JP2014081088A - Heat exchanging apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat exchange device which can be operated constantly without using electric energy using geothermal heat or water temperature as a heat source.
SOLUTION: A triple pipe 10 composed of an outer pipe 1, an inner pipe 2 and a central pipe 3 extending vertically is provided. The triple pipe 10 has a lower part submerged in the ground and an upper part exposed to the ground. The outer pipe 1 has a heat insulating property, and upper and lower ends are closed, and a lower heat exchange section 11 and an upper heat exchange for exchanging heat inside and outside the outer pipe 1 respectively in the underground portion and the ground portion. The inner tube 2 has a heat insulating property and is located inside the outer tube 1 and communicates with the outer tube 1 at the upper and lower ends. It is located inside the inner tube 2 and penetrates the outer tube 1 up and down. The outer tube 1 and the inner tube 2 are sealed with a working medium M, and the central tube 3 has a bottom from the top. Auxiliary working medium W is flowing toward.
[Selection] Figure 1

Description

  The present invention relates to a heat exchange device that performs heat exchange via a working medium using geothermal heat or water temperature as a heat source.

  The underground depth of 6 m or less is substantially constant regardless of the ground temperature. 2. Description of the Related Art Conventionally, many air conditioners that perform indoor air conditioning using a heat source (geothermal) at a substantially constant temperature have been proposed. The invention shown in Patent Document 1 is also an example thereof, including a heat pump that uses water in the underground water reservoir as a heat source, heat exchange between this water and water in a closed circuit that circulates in various places in the room, Heat is exchanged between water in the closed circuit and room air in heat exchangers at various locations in the room. Since the geothermal temperature is higher than the winter room temperature and lower than the summer room temperature, the air flowing through the heat exchanger is warmed above the room temperature in the winter, and the air flowing through the heat exchanger is heated in the summer. It is cooled below the room temperature. Since such an air conditioner uses natural energy as a heat source, the environmental load is small and the energy saving effect is high.

JP-A-2005-164160

  However, although the invention of Document 1 is supposed to cause natural convection of air, it is difficult to constantly circulate water, which is a working medium of a heat pump, only by natural convection, and a pump for that purpose is required. . In addition to the invention of Document 1, heat exchangers such as this type of air conditioner conventionally have a pump for circulating the working medium. Especially in summer, the room temperature is higher than the geothermal temperature. Therefore, the working medium was hot at the upper part (inside the room) and cold at the lower part (the underground side), and natural convection did not occur, and a pump was indispensable. And since electric energy is consumed for the drive of a pump, it was a problem that the energy-saving effect by using natural energy fell.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a heat exchange device that can be operated constantly without using electric energy using geothermal heat or water temperature as a heat source.

  The present invention comprises a triple pipe consisting of an outer pipe, an inner pipe and a central pipe extending vertically, and the lower part of the triple pipe is submerged in the ground or water, the upper part is exposed on the ground or water, The pipe is heat-insulating, the upper and lower ends are closed, and a lower heat exchanging section for exchanging heat inside and outside the outer pipe, respectively, in the underground part or the underwater part and the ground part or the water part, and It has an upper heat exchanging part, the inner pipe has heat insulation, is located inside the outer pipe, communicates with the outer pipe at the upper and lower ends, and the central pipe is the inner pipe It is located inside the pipe and penetrates the outer pipe up and down, the working medium is sealed in the outer pipe and the inner pipe, and the auxiliary working medium flows from the bottom to the top in the center pipe. It is characterized by. The “triple tube comprising an outer tube, an inner tube, and a central tube extending vertically” includes not only one in which each tube extends in the vertical direction but also one that inclines within a range in which the fluid in each tube flows by gravity.

  According to the heat exchanging apparatus of the present invention configured as described above, for example, when indoor air conditioning is performed using geothermal heat, the upper (indoor side) working medium is cooled by the room temperature (from the working medium in winter). The heat is released into the room), and the density increases and moves downward between the outer tube and the inner tube by gravity. Then, the lower (underground) working medium is warmed by the geothermal temperature (heat absorption from the underground to the working medium), the density is reduced, and the inside of the inner pipe moves upward. Thereby, a convection arises in a working medium, it circulates, and it can perform heat exchange constantly. In addition, when using tap water as an auxiliary working medium that flows inside the central pipe, tap water can be warmed by passing through the ground below the lower end of the outer pipe, so that tap water having a temperature higher than usual can be supplied. . On the other hand, in the summer, the upper (indoor side) working medium is warmed by the room temperature (absorbing heat from the room to the working medium), the density decreases, and moves upward between the outer pipe and the inner pipe. Further, the auxiliary working medium flowing inside the central tube is cooled by passing through the ground below the lower end of the outer tube. Then, the working medium at the upper end is cooled by the auxiliary working medium (heat radiation from the working medium to the auxiliary working medium), the density increases, and the inside of the inner tube moves downward due to gravity. Thereby, a convection arises in a working medium, it circulates, and it can perform heat exchange constantly. When tap water is used as the auxiliary working medium, the tap water can be warmed to near the room temperature by the working medium, so that tap water having a temperature higher than usual can be supplied. In addition to being used for air conditioning, it is also possible to generate power using the temperature difference between the ground and the ground. Further, in the case of using the temperature difference between the underwater and the surface temperature on the water in the sea or the lake, the same operation can be performed.

