JP2000341977A - Waste heat power generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance power generating capacity by providing a flange part adhering to the outer circumference of an exhaust gas channel pipe on the high temperature end face. SOLUTION: A flange part 13 adhering to the outer circumference of a heat collecting plane 3a is provided at the circumferential fringe part on the high temperature end face 9a-1 of a heat conversion module 9-1 and a flange part 15 adhering to the outer circumference of a radiating section 1a-1 is provided at the circumferential fringe part on the low temperature end face 9b-1. Consequently, the contact areas of the high temperature end face 9a-1 and the low temperature end face 9b-1 with the heat collecting plane 3a and the radiating section 1a-1 are increased as compared with the cross-sectional area of a body section 9-1a. The high temperature end face 9a-1 can thereby be heated with the waste heat of exhaust gas and the low temperature end face 9b-1 can be cooled furthermore by radiating heat by means of a fan 5, or the like. Since the effect of contact resistance is decreased, a significant gradient of heat is generated between the high temperature end face 9a-1 and the low temperature end face 9b-1 and power generating capacity of a waste heat power generator 11-1 can be enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exhaust heat power generator for recovering exhaust heat of exhaust gas discharged from an automobile engine or the like and converting it into electric power.

[0002]

2. Description of the Related Art Conventionally, as disclosed in Japanese Patent Application Laid-Open No. Hei 10-234194, an exhaust heat power generation system that recovers exhaust heat of exhaust gas discharged from an automobile engine or a furnace of a factory and converts it into electric power. The device is widely known. FIG. 5 shows a waste heat power generator disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 10-234194. In the figure, reference numeral 1 denotes a pair of half-split outer cylinders 1a and 1b formed of aluminum in a substantially U-shaped cross section. The outer cylinder 3 is a flat stainless steel inner cylinder housed in the outer cylinder 1 with a predetermined gap therebetween, and the inner cylinder 3 is an exhaust pipe of a vehicle exhaust system via a diffuser (not shown). And the heat radiation surfaces 1a-1 and 1b of the half-split outer cylinders 1a and 1b.
At -1, a large number of radiating fins 5, 7 protrude outward along the traveling direction of the automobile.

The heat radiation surfaces 1a-1 and 1a-1 of the outer cylinders 1a and 1b
A plurality of cubic thermoelectric conversion modules 9 are mounted between 1b-1 and the heat collecting surfaces 3a and 3b of the inner cylinder 3 opposed thereto. In the thermoelectric conversion module 9, a plurality of thermoelectric element pairs composed of a p-type semiconductor and an n-type semiconductor are thermally connected in parallel and electrically connected in series via electrodes formed at both ends of the element pair. An electrode is formed on a high-temperature end face 9a of the ceramic thermoelectric element assembly, and
An output terminal for extracting generated power is attached to the low-temperature end face 9b.

The thermoelectric conversion module 9 has a structure in which the high-temperature end surface 9a contacts the heat collecting surfaces 3a and 3b of the inner cylinder 3 and the low-temperature end surface 9b contacts the heat radiation surfaces 1a and 1b of the outer cylinder 1. The exhaust heat of the exhaust gas flowing down in the inner cylinder 3 is transmitted from the heat collecting surfaces 3a and 3b to the high temperature end surface 9a of the thermoelectric conversion module 9, and the high temperature end surface 9a is heated.

At the same time, the thermoelectric conversion module 9
Of the low-temperature end face 9b of the outer cylinder 1
The low-temperature end face 9b is cooled by radiating heat by the radiating fins 5, 7 provided on the thermoelectric conversion module 9. The thermoelectric conversion module according to the heat gradient generated between the high-temperature end face 9a and the low-temperature end face 9b of the thermoelectric conversion module 9. 9, a thermoelectromotive force is generated to generate power.

[0006]

However, the exhaust heat power generation device 11 has a high temperature end face 9a of the thermoelectric conversion module 9.
And heat collecting surfaces 3a and 3b of the inner cylinder 3 and the thermoelectric conversion module 9
The low-temperature end face 9b of the thermoelectric conversion module 9 has a large contact thermal resistance due to insufficient bonding between the low-temperature end face 9b and the heat radiating surfaces 1a and 1b of the outer cylinder 1. It is pointed out that there is no thermal gradient between them and that the power generation capacity is low.

The present invention has been devised in view of the above circumstances, and has as its object to provide a waste heat power generator with improved power generation capacity.

