to the present embodiment, the same reference numerals are given to the same components as those of the first embodiment (see
In the present embodiment, protrusions 266 are formed in a second plate 265, and the other configurations are the same as those of the second embodiment. It is desirable that a height of each protrusion 266 is the same as that of the first plate 64 got higher in a stepped shape from the second plate 265 or twice higher than that of the first plate 64. In case of the same height, it is desirable that the protrusions 266 are formed in both surfaces of the second plate 265. On the other hand, in case of twice height, it is desirable that the protrusion 266 is formed in one surface.
In the adjacent laminated plates 261 and 261, a gap between the second plates 265 and 265 opposed to each other forms a fuel passageway. With such a configuration, since the protrusions 266 and 266 formed in the second plates 265 and 265 opposed to each other are brought into contact with each other or the protrusion 266 is brought into contact with the opposed second plate 265 as well as the first plates 64 combined with each other, it is possible to maintain a gap between the adjacent plates 261 and 261 by using the protrusion 266 as a support, and thus to prevent the non-uniform state of the fuel passageway.
A shape of the protrusion 266 may be a semi-spherical shape, a conical shape, or a pyramid shape, but it is desirable that the protrusion 266 is formed into a surface-contacting shape such as a cylindrical shape or a prism shape because the contact parts are easily deformed when, due to the heat deformation, the protrusion 266 is brought into contact with the adjacent laminated plates 261 or is brought into contact with the housing 53 (see
Embodiment 4
Next, the engine system according to a fourth embodiment of the invention will be described. In the engine system according to the present embodiment, the same reference numerals are given to the same components as those of the first embodiment to the third embodiment, and the repetitive description thereof will be omitted. The different parts from the first embodiment to the third embodiment will be mainly described.
In the present embodiment, a plurality of slits 363 is formed in a second plate 365. Since the plurality of slits 363 is provided, it is possible to increase the surface area of the plate 361. Since the performance of the reactor 1 is improved by increasing the contact area between the hydrogen medium and the plate 361 carrying the catalyst, it is possible to realize a compact in size of the reactor 1. Even in the present embodiment, like the second embodiment shown in
Embodiment 5
Next, the engine system according to a fifth embodiment of the invention will be described. In the engine system according to the present embodiment, the same reference numerals are given to the same components as those of the first embodiment to the fourth embodiment, and the repetitive description thereof will be omitted. The different parts from the first embodiment to the fourth embodiment will be mainly described.
In the present embodiment, a plurality of slits 463 is formed in the plate 461. The slit 463 includes a longitudinal slit 463L extending in a flow passageway direction and a transverse slit 463S extending in a direction perpendicular to the flow passageway, which are formed in two directions meeting at right angles.
Then, in the present embodiment, as shown in
Likewise, since the longitudinal slit 463L and the transverse slit 463S are provided, it is possible to reduce heat deformation in a flow passageway direction where fuel flows and a direction meeting at right angles with the flow passageway. Additionally, fluid flowing to the fuel passageway 62 (see
Embodiment 6
Next, the engine system according to a sixth embodiment of the invention will be described. In the engine system according to the present embodiment, the same reference numerals are given to the same components as those of the first embodiment to the fifth embodiment, and the repetitive description thereof will be omitted. The different parts from the first embodiment to the fifth embodiment will be mainly described.
Three laminated plates 571, 572, and 573 having the plurality of laminated plates 561 are disposed with a predetermined gap L therebetween in a fuel flowing direction. With such a configuration, it is possible to obtain the following advantages. That is, when the laminated plate 573 corresponding to a fuel entrance (see the arrow IN) is largely deformed by heat, the plate fuel passageway 62 of the fuel entrance (see the arrow IN) becomes non-uniform, thereby causing a case in which in some parts, the fuel does not contact with the medium. Even in this case, the uniform plate fuel passageway 62 is ensured in the other laminated plates 571 and 572 less influenced by heat than the laminated plate 573. Accordingly, the fuel passing through a slit 563 of the laminated plate 573 passes through the plate fuel passageway 62 of the laminated plates 571 and 572, thereby preventing deterioration of the reaction efficiency of the reactor 1.
As described above, the preferred embodiments of the invention have been described. The invention is not limited to the description of the drawings, but may be modified within a scope not departing from the spirit of the invention.
For example, the slit is formed in a linear shape, but may be formed in a curve shape or a wave shape. Additionally, the number of connection portions formed as bridge in the slit may increase. Likewise, various modifications may be made within a scope not departing from the spirit of the invention that the influence of the heat deformation reduces.
It should be further understood by those skilled in the art that although the foregoing description has been made on embodiments of the invention, the invention is not limited thereto and various changes and modifications may be made without departing from the spirit of the invention and the scope of the appended claims.
Number | Date | Country | Kind |
---|---|---|---|
2007-309664 | Nov 2007 | JP | national |
Number | Name | Date | Kind |
---|---|---|---|
3800768 | Rhodes et al. | Apr 1974 | A |
3855372 | Koch | Dec 1974 | A |
4018190 | Henault | Apr 1977 | A |
4170200 | Takeuchi et al. | Oct 1979 | A |
4862836 | Chen et al. | Sep 1989 | A |
6257175 | Mosher et al. | Jul 2001 | B1 |
6314919 | Pugachev | Nov 2001 | B1 |
6571748 | Holder et al. | Jun 2003 | B2 |
7235322 | Akikusa et al. | Jun 2007 | B2 |
7568452 | Shimada et al. | Aug 2009 | B2 |
7703445 | Haga | Apr 2010 | B2 |
20020104697 | Hatanaka | Aug 2002 | A1 |
20060051261 | Rong et al. | Mar 2006 | A1 |
20060204799 | Ishikawa et al. | Sep 2006 | A1 |
20070028905 | Shinagawa et al. | Feb 2007 | A1 |
20070151527 | Shinagawa et al. | Jul 2007 | A1 |
20070209609 | Shimada et al. | Sep 2007 | A1 |
20080141984 | Haga | Jun 2008 | A1 |
20080241615 | Sugimasa et al. | Oct 2008 | A1 |
20080245318 | Kuroki et al. | Oct 2008 | A1 |
20090090312 | Stehl et al. | Apr 2009 | A1 |
20090194042 | Workman et al. | Aug 2009 | A1 |
20100180839 | Otterstrom et al. | Jul 2010 | A1 |
20100275858 | Jeffs et al. | Nov 2010 | A1 |
20110005473 | Ishikawa et al. | Jan 2011 | A1 |
Number | Date | Country |
---|---|---|
1 691 065 | Aug 2006 | EP |
58-138252 | Aug 1983 | JP |
59 120773 | Jul 1984 | JP |
60-062646 | Apr 1985 | JP |
2002-060279 | Feb 2002 | JP |
2005-291657 | Oct 2005 | JP |
2005-299499 | Oct 2005 | JP |
2006-248814 | Sep 2006 | JP |
2008-088922 | Apr 2008 | JP |
Number | Date | Country | |
---|---|---|---|
20090139470 A1 | Jun 2009 | US |