JPH0817481A - Thermoelectric transducing device - Google Patents

Abstract

PURPOSE:To suppress temp. fall of a high temp. thermal medium in a heating part and also temp. rise of a low temp. thermal medium and to reduce the power required to transport the media by incorporating a boiling type heat supply device and condensation type heat radiation device. CONSTITUTION:Heat condition in a high temp. conduction part 501 takes place as a heat conduction of condensation of a high temp. thermal medium of saturated steam generated by a boiling type heat emission and supply device 100, and various parts of the conduction part 501 including the inlet and outlet to/from the power generation part and their surroundings can be given a constant temp. equal to that of the saturated steam. The liquid level in the supply device 100 is made identical to that in the conduction part 501 owing to the action of the graviation, and when the liquid in the device 100 evaporates and boils, the liquid in the conduction part 501 is transported effortlessly. A low temp. heat conduction part 502 in connection with a condensation type heat radiation device 600 works alike, and a power generation part 500 having a thermo-electric transducing element 530 performs a power generation with good efficiency.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermoelectric conversion device for generating power by giving a temperature difference to a thermoelectric conversion element by a heat medium.

[0002]

2. Description of the Related Art In recent years, in order to effectively use the exhaust heat of a heat engine, a fuel cell, an electronic device, etc., research and development of a thermoelectric conversion device for directly converting heat into electricity have been actively conducted. FIG. 4 shows a configuration example of a conventional thermoelectric conversion device. This apparatus includes a heat supply device 10, a high temperature heat medium circulation pipe 20, a high temperature heat medium 30, a high temperature heat medium circulation pump 40, a power generation unit 50, a heat dissipation device 60,
The low-temperature heat medium circulation pipe line 70, the low-temperature heat medium 80, and the low-temperature heat medium circulation pump 90 are included, and the power generation unit 50 includes a high-temperature heat transfer unit 51, a low-temperature heat transfer unit 52, and a thermoelectric conversion element 53.

The operation of this device is shown below. Heat supply device 1
0 heats and raises the temperature of the high temperature heat medium 30. The high-temperature heat medium circulation pump 40 conveys the high-temperature heat-medium 30 which has been heated and raised in temperature through the high-temperature heat-medium circulation pipe 20 and is supplied to the high-temperature heat transfer unit 51 in the power generation unit 50. On the other hand, the heat dissipation device 60
Cools and cools the low-temperature heat medium 80. The low temperature heat medium 80 that has been cooled and cooled is conveyed by the low temperature heat medium circulation pump 90 through the low temperature heat medium circulation pipe line 70, and is supplied to the low temperature heat transfer unit 52 in the power generation unit 50. Since the thermoelectric conversion element 53 in the power generation unit 50 is installed in contact with both the high temperature heat transfer unit 51 and the low temperature heat transfer unit 52, forced convection of the high temperature heat transfer medium 30 in the high temperature heat transfer unit 51. The heat transferred by means of flows through the thermoelectric conversion element 53 and is transferred to the low temperature heat transfer medium 80 in the low temperature heat transfer portion 52. At this time, since the thermoelectric conversion element 53 has a thermal resistance, a temperature difference is generated at both ends, thereby generating electric power.

[0004]

However, in this apparatus, since the heat is transferred by the sensible heat of the high temperature heat medium 30 and the low temperature heat medium 80, the temperature inside the high temperature heat transfer part 51 and the low temperature heat transfer part 52 is reduced. Is not constant depending on the location,
As shown in, the temperature of the high temperature heat medium 30 is high near the inlet of the power generation unit 50 because it is almost equal to the outlet temperature of the heat supply device 10, and the amount of heat is taken away and becomes lower as the temperature approaches the outlet of the power generation unit 50. On the contrary, the temperature of the low-temperature heat medium 80 depends on the power generation unit 50.
In the vicinity of the inlet, the temperature is almost the same as the outlet temperature of the heat dissipation device 60, but the temperature is low, but as the temperature approaches the outlet of the power generation unit 50, the amount of heat is given and increases. As a result, in the power generation unit 50,
Since the average temperature difference between the high temperature heat medium 30 and the low temperature heat medium 80 is always smaller than the temperature difference between the outlet of the heat supply device 10 and the outlet of the heat dissipation device 60, there is a problem that the conversion efficiency of the device is reduced.