[0008]

Means for Solving the Problems To achieve the above object, the invention according to claim 1 is directed to an exhaust heat power generator in which a high-temperature end face of a thermoelectric conversion module is brought into contact with an exhaust gas flow pipe.
The high-temperature end face is provided with a flange portion that is in close contact with the outer periphery of the exhaust gas flow tube, and the invention according to claim 2 is characterized in that:
In the exhaust heat power generator in which the high-temperature end face of the thermoelectric conversion module is brought into contact with the exhaust gas flow pipe, the high-temperature end face has a non-planar shape, and the outer circumference of the exhaust gas flow pipe corresponds to the shape of the high-temperature end face. The mounting portion is provided.

According to a third aspect of the present invention, there is provided an exhaust heat power generator in which a high-temperature end face of a thermoelectric conversion module is brought into contact with an exhaust gas flow pipe. The invention according to claim 4 is characterized in that it is fixed to the outer circumference of the pipe or that the high-temperature end face is fixed to the outer circumference of the exhaust gas flow pipe by subjecting ceramics to a metal coating treatment. In the exhaust heat power generator according to any one of the above, a heat collecting surface is formed on at least one surface,
A flat inner cylinder into which exhaust gas flows from an exhaust pipe, and the inner cylinder are housed at an interval inside, and a radiation fin is formed outside a heat radiation surface facing a heat collection surface of the inner cylinder. A flat outer cylinder and a thermoelectric conversion module mounted between the heat collecting surface of the inner cylinder and the heat radiating surface of the outer cylinder, with the high-temperature end face in contact with the heat collecting face and the low-temperature end face in contact with the heat radiating face. It is characterized by being provided.

(Action) According to the exhaust heat power generator according to claims 1 to 3, the exhaust heat of the exhaust gas flowing down in the exhaust gas passage pipe heats the high-temperature end face of the thermoelectric conversion module. According to the invention of claim 4, the high-temperature exhaust gas flowing down in the inner cylinder heats the high-temperature end face of the thermoelectric conversion module. At the same time, the heat of the low-temperature end face of the thermoelectric conversion module is provided to the outer cylinder. The low-temperature end face is cooled by being radiated by the radiating fins, and a thermoelectromotive force is generated in the thermoelectric conversion module according to a heat gradient generated between the high and low-temperature end faces to generate power. 1, Claim 2 and Claim 4
According to the present invention, the contact area of the high-temperature end face is increased from the low-temperature end face as compared with the conventional art, so that a large thermal gradient is generated between the high- and low-temperature end faces as compared with the conventional art, and a thermoelectromotive force is generated in the thermoelectric conversion module. I do.

[0011] Similarly, according to the third and fourth aspects of the present invention, a large thermal gradient is generated between the high and low temperature end faces as compared with the prior art, and a thermoelectromotive force is generated in the thermoelectric conversion module. Become.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. Since the configuration except for the invention is the same as that of the conventional example shown in FIG. 5, the same components are denoted by the same reference numerals and description thereof will be omitted.

FIG. 1 is an enlarged sectional view of a main part of an exhaust heat power generator according to an embodiment of the present invention.
-1 is a thermoelectric conversion module mounted between the heat radiating surfaces 1a-1 and 1b-1 of the outer cylinder 1 and the heat collecting surfaces 3a and 3b of the inner cylinder 3 opposed thereto. Is the main unit 9-1
a is formed in a rectangular cross section and has the same internal structure as that of the thermoelectric conversion module 9 in FIG. 5, and the high-temperature end face 9a-1 on which the electrodes are formed is in close contact with the heat collecting faces 3a and 3b. ,
Low-temperature end face 9b-1 to which an output terminal for extracting generated power is attached
Are closely attached to the heat radiation surfaces 1a-1 and 1b-1 of the outer cylinder 1.

As shown in the figure, in the present embodiment, a flange 13 is provided on the periphery of the high-temperature end face 9a-1 of the thermoelectric conversion module 9-1 so as to be in close contact with the outer periphery of the heat collecting surfaces 3a and 3b. A flange portion 15 which is in close contact with the outer periphery of the surfaces 1a-1 and 1b-1 is provided on the periphery of the low-temperature end surface 9b-1 to provide a high-temperature end surface 9a- with respect to the heat collecting surfaces 3a and 3b and the heat radiation surfaces 1a-1 and 1b-1. 1. The contact area of the low-temperature end face 9b-1 is larger than the cross-sectional area of the main body 9-1a.

