JP2015135928A - Thermoelectric conversion power generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermoelectric conversion power generator capable of suppressing damage on a thermoelectric conversion element effectively, by reducing a stress applied to the thermoelectric conversion element.SOLUTION: In a power generator generating power by providing a cooling jacket 3 on the outer surface side of a tube body 25, disposing a thermoelectric conversion module 4 while sandwiching between the main plate 251 of the tube body 25 and cooling jacket 3, and then giving a temperature difference to the thermoelectric conversion module 4 by means of the tube body 25 heated by heating fluid H and cooling jacket 3, rigidity of the tube body 25 is reduced by forming an elastically deformable recess 255 projecting inward in the side plate 252 of the flat tube body 25, thereby making the main plate 251 deformable and making the thermoelectric conversion element 41 of the thermoelectric conversion module 4 less likely to be damaged.

Description

  The present invention relates to a thermoelectric power generation apparatus that converts a thermal energy into an electrical energy by giving a temperature difference to a thermoelectric conversion module.

  A power generation technique for converting thermal energy into electrical energy using a thermoelectric conversion element is known. The thermoelectric conversion element uses a Seebeck effect that causes a potential difference between a high temperature part and a low temperature part by giving a temperature difference to a separated part, and the power generation amount increases as the temperature difference increases. Such a thermoelectric conversion element is used in the form of a thermoelectric conversion element module in which a plurality are joined by electrodes. For example, by laminating a thermoelectric conversion module and a cooling part on the outer surface of the pipe body and introducing a heating fluid into the pipe body, the space between the heated pipe body (high temperature part) and the cooling part (low temperature part) 2. Description of the Related Art A thermoelectric conversion power generator having a configuration in which electricity is extracted by causing a temperature difference in a thermoelectric conversion module sandwiched between two is known (Patent Document 1).

JP 2006-217756 A

  In the thermoelectric conversion power generation device having the above configuration, thermal stress due to a difference in thermal expansion is generated in the thermoelectric conversion element of the thermoelectric conversion module to which a temperature difference is given between the high temperature portion and the low temperature portion. Since the thermoelectric conversion element is joined to the tubular body via the high temperature side electrode, the thermal stress generated in the thermoelectric conversion element is transmitted to the tubular body and tries to deform the tubular body. However, since the tube is usually made of a metal such as stainless steel and has rigidity, it is difficult to deform. Therefore, the thermoelectric conversion element receives stress from the tube, and as a result, the thermoelectric conversion element is cracked. Or damage may occur.

  The present invention has been made in view of the above circumstances, and a main problem thereof is to provide a thermoelectric conversion power generation device that can reduce the stress applied to the thermoelectric conversion element and effectively suppress breakage of the thermoelectric conversion element. It is in.

  The thermoelectric conversion power generation device of the present invention includes a pipe body including a pair of opposed heating plate portions and side plate portions that connect both side portions of the heating plate portions, and in which a pipe line through which a heating fluid flows is formed. A cooling part disposed on the outer surface side of the heating plate part, and a thermoelectric conversion module having a thermoelectric conversion element disposed between the heating plate part and the cooling part, and the heating plate part In the thermoelectric conversion power generation device that generates power by applying a temperature difference to the thermoelectric conversion module by the cooling unit, the side plate portion of the tubular body is capable of deforming the heating plate portion at least partially. It has a flexible part.

  In the present invention, the heating plate portion is heated by the heating fluid flowing through the pipe line in the pipe body, and the heat is transmitted to the inner surface side (pipe body side) of the thermoelectric conversion module and heated. On the other hand, the outer surface side of the thermoelectric conversion module is cooled by the cooling unit, thereby generating a temperature difference in the thermoelectric conversion module and generating power. Since the tube body has a flexible portion in the side plate portion, the rigidity is suppressed from increasing, and the heating plate portion can be deformed by the deformation of the flexible portion. Therefore, the heating plate portion is deformed in accordance with the thermal stress applied to the thermoelectric conversion element, and the stress that the thermoelectric conversion element receives from the heating plate portion is reduced as compared with the conventional case. As a result, damage to the thermoelectric conversion element can be effectively suppressed.

