JP5443952B2 - Thermoelectric generator - Google Patents

Description

  The present invention relates to a thermoelectric power generation apparatus that converts thermal energy into electrical energy by a temperature difference using a thermoelectric conversion element, and more particularly to a thermoelectric power generation apparatus that applies a fluid as a heat source.

In recent years, the energy consumption of mankind has accelerated unprecedentedly with the development of industry and science and technology. As a result, the problem of global warming due to greenhouse gases such as CO ₂ has emerged. In order to suppress the generation of greenhouse gases as much as possible, the high-temperature heat energy that is currently discarded from internal combustion engines such as automobiles, as well as various industries such as gas incinerators and thermal power plants, is used as much as possible. The production of power generators that recover energy is expected.

  A power generation technique using a thermoelectric power generation element is well known as a power generation apparatus that recovers thermal energy as electric energy. This thermoelectric power generation element utilizes the Seebeck effect that gives a temperature difference between both ends of a metal or a semiconductor and generates a potential difference between a high temperature part and a low temperature part. The larger the temperature difference, the larger the power generation amount. There is a feature. Usually, it is often used in the form of a thermoelectric module incorporating a plurality of thermoelectric power generation elements.

Conventionally, as a thermoelectric power generation apparatus using such a thermoelectric module, for example, for the purpose of converting exhaust heat energy of an internal combustion engine into electric energy, the thermoelectric module is brought into a pressed state by tightening with a band or the like, and the thermoelectric module Various configurations have been proposed in which a high-temperature medium flow path and a low-temperature medium flow path are brought into contact with a high-temperature surface and a low-temperature surface, respectively, and heat energy is converted into electric energy (see, for example, Patent Document 1). .

JP 2007-6619 A

In the conventionally proposed thermoelectric generators including the above-described thermoelectric generators, a high-temperature fluid as a heat source is circulated through a heat transfer tube provided at the center of the device, and a plurality of thermoelectric modules are banded from the periphery. Summary relates configured to fix the pressing state to the heat transfer tube surface by tightening and are mostly, by the tightness of the installation position and the band of the thermoelectric modules, etc., the contact surface between the high-temperature heat source and the thermoelectric module and the low temperature medium passage In many cases, the surface pressure was uneven and the performance was affected.

  In addition, by disposing the thermoelectric module around the heat transfer tube, not only can the heat exchange amount relative to the overall dimensions of the device, that is, the heat exchange density, be increased, but also the assembly is not easy and not suitable for mass production. It was.

  Therefore, for example, application to an exhaust pipe of an internal combustion engine such as an automobile is limited in installation location, and it is difficult to install a sufficient number of thermoelectric modules satisfying the required output in a state satisfying appropriate performance. Also, it was difficult to reduce production costs.

  The present invention has been made in view of such articles, and by installing the thermoelectric module in an appropriate pressing state, it realizes efficient conversion from heat energy to electric energy, and achieves light weight and high performance power generation. An object of the present invention is to provide a thermoelectric generator capable of obtaining functions and having excellent structural soundness and workability such as attachment and maintenance.

In order to achieve the above object, in the present invention, a thermoelectric module incorporating a thermoelectric conversion element that converts thermal energy due to a temperature difference between a high temperature medium and a low temperature medium into electric energy, and recovering the thermal energy of the high temperature medium. A high-temperature medium flow path for heating the thermoelectric module; and a low-temperature medium flow path arranged to intersect with the high-temperature medium flow path to remove heat by the low-temperature medium and cool the thermoelectric module. In the thermoelectric power generation apparatus arranged to be sandwiched between the medium flow path and the low temperature medium flow path, the even number of high temperature medium flow paths are arranged radially with respect to the high temperature medium flow direction, the thermoelectric module is arranged on both sides, the low temperature medium passage so as to sandwich the thermoelectric module was installed between the adjacent hot medium flow passage, arrangement in a direction crossing the high temperature medium flow direction Through fastening members between low temperature medium passage facing is to provide a thermoelectric generator, characterized in that fixed by sandwiching the thermoelectric module at a high temperature medium flow path and the low temperature medium passage.

In the above configuration, desirably, even flat hot medium flow tubes are arranged radially with respect to the hot medium flow direction, thermoelectric modules are arranged on both sides of the flat hot medium flow tubes, and the adjacent flat A low temperature medium flow block is installed so that a thermoelectric module is sandwiched between a hot medium flow tube and a pair of low temperature medium flow blocks facing each other in a direction crossing the high temperature medium flow direction. The thermoelectric module is sandwiched and fixed between a flat high temperature medium flow tube and a low temperature medium flow block with a uniform and sufficient surface pressure through the member.