As a means for solving this problem, a method of suppressing the temperature decrease of the high temperature heat medium 30 and the temperature increase of the low temperature heat medium 80 in the power generation section 50 by increasing the circulation speed of the high temperature heat medium 30 and the low temperature heat medium 80. However, in this case, the power consumption of the high temperature heat medium circulation pump 40 and the low temperature heat medium circulation pump 90 increases, and the conversion efficiency of the device decreases.

The present invention has been made in view of the above circumstances, and it is possible to suppress the temperature decrease of the high temperature heat medium and the temperature increase of the low temperature heat medium in the power generation section, and to reduce the power required to convey each heat medium. An object is to provide a possible thermoelectric conversion device.

[0007]

In order to achieve the above object, in the present invention, a fluid capable of gas-liquid two-phase transformation is used as a high temperature heat medium and a low temperature heat medium, and the heat supply device uses a liquid high temperature heat medium. Heat is applied by heating to saturated steam. The high-temperature heat transfer medium of saturated steam is transferred to the high-temperature heat transfer section in the power generation section through the high-temperature heat transfer medium circulation line, and condensed latent heat is transferred to the low-temperature heat transfer section via the thermoelectric conversion element by condensing in the high-temperature heat transfer section. . The liquid high-temperature heat medium generated by the condensation is circulated to the heat supply device. The low temperature heat transfer portion is filled with a liquid low temperature heat medium, and the heat given from the high temperature heat transfer portion causes the liquid low temperature heat medium to undergo saturated boiling to transfer the heat. The low-temperature heat transfer medium of saturated steam generated in the low-temperature heat transfer part is conveyed to the heat-dissipating part through the low-temperature heat transfer medium circulation line and condensed by being cooled, and becomes the liquid low-temperature heat transfer medium again and is circulated to the low-temperature heat transfer part. It

Further, the liquid level of the high temperature heat medium of the liquid generated by the condensation of the high temperature heat medium of the saturated vapor in the high temperature heat transfer section is equal to the liquid level of the high temperature heat medium of the liquid in the heat supply device. Install a heat supply device. Further, the heat dissipation device is installed at a height at which the liquid level of the liquid low temperature heat medium filled in the low temperature heat transfer portion and the liquid level of the liquid low temperature heat medium in the heat dissipation device are equal.

[0009]

By the above means, the heat transfer in the high temperature heat transfer part is performed by the condensation heat transfer of the high temperature heat medium of saturated steam, so that the temperature of the high temperature heat transfer part is supplied to the heat generation part regardless of the inlet and outlet. It can be kept constant at the same temperature as the saturated steam at the outlet of the device. Further, since heat transfer in the low temperature heat transfer section is performed by saturated boiling heat transfer of the low temperature heat medium of the liquid, the temperature of the low temperature heat transfer section is saturated liquid at the outlet of the radiator regardless of the vicinity of the inlet and the outlet of the power generation section. Can be constant at a temperature equal to Therefore, the average temperature difference between the high-temperature heat medium and the low-temperature heat medium in the power generation unit can be made equal to the temperature difference between the outlet of the heat supply device and the outlet of the heat dissipation device. It is possible to suppress a decrease in the efficiency of the device due to the temperature rise of the heat medium.

Further, since the action of making the liquid level of the high temperature heat medium of the liquid in the heat supply device equal to the liquid level of the high temperature heat medium of the liquid in the high temperature heat transfer portion always works by gravity, the liquid in the heat supply device is When the high-temperature heat medium of (1) is evaporated by boiling and the liquid level is lowered, the high-temperature heat medium of the liquid in the high-temperature heat transfer section is circulated to the heat supply device without power.

Similarly, since the action of equalizing the liquid level of the low temperature heat medium of the liquid in the low temperature heat transfer part and the liquid level of the low temperature heat medium of the liquid in the heat dissipation device always works by gravity, the low temperature heat transfer part When the liquid low-temperature heat medium is evaporated by boiling heat transfer and the liquid level is lowered, the liquid low-temperature heat medium in the heat dissipation device is supplied to the low-temperature heat transfer part without power.

Further, since the action of making the pressure of the saturated steam in the high temperature heat transfer section of the high temperature heat medium equal to the pressure of the saturated steam in the heat supply device always works, the saturated steam in the high temperature heat transfer section is always operated. When the high-temperature heat medium of 1 is condensed and the pressure is reduced, the high-temperature heat medium of saturated steam in the heat supply device is supplied to the high-temperature heat transfer part without power.