  According to the present invention, by interposing an auxiliary working medium during heat exchange, it becomes possible to operate constantly without using electric energy. Further, when tap water is used as the auxiliary working medium, the tap water is warmed in the process of heat exchange, so that energy required for hot water supply can be reduced.

1 is an overall view of a first embodiment of a heat exchange device of the present invention. It is explanatory drawing of operation | movement in winter. It is explanatory drawing of operation | movement in the summer. It is explanatory drawing which shows the calculation conditions of the numerical analysis of the output of a heat exchange apparatus. It is a figure which shows the calculation result of temperature distribution, (a) is a winter season, (b) is a summer season. It is a graph which shows the calculation result of the time passage of an output, (a) is a winter season, (b) is a summer season. It is a general view of 2nd embodiment of the heat exchange apparatus of this invention. It is a general view of 3rd embodiment of the heat exchange apparatus of this invention. It is a general view of 4th embodiment of the heat exchange apparatus of this invention. It is a general view of 5th embodiment of the heat exchange apparatus of this invention.

  A specific configuration of the heat exchange device of the present invention will be described with reference to the drawings. As shown in FIG. 1, the first embodiment of the heat exchanging apparatus is for performing indoor air conditioning using geothermal heat, and includes a triple pipe 10 including an outer pipe 1, an inner pipe 2, and a central pipe 3. . The outer tube 1, the inner tube 2 and the central tube 3 are all circular tubes extending in the vertical direction.

  The outer tube 1 is made of vinyl chloride and has heat insulation properties. The upper and lower ends are closed, and the inside is a sealed space. And as for the outer tube | pipe 1, the lower part is embed | buried under the ground and the upper part is exposed to the ground (indoor space S in a building). In addition, FIG. 1 is a schematic diagram, and the length of the portion buried in the ground and the portion exposed on the ground need not be the same. As described above, since it is in the ground of 6 m or less that becomes a substantially constant temperature regardless of the temperature on the ground, the length of the portion buried in the ground is preferably 6 m or more. On the other hand, the length of the portion exposed on the ground can be freely set according to the size of the building. And the lower side heat exchange part 11 and the upper side heat exchange part 12 which heat-exchange inside and outside of the outer pipe | tube 1 are provided in the underground part and ground part of the outer pipe | tube 1, respectively. In either case, a part of the outer tube 1 is replaced with an aluminum tube material having a high thermal conductivity. Thereby, the outer tube 1 can exchange heat inside and outside only in the lower heat exchange unit 11 and the upper heat exchange unit 12.

  The inner tube 2 is made of the same vinyl chloride as the outer tube 1 and has heat insulation properties. The inner tube 2 has a smaller diameter than the outer tube 1 and is provided inside the outer tube 1. The upper and lower ends of the inner tube 2 are open, shorter than the outer tube 1, and communicate with the outer tube 1 at the upper and lower ends.

  Further, the center tube 3 is made of aluminum having a high thermal conductivity, has a smaller diameter than the inner tube 2, is provided inside the inner tube 2, and penetrates the outer tube 1 up and down.

  The outer tube 1 and the inner tube 2 are sealed with water as the working medium M. Further, a water supply pipe 4 is connected to the lower end of the center pipe 3, and the tap water flows as an auxiliary working medium W from the bottom to the top inside the center pipe 3. Further, a hot water supply pipe 5 is connected to the upper end of the center pipe 3, and the hot water supply pipe 5 is connected to a hot water supply tank 6. The water supply pipe 4 and the hot water supply pipe 5 are steel pipes that are common as water pipes. Further, the water supply pipe 4 inevitably passes through a place deeper in the ground than the lower end of the outer pipe 1.