The present invention includes the following forms.
The flexible portion is an elastically deformable portion that is elastically deformed. Further, the flexible part has any one of a concave shape that protrudes inward of the tubular body, a convex shape that protrudes outward of the tubular body, and a bellows shape.

  Further, the present invention is characterized in that fins for collecting heat of the heating fluid and transmitting it to the heating plate portion are disposed in the pipe line. In this embodiment, the heat of the heating fluid flowing inside the tube body is collected by the fins and transmitted to the pair of heating plate portions, and the heating plate portions are increased in temperature and the power generation efficiency is improved.

  ADVANTAGE OF THE INVENTION According to this invention, there exists an effect that the damage concerning a thermoelectric conversion element can be effectively suppressed by reducing the stress concerning a thermoelectric conversion element.

1 is an overall perspective view of a thermoelectric conversion power generator according to an embodiment of the present invention. It is an II directional arrow line view of FIG. FIG. 3 is a sectional view taken along line III-III in FIG. 2. It is IV-IV sectional drawing of FIG. It is a perspective view which shows the structure of the housing | casing of the airtight container with which the same electric power generating apparatus is provided. It is a front view of the tubular body with which the power generator is provided. FIG. 5 is a partially enlarged view of FIG. 4, and is a cross-sectional view illustrating a configuration of a thermoelectric conversion module and fins. It is a front view which shows the tubular body which concerns on other embodiment.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
[1] Configuration of Thermoelectric Conversion Power Generation Device FIGS. 1 to 4 show a thermoelectric conversion power generation device (hereinafter referred to as a power generation device) 1 according to an embodiment. FIG. 1 is an overall perspective view, and FIG. II direction view, FIG. 3 and FIG. 4 are a III-III sectional view and an IV-IV sectional view of FIG. 2, respectively. This power generator 1 is formed in a flat rectangular parallelepiped shape (the X direction is the longitudinal direction in FIGS. 1, 3, and 4), and is housed in a water cooling jacket (cooling portion) 3 and the water cooling jacket 3. A sealed container 2 is provided.

  The sealed container 2 has a double tube structure in which a flat tubular tube 25 is housed in the center of the flat tubular housing 20, and the space between the housing 20 and the tubular body 25 is decompressed. The opening at both ends in the X direction of the decompression space 29 is hermetically closed by the sealing cover 26. The water-cooling jacket 3 is formed in a flat tubular shape substantially along the outer shape of the sealed container 2, and the sealed container 2 housed therein has both end portions on the opening side projecting from both end openings of the water-cooled jacket 3.

  As shown in FIG. 5, the housing 20 is composed of a rigid portion 21 as a main body and a rectangular thin plate 22 joined to the rigid portion 21. The rigid portion 21 includes a pair of frames having a rectangular outer frame plate portion 211 and an inner frame plate portion 212 that partitions the inside of the outer frame plate portion 211 into two rectangular holes 213 divided in the longitudinal direction (X direction). The plates 210 face each other in parallel in the vertical direction (Z direction), the edges along the longitudinal direction of the outer frame plate portion 211 are connected by the side plate portions 215, and open at both ends in the longitudinal direction. It has the opening pipe part 217 which forms 218. FIG.

  The thin plate 22 is formed in a rectangular shape having a size that covers the two holes 213 of the rigid portion 21 with a flexible elastically deformable plate material. The thin plate 22 is joined to the periphery of the hole 213 on the outer surface of each frame plate 210 by a joining means such as brazing, whereby the two holes 213 are closed by the single thin plate 22. The material of the thin plate 22 is preferably a metal plate having heat resistance and oxidation resistance, such as stainless steel or aluminum such as SUS444, and the thickness thereof is, for example, about 0.1 mm.

  As shown in FIGS. 3, 4, and 6, the tubular body 25 housed in the housing 20 has a pair of upper and lower flat rectangular main plate portions 251 parallel to the upper and lower frame plates 210 of the housing 20. Are connected by side plate portions 252 parallel to the side plate portions 215 of the housing 20, and the outer surfaces of the opening edges at both ends are the opening tube portions 217 of the rigid portion 21 of the housing 20. The inner surface is joined via an oval sealing cover 26 having a U-shaped cross-section that is recessed inward.