In the thermoelectric generator according to the present invention, the low-temperature medium flow path block has an L-shaped or V-shaped cross-section perpendicular to the flow direction of the low-temperature medium, and contributes to heat transfer away from the heat transfer surface. It is desirable to omit the few parts and to provide the fastening member support surface at the part facing the apex of the L-type or V-type.

In the thermoelectric power generation device according to the present invention, a connection component is installed on at least one of the inner peripheral side central portions of the arranged low temperature medium flow path blocks on the medium inlet side and the medium outlet side of the low temperature medium flow path block. It is desirable that each low-temperature medium flow path block is connected by piping through the connection parts, and the low-temperature medium is divided or joined to each low-temperature medium flow path block by the connection parts.

Further, as a thermoelectric generator according to the present invention, in the medium inlet and medium outlet side of the low temperature medium passage block, each low temperature medium passage block at least one of the outer peripheral side of the deployed low temperature medium passage block cyclic Alternatively, it is desirable to connect the pipes to a C-type, and to split or join the low-temperature media to the respective low-temperature medium flow path blocks by the annular or C-type pipes.

  Furthermore, as the thermoelectric generator according to the present invention, the thermoelectric module is hermetically sealed so that the module internal space is blocked from the module external space, and the atmosphere of the internal space is an inert gas or a vacuum. desirable.

Each low-temperature medium channel block has two pressing surfaces, and many thermoelectric modules can be pressed and fixed with a small number of low-temperature medium channel blocks and fastening members.

In addition, the low-temperature medium flow path block is configured as a pair of two sets facing each other in the direction (radial direction) orthogonal to the high-temperature medium flow direction and fastened by a fastening member. The pressing of the other set of low-temperature medium flow path blocks does not decrease by the tightening.

As a result, a large number of thermoelectric modules can be simply sandwiched between the high-temperature medium flow path tube and the low-temperature medium flow path block and installed in an appropriate pressed state with a few fastening points.

The cross-sectional shape perpendicular to the flow direction of the low-temperature medium in the low- temperature medium flow path block is L-type or V-type, omits a portion that contributes less to the heat transfer away from the heat transfer surface, and the top of the L-type or V-type As a result of providing the fastening member support surface at the portion opposite to the surface, it is possible to reduce the weight of the low-temperature medium flow path block, and a separate structure for supporting the fastening member is not necessary and is disposed. Therefore, the fastening member does not protrude to the outer peripheral side of the low temperature medium flow path block, and the thermoelectric generator can be made small and light.

By dividing or joining the low-temperature medium to each low-temperature medium flow path block by the connecting part or the annular or C-shaped pipe, the medium introduction pipe from the external cooling equipment to the low-temperature medium flow path block and the external cooling equipment The number of connected medium discharge pipes is sufficient for each of the inlet side and the outlet side, so that the pipe connection workability is improved and the space required for the pipes between the respective low-temperature medium flow path blocks can be reduced. .

  The thermoelectric module is hermetically sealed, and the atmosphere of the internal space is an inert gas or a vacuum, so that the thermoelectric conversion element incorporated therein can be prevented from being deteriorated due to oxidation or the like even in a high temperature atmosphere. Therefore, even when used at a high temperature, a light-weight and high-performance power generation function can be obtained, and structural soundness can be ensured.

The perspective view which shows the whole structure of the thermoelectric power generator by 1st Embodiment of this invention. 1 is an exploded view of a thermoelectric generator according to a first embodiment of the present invention. Sectional drawing cut | disconnected by the surface perpendicular | vertical to the flow of the high temperature medium of the thermoelectric generator by 1st Embodiment of this invention (III-III sectional view taken on the line of FIG. 1). The perspective view which shows the whole structure of the thermoelectric power generator by 2nd Embodiment of this invention. Sectional drawing cut | disconnected by the surface perpendicular | vertical to the flow of the high temperature medium of the thermoelectric generator by 2nd Embodiment of this invention (VV sectional view taken on the line of FIG. 4).

  Hereinafter, embodiments of a thermoelectric generator according to the present invention will be described with reference to the drawings.

  In the following embodiment, for example, a thermoelectric generator for mounting on a car will be described as an example, but the present invention can be implemented by appropriately mounting on various mobile devices other than a car.