The exhaust heat power generator 11-1 according to the present embodiment is configured as described above, and the exhaust heat of the exhaust gas flowing down in the inner cylinder 3 is transferred from the heat collecting surfaces 3a and 3b to the thermoelectric conversion module 9-1. The heat is transmitted to the high-temperature end face 9a-1 to heat the high-temperature end face 9a-1, and at the same time, the heat of the low-temperature end face 9b-1 of the thermoelectric conversion module 9-1 is transferred to the heat radiation faces 1a-1 and 1b-1. The radiating fins 5 and 7 dissipate heat to cool the low-temperature end face 9b-1 and apply heat to the thermoelectric conversion module 9-1 according to the heat gradient generated between the high and low-temperature end faces 9a-1 and 9b-1. Although an electromotive force is generated and power is generated, as described above, in the present embodiment, the hot end face 9a-1 and the cold end face 9b-1 are smaller than the main body 9-1a of the thermoelectric conversion module 9-1. Since the contact area is increased, the high-temperature end face 9a-1 is further heated by the exhaust heat of the exhaust gas as compared with the conventional example shown in FIG. The warm end face 9b-1 is radiated by the radiating fins 5, 7 and is further cooled.

Therefore, according to the present embodiment, the influence of the contact thermal resistance is smaller than in the conventional example, and a large thermal gradient is generated between the high-temperature end face 9a-1 and the low-temperature end face 9b-1. The power generation capacity is improved as compared with the waste heat power generation device 11 described above.

In this embodiment, the high and low temperature end faces 9a-1,
Although the flanges 13 and 15 are provided on the periphery of 9b-1 respectively, the flange 13 may be provided only on the high-temperature end face 9a-1 side, and even with such a structure, the high-temperature end face 9a-1 and the low-temperature end face 9b are provided. Since a large thermal gradient is generated between the exhaust heat power generation device 11 and the conventional exhaust heat power generation device 11, the power generation capacity is improved.
FIG. 2 is an enlarged cross-sectional view of a main part of the exhaust heat power generation device according to the first embodiment of claims 2 and 4, wherein 3-1 is the same as the inner cylinder 3 already described in FIG. A flat stainless steel inner cylinder housed in the cylinder 1 with a predetermined gap therebetween.
Also connected to the exhaust pipe of the vehicle exhaust system via a diffuser (not shown), a heat collecting surface 3a-1 is formed facing the heat radiating surface 1a-1 of the outer cylinder 1, and the heat radiating surface of the outer cylinder 1 is formed. A heat collecting surface 3b-1 (not shown) is formed opposite to 1b-1.

A thermoelectric conversion module shown in FIG. 5 is provided between the heat radiating surfaces 1a-1 and 1b-1 of the outer cylinder 1 and the heat collecting surfaces 3a-1 and 3b-1 of the inner cylinder 3-1 opposed thereto. A plurality of thermoelectric conversion modules 9-2 having the same internal structure as 9 are arranged,
In each thermoelectric conversion module 9-2, a main body 9-2a is formed in a rectangular cross section, an electrode is formed on a high-temperature end face 9a-2, and an output terminal for extracting generated power is provided on a low-temperature end face 9b-2. Installed.

In the thermoelectric conversion module 9-2, the high-temperature end face 9a-2 is in close contact with the heat collecting faces 3a-1 and 3b-1 of the inner cylinder 3-1 and the low-temperature end face 9b-2 is outside. The heat radiation surface 1a-1 of the cylinder 1,
Although the structure is in close contact with the low-temperature end face 9b-2 formed along the inner surfaces of the heat-radiating surfaces 1a-1 and 1b-1 as shown in FIG. End face 9a
-2 is formed into a tapered cross-section with a protruding center, and heat collecting surface 3
The contact area of the high-temperature end face 9a-2 with respect to the a-1 and 3b-1 is made larger than the contact area of the low-temperature end face 9b-2 with the heat radiation surfaces 1a-1 and 1b-1, and corresponds to the shape of the hot end face 9a-2. The mounting concave portion 17 having a tapered cross section is formed as the heat collecting surface 3a-1,
3b-1, and the high-temperature end face 9a-2 is
7 and is in close contact with the heat collecting surfaces 3a-1 and 3b-1.