  As shown in FIG. 6, the side plate portion 252 of the tube body 25 is not flat, but has a recess (flexible portion, elastic deformation portion) 255 having a shape in which the cross-sectional shape is dented inward of the tube body 25. Yes. The concave portion 255 can be bent and elastically deformed. When stress is applied to the main plate portion 251 of the tube body 25, the concave portion 255 is deformed, and the main plate portion 251 is bent and deformed so as to warp inward or outward. It is possible to do.

  The inside of the pipe body 25 is formed as a pipe line 253 through which the heating fluid H (see FIGS. 3 and 4) flows from one opening toward the other opening. The fins 7 that collect and transfer the heat to the tube body 25 are disposed.

  As shown in FIG. 7, in this case, the fins 7 are provided in a pair of upper and lower states, one in contact with the upper main plate portion 251 and one in contact with the lower main plate portion 251. The fin 7 is formed of a bellows-like corrugated plate in which V-shaped portions 71 bent in a substantially V-shaped cross-section are formed by bending a single plate material, and a tip portion 711 of the V-shaped portion 71 is formed. It is joined to the main plate portion 251 by joining means such as brazing. In this joined state, there is a predetermined gap between the upper and lower fins 7 (in FIG. 2 and FIG. 4, they are in contact but are actually spaced). The heating fluid H flowing through the pipe 253 passes through the tunnel-shaped space 712 in the V-shaped portion 71 while being in contact with the main plate portion 251 and the fins 7. The fin 7 is manufactured using a metal plate having a heat resistance and an oxidation resistance such as stainless steel such as SUS444 or aluminum and having a plate thickness of, for example, about 0.1 mm, for example, like the thin plate 22.

  The same material as that of the thin plate 22 is used for the rigid portion 21, the tubular body 25, and the sealing cover 26 of the casing 20 that constitute the sealed container 2. A plurality of thermoelectric conversion modules 4 are respectively disposed between the thin plate 22 of the casing 20 and the main plate portion 251 of the tubular body 25 of the sealed container 2.

  As shown in FIG. 7, the thermoelectric conversion module 4 includes electrodes 42 made of a metal plate such as a rectangular copper plate on one side and the other side of a plurality of thermoelectric conversion elements 41 arranged in a plane. Thus, the electrode 42 on one surface side is joined to the outer surface of the main plate portion 251 of the tubular body 25 by a joining means such as brazing. The electrode 42 on the other side faces the inner surface of the thin plate 22 of the housing 20, and the buffer material 5 is held between the thin plate 22 and the electrode 42. The thin plate 22 and the buffer material 5 and the buffer material 5 and the electrode 42 are not joined, but are in contact with each other so as to be slidable. In this case, one thermoelectric conversion module 4 is incorporated in parallel with the thin plate 22 that closes one hole 213 of the housing 20, and a total of four thermoelectric conversion modules 4 are equipped. The electrode 42 is insulated from the tube body 25 and the buffer material 5.

  The buffer material 5 is preferably a flexible sheet-like material such as a thin carbon sheet. In the present embodiment, the buffer material 5 is sandwiched between the thin plate 22 and the thermoelectric conversion module 4. However, the buffer material 5 is used as necessary, and the thin plate 22 directly contacts the thermoelectric conversion module 4. Can be selected.

  As the thermoelectric conversion element 41 constituting the thermoelectric conversion module 4, a type having a high heat-resistant temperature is used. For example, a silicon-germanium system, a magnesium-silicon system, a manganese-silicon system, an iron silicide system, or the like is preferably used. The decompression space 29 of the sealed container 2 in which the thermoelectric conversion module 4 is housed is hermetically sealed by a casing 20, a tubular body 25, and a sealing cover 26 that are formed of the rigid portion 21 and the thin plate 22. As shown in FIG. 4, the fin 7 has a size corresponding to the thermoelectric conversion module 4, and the thermoelectric conversion module 4 is disposed on both sides of the fin 7.