[First Embodiment (FIGS. 1 to 3)]
FIG. 1 is a perspective view showing an overall configuration of a thermoelectric generator according to a first embodiment of the present invention.

As shown in FIG. 1, the thermoelectric generator 1 of the present embodiment mainly includes a flat high-temperature medium flow tube 2 into which a high-temperature medium from a heat source (not shown) flows and one flat high-temperature medium flow tube 2. A thermoelectric module 3 that receives heat by contacting the surface, and a low-temperature medium channel block that cools the other surface of the thermoelectric module 3 by circulating a low-temperature medium supplied from an external cooling facility (not shown) through the internal low- temperature medium channel 4 is constituted. That is, in this embodiment, the low-temperature medium flow path block 4 is connected by piping in the center portion on the inner peripheral side of the thermoelectric generator 1.

  FIG. 2 is an exploded view of the thermoelectric generator, and FIG. 3 is a cross-sectional view taken along a plane perpendicular to the flow of the high-temperature medium of the thermoelectric generator (cross-sectional view taken along line III-III in FIG. 1).

As shown in FIGS. 1, 2, and 3, the thermoelectric generator 1 of the present embodiment mainly includes a flat high-temperature medium flow tube 2 into which a high-temperature medium from a heat source (not shown) flows, a flat high-temperature medium flow A thermoelectric module 3 that receives heat by contacting one surface of the path tube 2 and a low-temperature medium flow path that cools the other surface of the thermoelectric module 3 by circulating a low-temperature medium supplied from an external cooling facility (not shown) inside Configured by block 4. A low temperature medium flow path 15 is formed in the low temperature medium flow path block 4.

  Flat high-temperature medium flow path tubes 2 made of an even number of flat-shaped tubes are arranged radially with respect to the high-temperature medium flow direction.

Thermoelectric modules 3 are arranged on both sides of the flat high-temperature medium flow tube 2, and the low-temperature medium flow block 4 is installed so that the thermoelectric module 3 is sandwiched between the adjacent flat high-temperature medium flow tubes 2. .

The thermoelectric module 3 is connected to the flat high-temperature medium flow tube 2 with a uniform and sufficient surface pressure through the fastening member 5 through a set of two low-temperature medium flow channel blocks 4 facing each other in the direction intersecting the high-temperature medium flow direction. It is configured to be sandwiched and fixed by the low-temperature medium flow path block 4.

  In order to relieve the thermal stress of the flat high temperature medium flow tube 2, for example, a bellows thermal expansion absorbing mechanism 6 is provided upstream or downstream of the high temperature medium flow channel.

  The flat high temperature medium flow tube 2 is mainly required to have high temperature strength and thermal conductivity. When the high temperature medium is corrosive, further corrosion resistance is required. Therefore, in the present embodiment, for example, stainless steel, copper alloy, aluminum alloy or the like is applied as the material of the flat high temperature medium flow tube 2. In addition, as a manufacturing method of the flat high temperature medium flow path tube 2, brazing, welding, shaping | molding of a circular pipe, etc. are applicable, for example.

  In addition, it is effective to install fins in the flat high-temperature medium flow tube 2 for promoting heat transfer and improving pressure resistance.

  Furthermore, the thermoelectric module 3 may have a plate-like configuration, and the outer shape is not limited to the rectangular shape shown in the figure.

  Further, the thermoelectric module 3 may be hermetically sealed so that the atmosphere inside the module including a thermoelectric conversion element (not shown) incorporated in the thermoelectric module 3 is an inert gas or a vacuum. For example, a gigatopaz (registered trademark) module already proposed by the applicant can be used.

The low-temperature medium flow path block 4 is mainly required to have thermal conductivity, strength, and light weight. As a material of the low-temperature medium flow path block 4, for example, aluminum alloy, stainless steel, copper alloy, resin or the like can be used. As a manufacturing method of the low-temperature medium flow path block 4, for example, extrusion, brazing, welding, or the like can be applied. As the fastening member 5, for example, bolts, nuts, screws, and the like can be used.

In the present embodiment, the number of flat high-temperature medium flow tubes 2 is four, but the number of flat high-temperature medium flow tubes 2 may be an even number of 4 or more. In this configuration, the low- temperature medium flows in the low-temperature medium flow path block 4 as a parallel flow or a counterflow with respect to the high-temperature medium.