The exhaust heat power generation device 11-2 according to the present embodiment is configured as described above.
Exhaust heat of the exhaust gas flowing down inside -1 is transmitted from the heat collecting surfaces 3a-1 and 3b-1 to the high-temperature end surface 9a-2 of the thermoelectric conversion module 9-2 to heat the high-temperature end surface 9a-2, At the same time, the heat of the low-temperature end face 9b-2 is radiated by the radiating fins 5, 7, and the low-temperature end face 9b-1 is cooled.
A thermoelectromotive force is generated in the thermoelectric conversion module 9-2 in accordance with the thermal gradient generated between 2, 9b-2, and power is generated.
As described above, in the present embodiment, since the contact area of the high-temperature end face 9a-2 is larger than the contact area of the low-temperature end face 9b-2, a large heat is generated between the high-temperature end face 9a-2 and the low-temperature end face 9b-2. A gradient is generated, and the power generation capacity is improved as compared with the conventional exhaust heat power generation device 11.

FIG. 3 is an enlarged sectional view of a main part of a waste heat power generator according to a second embodiment of the present invention.
Reference numeral 3-2 denotes a flat stainless steel inner cylinder which is accommodated in the outer cylinder 1 with a predetermined gap therebetween, similarly to the inner cylinder 3-1. Although not shown, the inner cylinder 3-1 is also connected via a diffuser. It is connected to the exhaust pipe of the vehicle exhaust system, and a heat collecting surface 3a-2 is formed facing the heat radiating surface 1a-1 of the outer cylinder 1.
A heat collecting surface 3b-2 (not shown) is formed opposite to b-1.

The thermoelectric conversion module 9- is disposed between the heat radiation surfaces 1a-1 and 1b-1 of the outer cylinder 1 and the heat collection surfaces 3a-2 and 3b-2 of the inner cylinder 3-2 opposed thereto. Although a plurality of thermoelectric conversion modules 9-3 having the same internal structure as in FIG. 2 are arranged, as shown in FIG.
The low-temperature end face 9b-3, which is in close contact with the inner surface of -1 and the high-temperature end face 9a-3, which is in close contact with the heat-collecting faces 3a-2, 3b-2, is formed into a saw-tooth cross-section. The contact area of the high-temperature end surface 9a-3 with respect to the heat-radiating surfaces 1a-1 and 1b-1 is made larger than the contact area of the low-temperature end surface 9b-3 with the heat-radiating surfaces 1a-1 and 1b-1, and the heat collecting surfaces 3a-2 and 3b. -2, a mounting concave portion 19 having a sawtooth cross section corresponding to the shape of the high-temperature end surface 9a-3 is formed. The high-temperature end surface 9a-3 is fitted into the concave portion 19 to form a heat collecting surface 3a-21, 3b-2.

The exhaust heat power generation device 11-3 according to the present embodiment is configured as described above, and like the embodiment shown in FIG.
Since a large thermal gradient is generated between the high-temperature end face 9a-3 and the low-temperature end face 9b-3 as compared with the conventional case, there is an advantage that the power generation capacity is improved. FIG. 4 is an enlarged cross-sectional view of a main part of a waste heat power generation device according to an embodiment of claims 3 and 4.
Heat radiating surfaces 1a-1 and 1b-1 of outer cylinder 1 and inner cylinder 3 opposed thereto
In mounting the plurality of thermoelectric conversion modules 9 between the heat collecting surfaces 3a and 3b, the high-temperature end surface 9a of the thermoelectric conversion module 9 is fixed to the outer periphery of the heat collecting surface 3a of the inner cylinder 3 by using a ceramic adhesive 21. And the low-temperature end face 9b is radiated to the heat radiating surface 1a of the outer cylinder 1 through the silicon-based gasket 23.
-1 and 1b-1.

Thus, according to the present embodiment, the high-temperature end face 9
Since a is bonded to the heat collecting surfaces 3a and 3b by the adhesive 21, the contact thermal resistance is smaller than that of the conventional example shown in FIG. Further, since the low-temperature end face 9b is fixed to the heat radiating surfaces 1a-1 and 1b-1 of the outer cylinder 1 via the gasket 23, the contact heat resistance is smaller than in the conventional case, and the deformation due to the temperature change is prevented. 23 always absorbs the hot end face 9a.
And the low-temperature end face 9b is the heat collecting faces 3a and 3b and the heat radiating faces 1a-1 and 1a.
While being pressed against b-1, the thermoelectric conversion module 9 is prevented from being damaged by the deformation and absorption of the gasket 23.