  The sealed container 2 is stored in a water-cooled jacket 3. As shown in FIGS. 3 and 4, the water-cooling jacket 3 has a sealing frame portion 31 that is bent inward and formed on the opening edges at both ends, on the outer surface of the outer frame plate portion 211 of the rigid portion 21 in the sealed container 2. And airtightly joined by means such as brazing. A space in the water cooling jacket 3, that is, a space formed between the rigid portion 21 and the water cooling jacket 3 is a cooling space 32 for cooling the thin plate 22 by supplying cooling water. A cooling water inlet / outlet 33 is provided at a central portion of the water cooling jacket 3 corresponding to each side plate portion 215 of the housing 20.

  A total of four thermoelectric conversion modules 4 are accommodated in the sealed container 2, and these thermoelectric conversion modules 4 are connected in series. Then, electricity is taken out from the two lead wires 49 of + • − shown in FIGS. The lead wire 49 passes through the side plate portion 215 and the water cooling jacket 3 of the sealed container 2 and is drawn to the outside, and the lead wire through hole of the side plate portion 215 and the water cooling jacket 3 is hermetically closed.

  The heat exchange means 6 is joined to the thin plate 22 at a location corresponding to the thermoelectric conversion module 4 in the cooling space 32. The heat exchange means 6 is provided in a state in which the cooling of the thin plate 22 is not hindered by the cooling water supplied to the cooling space 32 being brought into contact to dissipate the thin plate 22 to promote cooling.

  Examples of the heat exchanging means 6 include a heat exchanging member such as a fin having flexibility that does not hinder the flexibility of the thin plate 22. Moreover, even if it is a heat exchange member such as a hard fin, a plurality of independent heat exchange members are provided in contact with the thin plate 22 in a scattered manner so as not to hinder the flexibility of the thin plate 22. Also good.

  The sealed container 2 sucks air in the decompression space 29 from a decompression sealing port (not shown) formed at a predetermined location to decompress the decompression space 29 to a predetermined pressure (for example, about 1 to 100 Pa). Are hermetically sealed by welding or the like. As a result, in the sealed container 2, a pressure difference is generated in which the pressure in the decompression space 29 is lower than that in the outside atmosphere, and the force that pressurizes the thin plate 22 of the housing 20 toward the thermoelectric conversion module 4 due to the pressure difference. Receive.

[2] Action of Power Generation Device In the power generation device 1 having the above-described configuration, the pipe body 25 is heated by flowing a high-temperature heating fluid H from one opening to the other opening in the pipe line 253 of the pipe body 25. In addition, the cooling water is introduced into the cooling space 32 from one introduction outlet 33 of the water cooling jacket 3, the cooling water is discharged from the other introduction outlet 33, and the cooling space 32 is filled with the cooling water to be sealed. The thin plate 22 of the container 2 is cooled.

  The heat of the heating fluid H that flows through the pipe 253 directly heats the pair of opposing main plate portions 251 of the tube body 25, and is collected by the fins 7 and transmitted to each main plate portion 251, and the high temperature of the main plate portion 251. Is promoted. Heat of the main plate portion 251 of the heated tube body 25 is transmitted to the inner surface side of the thermoelectric conversion module 4, and the inner surface side of the thermoelectric conversion module 4 is heated. On the other hand, the cooling of the thin plate 22 is promoted by the heat exchange means 6 that is cooled by cooling water. The heat of the cooled thin plate 22 is transmitted to the outer surface side of the thermoelectric conversion module 4, and the outer surface side of the thermoelectric conversion module 4 is cooled. Thereby, a temperature difference is given to the thermoelectric conversion element 41 of the thermoelectric conversion module 4 so that the inner surface side is high temperature and the outer surface side is low temperature.

  In the hermetic container 2, the internal decompression space 29 is decompressed as described above to generate a pressure difference with the outside, whereby the thin plate 22 of the housing 20 is pressurized toward the thermoelectric conversion module 4. Thereby, the thin plate 22 of the housing | casing 20 is pressurized and closely_contact | adhered to the shock absorbing material 5, and the shock absorbing material 5 closely_contact | adheres in the state pressurized to the thermoelectric conversion module 4 side.

  As described above, a temperature difference is given between the outer surface side and the inner surface side of the thermoelectric conversion module 4, so that the thermoelectric conversion module 4 generates power and electricity is extracted from the lead wire 49. The heat of the heating fluid H that flows through the pipe 253 is collected by the fins 7 and transmitted to the pair of main plate portions 251, and the main plate portion 251 is heated to a high temperature and the power generation efficiency is improved.