Moreover, the cross-sectional shape orthogonal to the flow direction of the cooling medium in the low-temperature medium flow path block 4 is, for example, L-shaped or V-shaped. And the fastening member support surface 7 is provided in the site | part which opposes the top of L type or V type, omitting the site | part with little contribution to the heat transfer away from the heat transfer surface. In this case, about the shape of the fastening member support surface 7, it does not necessarily need to be a plane and can be implemented as various shapes.

In this embodiment, the fastening member 5 and the fastening member support surface 7 are used to absorb and suppress changes in fastening force due to thermal expansion of the flat high temperature medium passage tube 2, the low temperature medium passage block 4 and the fastening member 5. It is good also as a structure which incorporates the elastic body 8 between. Moreover, as the elastic body 8, various elastic materials, such as a spring washer and rubber | gum, are applicable, for example.

Note that a cross-shaped connecting component 9 is installed at the inner peripheral side central portion of the arranged low temperature medium flow path block 4 on the medium inlet side and medium outlet side of the low temperature medium flow path block 4. Pipe connections of the respective low-temperature medium flow path blocks 4 are made through the connection parts 9. Then, each one of the medium introduction pipe from the external cooling facility and the medium discharge pipe to the external cooling facility is connected to the low temperature medium flow path block 4 on the medium inlet side and the medium outlet side. In addition, on the inlet side, the low temperature medium flow path block 4 is divided by the connecting component 9 and on the outlet side, the low temperature medium is joined.

In this case, the connection part of the connection component 9 is, for example, a convex type or a concave type, and is fitted into a connection part such as a concave type or a convex type provided in the low-temperature medium flow path block 4 and sealed with an O-ring or the like. It is as.

According to this embodiment having such a configuration, each low-temperature medium flow path block 4 has two pressing surfaces, and many thermoelectric modules are pressed and fixed by a small number of low-temperature medium flow path blocks and fastening members. It becomes possible.

The low-temperature medium flow path block 4 is configured as a pair of two bodies facing each other in a direction (radial direction) orthogonal to the high-temperature medium flow direction, and is fastened by a fastening member. By tightening the fastening members, the pressing of the other sets of the low-temperature medium flow path blocks 4 does not decrease.

With this configuration and action, in this embodiment, a large number of thermoelectric modules 3 are simply sandwiched between the flat high-temperature medium flow tube 2 and the low-temperature medium flow block 4 with a few fastening points, and an appropriate pressing state is achieved. Can be installed at.

And the cross-sectional shape orthogonal to the flow direction of the cooling medium of the low-temperature medium flow path block 4 is L type or V type, for example. According to this configuration, as a result of omitting the portion that contributes less to the heat transfer away from the heat transfer surface and providing the fastening member support surface 7 at the portion facing the apex of the L-type or V-type, the low-temperature medium flow path The weight of the block 4 can be reduced, and a separate structure for supporting the fastening member 5 is not necessary. Moreover, the fastening member 5 does not protrude to the outer peripheral side of the arranged low-temperature medium flow path block 4, and the thermoelectric generator 1 can be made small and light.

Further, according to the present embodiment, as a result of dividing or joining the low temperature medium to each low temperature medium flow path block 4 by the connecting component 9, the annular or C-shaped pipe, the low temperature medium flow path block 4 from the external cooling facility The number of connections of the medium introduction pipe and the medium discharge pipe to the external cooling facility is sufficient for each of the inlet side and the outlet side. For this reason, while being able to improve the connection workability | operativity of piping, it becomes possible to make small the space required for piping between each low-temperature- medium flow path block 4. FIG.

  In addition, since the thermoelectric module 3 according to the present embodiment has a hermetically sealed configuration and the atmosphere in the internal space is an inert gas or a vacuum, deterioration due to oxidation or the like with respect to the thermoelectric conversion element incorporated in the high-temperature atmosphere is also achieved. Impact is prevented. Therefore, even when used at a high temperature, it is possible to obtain a light-weight and high-performance power generation function and to ensure structural soundness.

[Second Embodiment (FIGS. 4 and 5)]
4 is a perspective view showing the overall configuration of the thermoelectric generator according to the second embodiment of the present invention, and FIG. 5 is a cross-sectional view taken along the line V-V of FIG. 4 (on a plane perpendicular to the flow of the high-temperature medium of the thermoelectric generator). FIG.

  In the present embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals in FIGS. 4 and 5 as those in the first embodiment, and redundant description is omitted.

In this embodiment, each low temperature medium passage block 4 on the outer peripheral side of the low temperature medium passage block 4 located in the medium inlet and medium outlet side of the low temperature medium passage block 4, annular or C-type by a connecting hose 10 It is configured as a pipe connection.