Similarly, since the pressure of the low-temperature heat medium of the saturated steam in the heat dissipation device and the pressure of the low-temperature heat medium of the saturated steam in the low-temperature heat transfer section are always equalized, the low temperature of the saturated steam is low in the heat dissipation device. When the heat medium condenses and the pressure drops, the low-temperature heat medium of saturated steam in the low-temperature heat transfer section is circulated to the heat dissipation device without power.

[0014]

Embodiments of the present invention will now be described in detail with reference to the drawings. (Embodiment 1) A first embodiment of the present invention is shown in FIG.

In this embodiment, the boiling heat supply device 100, the high temperature heat medium circulating pipe 200, the high temperature heat medium 300, and the power generation section 5 are used.
00, condensation type heat dissipation device 600, low temperature heat medium circulation conduit 70
0, a low-temperature heat medium 800, and a high-temperature heat medium 300
Is the high temperature saturated vapor 302 and the high temperature liquid 301, and the low temperature heat medium 800 is the low temperature saturated vapor 802 and the low temperature liquid 80.
Consists of one. In addition, the power generation unit 500 includes the high temperature heat transfer unit 50.
The thermoelectric conversion element 530 is composed of the low temperature heat transfer section 502 and the low temperature heat transfer section 502, and the liquid level of the high temperature liquid 301 in the high temperature heat transfer section 501 between the high temperature heat transfer section 501 and the low temperature heat transfer section 502. It is installed in contact with a position higher than the liquid level of the low temperature liquid 801 in the low temperature heat transfer unit 502.
The boiling heat supply apparatus 100 is installed at a height such that the liquid level of the high temperature liquid 301 in the boiling heat supply apparatus 100 can be made equal to the liquid level of the high temperature liquid 301 in the high temperature heat transfer section 501. Similarly, the condensation type heat dissipation device 600 is installed at a height such that the liquid level of the low temperature liquid 801 in the condensation type heat dissipation device 600 is equal to the liquid level of the low temperature liquid 801 in the low temperature heat transfer portion 502.

The operation of this embodiment is as follows. The boiling heat supply device 100 heats the high-temperature liquid 301 to bring it to a boil to form high-temperature saturated steam 302. The high temperature saturated steam 302 is conveyed to the high temperature heat transfer unit 501 through the high temperature heat medium circulation pipe line 200. In the high temperature heat transfer section 501, latent heat due to the condensation of the high temperature saturated steam 302 is caused to flow through the low temperature heat transfer section 502 via the thermoelectric conversion element 530. The high temperature liquid 301 generated by the condensation is recirculated to the boiling heat supply device 100 through the high temperature heat medium circulation pipe line 200. In the low temperature heat transfer unit 502, the low temperature liquid 801 is heated to saturated boiling by the heat that has flowed through, and the low temperature saturated steam 802
The saturated boiling heat transfer is performed by The low temperature saturated steam 802 generated in the low temperature heat transfer section 502 is recirculated to the condensing type heat dissipation device 600 through the low temperature heat medium circulation pipe line 700. In the condensation type heat dissipation device 600, the low temperature saturated vapor 802 is cooled and condensed to form a low temperature liquid 801. The low temperature liquid 801 generated by the condensation is conveyed to the low temperature heat transfer unit 502 through the low temperature heat medium circulation pipe line 700. In the power generation section 500, heat circulates from the high-temperature heat transfer section 501 to the low-temperature heat transfer section 502 via the thermoelectric conversion element 530, so that the thermal resistance of the thermoelectric conversion element 530 causes a temperature difference at both ends to generate electric power. . Further, since the action of making the liquid level of the high temperature liquid 301 in the boiling heat supply device 100 equal to the liquid level of the high temperature liquid 301 in the high temperature heat transfer part 501 always works by gravity, the high temperature in the boiling heat supply device 100 is high. When the liquid 301 evaporates due to boiling and the liquid level is lowered, the high-temperature liquid 301 in the high-temperature heat transfer section 501 is circulated to the boiling heat supply device 100 without power. Similarly, since the action of equalizing the liquid level of the low temperature liquid 801 in the low temperature heat transfer unit 502 and the liquid level of the low temperature liquid 801 in the condensation type heat dissipation device 600 always works due to gravity, the low temperature liquid in the low temperature heat transfer unit 502 is kept constant. 8
When 01 is evaporated by boiling heat transfer and the liquid level is lowered,
The low temperature liquid 801 in the condensing type heat dissipation device 600 is supplied to the low temperature heat transfer part 502 without power.