Therefore, the exhaust heat power generator 1 according to the present embodiment
1-4 also causes a large thermal gradient between the high-temperature end face 9a and the low-temperature end face 9b.
The power generation capacity was improved compared to 1. As described above, in the present embodiment, the high-temperature end face 9a of the thermoelectric conversion module 9 is bonded to the heat-collecting face 3a of the inner cylinder 3 using the ceramic adhesive 21.
May be subjected to ceramic and metal coating treatment (metal plating with gold or silver) to be pressed and fixed to the heat collecting surface 3a,
According to such an embodiment, the intended purpose can be achieved similarly to the embodiment shown in FIG.

In each of the above embodiments, the exhaust heat power generation device according to the present invention is mounted on a vehicle exhaust system. However, the present invention is not limited to such an embodiment, and the present invention is not limited to a plant furnace. It is also possible to generate power by recovering the exhaust heat of the discharged exhaust gas.

[0027]

As described above, according to the exhaust heat power generator according to each of the claims, heat conduction loss to the thermoelectric conversion module does not occur as compared with the prior art, and therefore, the thermoelectric conversion module as compared with the prior art A large thermal gradient was generated between the high-temperature end face and the low-temperature end face of the module, and the power generation capacity was improved.

[Brief description of the drawings]

FIG. 1 is an enlarged sectional view of a main part of a waste heat power generation device according to an embodiment of the present invention.

FIG. 2 is an enlarged sectional view of a main part of the exhaust heat power generation device according to the first embodiment of claims 2 and 4.

FIG. 3 is an enlarged sectional view of a main part of a waste heat power generation device according to a second embodiment of the present invention.

FIG. 4 is an enlarged cross-sectional view of a main part of a waste heat power generation device according to an embodiment of the present invention.

FIG. 5 is a sectional view of a conventional exhaust heat power generator.

[Explanation of symbols]

 1 outer cylinder 1a-1 heat radiation surface 3,3-1,3-2 inner cylinder 3a, 3a-1,3a-2 heat collection surface 5,7 radiation fin 9,9-1,9-2,9-3 thermoelectric Conversion module 9a, 9a-1, 9a-2, 9a-3 High-temperature end face 9b, 9b-1, 9b-2, 9b-3 Low-temperature end face 11-1, 11-2, 11-3, 11-4 Waste heat generation Apparatus 13,15 Flange 17,17 Recess 21 Adhesive 23 Gasket

Claims (4)

[Claims] 1. A thermoelectric conversion module (9)
In the exhaust heat power generation device (11-1) in which the high temperature end face (9a-1) is brought into contact with the high temperature end face (9a-1), the flange portion which is in close contact with the outer periphery of the exhaust gas flow pipe is provided. (13) An exhaust heat power generator provided with (13). 2. A thermoelectric conversion module (9)
-2, 9-3), the high-temperature end faces (9a-2, 9-3) are brought into contact with the exhaust heat power generators (11-2, 11-3). -3) has a non-planar shape, and the high-temperature end faces (9a-2, 9a)
(3) An exhaust heat power generation device comprising a mounting portion (17, 19) corresponding to the shape of (3). 3. A waste heat power generator (11-4) in which a high-temperature end face (9a) of a thermoelectric conversion module (9) is brought into contact with an exhaust gas flow pipe, wherein the high-temperature end face (9a) is ceramic-based bonded. Agent (21)
A waste heat power generator characterized by being fixed to the outer periphery of an exhaust gas flow tube via a ceramic or a metal coating treatment on a high-temperature end surface (9a) of the ceramics. 4. A heat collecting surface (3a, 3a-)
1, 3a-2) formed therein, and a flat inner cylinder (3,3-1,3-2) into which exhaust gas flows from an exhaust pipe, and the inner cylinder (3,3-1,3-2) inside. 3-2) are accommodated at intervals, and the heat collecting surfaces (3a, 3a-) of the inner cylinder (3, 3-1, 3-2) are accommodated.
A flat outer cylinder (1) having a heat radiation fin (5) formed on the outside of a heat radiation surface (1a-1) opposed to a first heat exchanger (1, 3a-2); ) Heat collecting surface (3a, 3a-1, 3a)
-2) and the heat radiating surface (1a-1) of the outer cylinder (1), and the high-temperature end surfaces (9a, 9a-1, 9a-2, 9a-3) are heat collecting surfaces (3a, 3a-). 1, 3a-2) and the low-temperature end face (9b,
9b-1, 9b-2, 9b-3) with thermoelectric conversion modules (9, 9-1, 9-2, 9-3) in contact with the heat radiating surface (1a-1). The exhaust heat power generator according to any one of claims 1 to 3, wherein