One medium introduction pipe from the external cooling facility and one medium discharge pipe to the external cooling facility are connected to the inlet-side and outlet-side annular or C-shaped pipes 11 respectively. And it is set as the structure which makes each cold medium flow path block 4 branch by the cyclic | annular or C type piping 11, and each cold medium 13 joins by the exit side.

  In addition, as a material of the connection hose 10, it is possible to apply rubber, resin, metal, etc., for example, considering the property, temperature, etc. of the low-temperature medium 13.

[Other Embodiments]
In the present invention, various configurations can be made without changing the gist by combining the configuration of the first embodiment and the configuration of the second embodiment described above and adding appropriate additional parts.

  For example, the first embodiment can be applied to the cold medium inlet side, the second embodiment can be applied to the cold medium outlet side, and other configurations can be added.

  Further, the pipe connection portion with the external cooling facility is not particularly limited to the configuration of each of the above-described embodiments.

For example, in the first embodiment, the pipe from the external cooling facility may be directly connected to the connection component 9. Further, in the second embodiment, for example, the pipe from the external cooling facility is connected to the low-temperature medium flow path block 4. It is also possible to make various structural modifications.

Further, even-numbered hot medium flow paths are arranged radially with respect to the hot medium flow direction, thermoelectric modules are arranged on both sides of the hot medium flow path, and the thermoelectric modules are sandwiched between adjacent hot medium flow paths. A low temperature medium flow path is installed, a fastening member is passed through a set of two low temperature medium flow paths facing each other in a direction crossing the high temperature medium flow direction, and the thermoelectric module is sandwiched between the high temperature medium flow path and the low temperature medium flow path. It can implement as a structure which added the other various members with respect to the element fixed by.

DESCRIPTION OF SYMBOLS 1 Thermoelectric power generator 2 Flat high temperature medium flow path tube 3 Thermoelectric module 4 Low temperature medium flow path block 5 Fastening member 6 Thermal expansion absorption mechanism 7 Fastening member support surface 8 Elastic body 9 Connection component 10 Connection hose 11 Pipe 12 High temperature medium 13 Low temperature Medium 14 High-temperature medium flow path 15 Low-temperature medium flow path

Claims (5)

A thermoelectric module incorporating a thermoelectric conversion element that converts thermal energy due to a temperature difference between the high temperature medium and the low temperature medium into electrical energy; a high temperature medium flow path that recovers the thermal energy of the high temperature medium and heats the thermoelectric module; A low-temperature medium flow path that is arranged to intersect with the high-temperature medium flow path and removes heat by the low-temperature medium and cools the thermoelectric module, and the thermoelectric module is located between the high-temperature medium flow path and the low-temperature medium flow path. In the thermoelectric generator set to be sandwiched between
Even-numbered hot medium flow paths are arranged radially with respect to the hot medium flow direction, thermoelectric modules are arranged on both sides of the hot medium flow path, and the thermoelectric modules are sandwiched between adjacent hot medium flow paths. to set up a media channel, through fastening members between low temperature medium passage facing arranged in a direction intersecting with the hot medium flow direction, and fixed by sandwiching the thermoelectric module at a high temperature medium flow path and the low temperature medium passage A thermoelectric generator characterized by. 2. The low-temperature medium flow path according to claim 1, wherein a cross-sectional shape perpendicular to the flow direction of the cooling medium is L-shaped or V-shaped, and a fastening member support surface is provided at a portion facing the apex of the L-shaped or V-shaped. Thermoelectric generator. A connecting component is installed on at least one of the center portion on the inner peripheral side of the low-temperature medium flow channel on the medium inlet side and the medium outlet side of the low-temperature medium flow channel, and each cooling medium flow channel is connected by piping through the connecting component, The thermoelectric generator according to claim 1 or 2, wherein the low temperature medium is divided or merged into the low temperature medium flow paths by the connecting parts. Each cooling medium flow path is connected to at least one of the outer side of the low temperature medium flow path on the medium inlet side and the medium outlet side of the low temperature medium flow path in a ring shape or a C shape, The thermoelectric generator according to any one of claims 1 to 3, wherein the low-temperature medium is divided or joined to the low-temperature medium flow path. The thermoelectric module is hermetically sealed so that a module internal space in which the thermoelectric conversion element is incorporated is cut off from a module external space, and the internal space is an inert gas atmosphere or a vacuum. Item 5. The thermoelectric power generator according to any one of items 4 to 5.

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