Further, since the action of making the pressure of the high temperature saturated steam 302 of the high temperature heat transfer section 501 equal to the pressure of the high temperature saturated steam 302 in the boiling heat supply apparatus 100 always works, the high temperature heat transfer section 501 has a high temperature. Saturated steam 302
Is condensed and the pressure is reduced, the boiling heat supply device 10
The high temperature saturated steam 302 in 0 is non-powered and the high temperature heat transfer unit 50
1 is supplied. Similarly, since the action of making the pressure of the low temperature saturated steam 802 in the condensing type heat dissipation device 600 equal to the pressure of the low temperature saturated steam 802 of the low temperature heat transfer part 502 always works, the low temperature saturated steam 8
When 02 is condensed and the pressure is reduced, the low temperature heat transfer unit 50
The low temperature saturated steam 802 of 2 is non-powered and the condensation type heat dissipation device 60
It is returned to 0.

In this embodiment, the boiling heat supply device 10 is used.
0 is a cast iron boiler, a vertical boiler, a furnace tube smoke tube boiler, a water tube boiler, a small once-through boiler, a liquid cooling type evaporator such as a liquid-filled shell-and-tube type evaporator, and a cross fin type fin-and-tube type evaporator. Various vaporizers such as gas-cooled evaporators such as reactors, and gas-liquid separators inside heat-generating devices such as phosphoric acid fuel cells that are pressure devices in which a saturated vapor phase and a saturated liquid phase are enclosed at the same time as the heat medium. Can be applied.

As the condensing radiator 600, various condensers such as a vertical condenser, a horizontal condenser, a double tube condenser, an atmospheric bleeder condenser, an evaporative condenser and an air condenser can be applied.

High temperature heat medium 300 and low temperature heat medium 800
As such, various halogen-containing compounds such as trichlorofluoromethane, dichlorofluoromethane, carbon tetrafluoride and chlorodifluoromethane, and fluids capable of gas-liquid transformation such as water can be applied.

As the thermoelectric conversion element 530, a physical battery using a thermoelectric semiconductor capable of generating power by applying a temperature difference across the element or an electrochemical temperature difference battery can be used.

As such a physical battery, an n-type p-type thermoelectric semiconductor of bismuth-tellurium type, lead-tellurium type, iron-silicon type, silicon-germanium type, bismuth-antimony type, gallium-phosphorus type is electrically used. It is possible to use a thermo module that is unitized by connecting in series with.

On the other hand, the electrochemical temperature difference battery has a function of arranging a chemical species that develops a thermoelectromotive force due to a change in redox potential depending on temperature between high and low temperature electrodes to generate electricity between temperature differences. It is a thermoelectric converter having, and it is possible to use a ferrocyan / ferrician redox pair, an iron ion redox pair, a redox battery using a chemical species such as bromine, and any power generation means capable of generating power by a temperature difference. (Embodiment 2) A second embodiment of the present invention is shown in FIG.

In the present embodiment, the boiling heat supply device 100 includes a phosphoric acid fuel cell 101 and a fuel cell cooling water circulation conduit 10.
2. It is composed of a steam separator 103. In this embodiment, the high temperature liquid 301 condensed in the high temperature heat transfer section 501 is recirculated to the steam separator 103 through the high temperature heat medium circulation pipe line 200. The high-temperature liquid 301 in the steam separator 103 is supplied to the fuel cell 101 through the fuel cell cooling water circulation line 102, and is boiled by the heat generation of the fuel cell 101 to become the high temperature saturated vapor 302, and the fuel cell cooling water circulation line 1
It is recirculated to the steam separator 103 through 02. The high temperature saturated steam 302 in the steam separator 103 is supplied to the high temperature heat transfer section 501 through the high temperature heat medium circulation pipe line 200.

A bismuth-tellurium-based physical battery is used as the thermoelectric conversion element 530, water is used as the high-temperature heat medium 300, and saturated high-temperature steam 302 is generated by the fuel cell 101 generating saturated steam at 160 ° C. FIG. 3 shows the relationship between the partition wall temperature in the heat transfer section 501 and the distance from the saturated steam inlet. In FIG. 3, the horizontal axis represents the partition wall temperature, and the vertical axis represents the distance from the saturated steam inlet of the high temperature heat transfer section 501 downward. From Fig. 3, as the distance from the entrance increases,
The heat transfer coefficient decreased due to the increased thickness of the condensed water layer adhering to the partition walls, and the partition wall temperature decreased, but the rate was small, and the temperature decrease was suppressed to 3 ° C. or less even at the position 2 m from the inlet. Therefore, according to this example, it was confirmed that the temperature decrease of the high temperature heat medium can be suppressed without using the power required for transporting the heat medium. Although trichlorofluoromethane was used as the low temperature heat transfer medium, the low temperature heat transfer part 502 was in the state of pool boiling because the low temperature heat transfer part 502 was in the state of pool boiling.
The temperature of the partition wall was constant regardless of the temperature from the inlet of the power generation section 500. From this, the effect of this example was confirmed.