  In the power generation apparatus 1 of this embodiment, for example, exhaust heat gas generated in a factory or a garbage incinerator, automobile exhaust gas, or the like is used as the heating fluid H.

[3] Effects of One Embodiment In the power generation apparatus 1 of the above-described embodiment, thermal stress due to a difference in thermal expansion is generated in the thermoelectric conversion element 41 of the thermoelectric conversion module 4 to which a temperature difference is given. The main plate portion 251 is deformed by being transmitted to the 25 main plate portions 251. Here, conventionally, since the tubular body has rigidity, the tubular body is difficult to be deformed. For this reason, the thermoelectric conversion element has a problem that it receives a stress from the tubular body and is cracked or broken.

  However, the tubular body 25 according to the present embodiment has an elastically deformable concave portion 255 formed in the side plate portion 252, so that an increase in rigidity is suppressed. For this reason, when the main plate portion 251 tries to deform, the concave portion 255 is bent and elastically deformed, so that the main plate portion 251 is easily deformed. Therefore, according to the thermal stress applied to the thermoelectric conversion element 41, the main plate portion 251 is bent and deformed so as to warp inward or outward. A pair of fins 7 are disposed between the main plate portions 251, but since the fins 7 are spaced apart from each other, the fins 7 do not interfere with each other and the main plate portion 251 is not deformed inward. Is possible. Since the main plate portion 251 can be deformed in this way, the stress applied to the thermoelectric conversion element 41 from the main plate portion 251 is reduced as compared with the conventional case, and as a result, the possibility that the thermoelectric conversion element 41 is damaged is reduced.

[4] Other Embodiments In the above embodiment, the entire side plate 252 in the height direction (Z direction in FIG. 2) is formed as a recess 255 that is elastically deformed. As long as a certain main plate portion 251 can be deformed, a flexible portion such as a concave portion 255 may be formed in at least a part of the side plate portion 252 in the height direction.

  In addition, the shape of the flexible portion of the present invention formed on the side plate portion 252 is not limited to the concave portion 255, and may be any shape as long as the main plate portion 251 can be deformed by deformation of itself. For example, as shown to Fig.8 (a), the cross-sectional shape formed in the convex shape which protrudes the outer side of a tubular body, or the cross-sectional bellows-like form shown in FIG.8 (b) can be considered. In either case, the main plate portion 251 can be deformed by bending and deforming itself.

  DESCRIPTION OF SYMBOLS 1 ... Thermoelectric conversion type generator, 25 ... Tube, 251 ... Main plate part (heating plate part), 252 ... Side plate part, 253 ... Pipe line, 255 ... Recessed part (flexible part, elastic deformation part), 3 ... Water cooling jacket (Cooling part) 4 ... thermoelectric conversion module, 41 ... thermoelectric conversion element, 7 ... fin, H ... heating fluid.

Claims (4)

A tube body having a pair of opposed heating plate portions and side plate portions that connect both side portions of these heating plate portions, and in which a pipe line through which a heating fluid flows is formed;
A cooling part disposed on the outer surface side of the heating plate part;
A thermoelectric conversion module having a thermoelectric conversion element disposed between the heating plate portion and the cooling portion;
With
In the thermoelectric conversion power generator that generates power by giving a temperature difference to the thermoelectric conversion module by the heating plate part and the cooling part,
The thermoelectric power generator according to claim 1, wherein the side plate portion of the tubular body has a flexible portion that can deform the heating plate portion at least in part.   The thermoelectric power generation apparatus according to claim 1, wherein the flexible portion is an elastically deformable portion that is elastically deformed.   3. The flexible portion according to claim 1, wherein a cross-sectional shape of the flexible portion is any one of a concave shape protruding inside the tubular body, a convex shape protruding outside the tubular body, and a bellows shape. Thermoelectric power generator.   The thermoelectric conversion power generator according to claim 1 or 2, wherein fins for collecting heat of the heating fluid and transmitting the heat to the heating plate portion are disposed in the pipe line.

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