[0026]

As described above, according to the present invention, it is possible to suppress the temperature drop of the high temperature heat medium and the temperature rise of the low temperature heat medium in the power generation section, and it is possible to reduce the power required to convey each heat medium. Therefore, a thermoelectric conversion device with high conversion efficiency can be provided.

[Brief description of drawings]

FIG. 1 is a configuration explanatory view showing a first embodiment of the present invention.

FIG. 2 is a structural explanatory view showing a second embodiment of the present invention.

FIG. 3 is a characteristic diagram illustrating effects of the second embodiment of the present invention.

FIG. 4 is a structural explanatory view showing a conventional thermoelectric conversion device.

FIG. 5 is a characteristic diagram showing temperature distributions of a high temperature heat medium and a low temperature heat medium according to a conventional thermoelectric conversion device.

[Explanation of symbols]

10 ... Heat supply device, 20 ... High temperature heat medium circulation pipe line, 30 ...
High temperature heat medium, 40 ... High temperature heat medium circulation pump, 50 ... Power generation section, 51 ... High temperature heat transfer section, 52 ... Low temperature heat transfer section, 53 ...
Thermoelectric conversion element, 60 ... Radiating device, 70 ... Low temperature heat medium circulation line, 80 ... Low temperature heat medium, 90 ... Low temperature heat medium circulation pump, 100 ... Boiling type heat supply device, 200 ... High temperature heat medium circulation line, 300 … High temperature heat medium, 301… High temperature saturated steam,
302 ... High temperature liquid, 500 ... Power generation part, 501 ... High temperature heat transfer part, 502 ... Low temperature heat transfer part, 530 ... Thermoelectric conversion element,
600 ... Condensing type heat dissipation device, 700 ... Low temperature heat medium circulation pipe, 800 ... Low temperature heat medium, 801, ... Low temperature liquid, 802 ...
Low temperature saturated steam.

Claims (5)

[Claims] 1. A heat supply device, a high-temperature heat medium circulation pipe for circulating a high-temperature heat medium heated by the heat supply device, a heat dissipation device, and a low temperature for circulating a low-temperature heat medium cooled by the heat dissipation device. A thermoelectric generator including a heat medium circulation pipe, a high temperature heat transfer part, a low temperature heat transfer part, and a power generation part including a thermoelectric conversion element installed in contact between the high temperature heat transfer part and the low temperature heat transfer part. In the conversion device, a boiling type heat supply device is used as the heat supply device. 2. The thermoelectric conversion device according to claim 1,
The liquid level of the high temperature heat medium of the liquid generated by the condensation of the high temperature heat medium of the saturated vapor in the high temperature heat transfer unit and the liquid level of the high temperature heat medium of the liquid in the boiling heat supply device are equal to each other. A thermoelectric conversion device, characterized in that a boiling heat supply device is installed. 3. The thermoelectric conversion device according to claim 1, wherein
A thermoelectric conversion device, wherein a fuel cell and a heat exchange device for transferring heat generated in the fuel cell to the high-temperature heat medium of the liquid are used as the boiling heat supply device. 4. A heat supply device, a high-temperature heat medium circulation conduit for circulating a high-temperature heat medium heated by the heat supply device, a heat dissipation device, and a low temperature for circulating a low-temperature heat medium cooled by the heat dissipation device. A thermoelectric generator including a heat medium circulation pipe, a high temperature heat transfer part, a low temperature heat transfer part, and a power generation part including a thermoelectric conversion element installed in contact between the high temperature heat transfer part and the low temperature heat transfer part. A thermoelectric conversion device, wherein a condensing type heat dissipation device is used as the heat dissipation device. 5. The thermoelectric conversion device according to claim 4,
The condensing type heat dissipation device is installed at a height at which the liquid level of the liquid low temperature heat medium filled in the low temperature heat transfer part and the liquid level of the liquid low temperature heat medium in the condensing type heat dissipation device are equal. A thermoelectric conversion device.