  Next, operation | movement of 1st embodiment of the heat exchange apparatus comprised in this way is demonstrated. 2 and 3, the temperature levels of the working medium M and the auxiliary working medium W are represented by color shades, where the high temperature portion is light and the low temperature portion is dark. First, in winter, geothermal temperature> tap water temperature> indoor temperature. Therefore, as shown in FIG. 2, the upper (indoor side) working medium M is cooled by the room temperature via the upper heat exchange unit 12. This means that heat is dissipated from the working medium M to the indoor space S, and the indoor temperature rises. Then, the density of the upper working medium M increases, and moves downward between the outer tube 1 and the inner tube 2 by gravity. Then, the working medium M having a room temperature that has moved downward is warmed by the geothermal temperature via the lower heat exchange unit 11. This means that the working medium M absorbs heat from the ground. Then, the density of the lower working medium M decreases, and the inside of the inner tube 2 moves upward. As a result, the working medium M has a convection that descends between the outer tube 1 and the inner tube 2 and rises inside the inner tube 2, so heat is absorbed in the ground and radiated in the indoor space S. Exchanges can be made permanently. Further, the tap water of the auxiliary working medium W flowing inside the center pipe 3 is warmed by the geothermal temperature by passing through a deeper place in the ground than the lower end of the outer pipe 1. Therefore, the hot water tank 6 can store tap water having a temperature higher than usual.

  On the other hand, in summer, geothermal temperature <tap water temperature <room temperature. Therefore, as shown in FIG. 3, the upper (indoor side) working medium M is warmed by the room temperature via the upper heat exchange unit 12. This means that heat is absorbed from the indoor space S to the working medium M, and the indoor temperature decreases. Then, the density of the upper working medium M becomes smaller and moves upward between the outer tube 1 and the inner tube 2. Further, the auxiliary working medium W flowing inside the center tube 3 is cooled by the geothermal temperature by passing through a deeper place in the ground than the lower end of the outer tube 1. This means that heat is radiated from the auxiliary working medium W into the ground. Then, the working medium M having the room temperature moved to the upper end is cooled by the auxiliary working medium W. This means that heat is radiated from the working medium M to the auxiliary working medium W. Then, the density of the working medium M at the upper end increases, and the inside of the inner tube 2 moves downward due to gravity. As a result, the working medium M rises between the outer pipe 1 and the inner pipe 2 and descends inside the inner pipe 2, so that heat is absorbed in the indoor space S and the auxiliary working medium W is passed through. Heat exchange that radiates heat in the ground can be performed constantly. The tap water of the auxiliary working medium W is warmed to near the room temperature by the working medium M. Therefore, the hot water tank 6 can store tap water having a temperature higher than usual.

  Thus, according to the first embodiment of the heat exchange device, it is possible to perform air conditioning so that the room temperature is brought close to the geothermal temperature by operating constantly without using electric energy. In particular, in the summer when the room temperature is higher than the geothermal temperature, convection does not occur only with the working medium M, but convection can be caused by interposing the tap water of the auxiliary working medium W during heat exchange. ing. Note that the auxiliary working medium W does not always need to flow, and it is only necessary that the working medium M at the upper end can be cooled and lowered when the temperature of the working medium M becomes high. Therefore, in a house or a factory where a geothermal air conditioner composed of this heat exchange device is installed, operation is possible if there is an intermittent flow due to the use of water in connection with normal life and business. Further, since the tap water of the auxiliary working medium W is warmed in the process of heat exchange, the energy required when the tap water in the hot water supply tank 6 is heated and used can be reduced.

Subsequently, the output of the heat exchange device configured as described above is obtained. First, the amount of heat transferred when air is used as the working medium and when water is used is compared. When air is used as a working medium, the amount of heat transferred per unit time due to air movement is expressed by the following equation.
Here, assuming that the underground temperature is 18 ° C. and the outside air temperature is 5 ° C., and the air is circulated through the pipe having a diameter of 10 cm at a flow rate of 5 m / s, the amount of heat transferred per unit time is expressed by the following equation.

On the other hand, the amount of heat transfer per unit time due to the movement of water when water is used as the working medium is expressed by the following equation.
Here, assuming that the underground temperature is 18 ° C. and the outside air temperature is 5 ° C., and water is circulated through the pipe having a diameter of 10 cm at a flow rate of 0.01 m / s, the amount of heat transferred per unit time is expressed by the following equation.

  Thus, comparing air and water as the working medium for heat exchange shows that water has a high heat transport capability even at low speed. However, the above calculation is higher than the actual value because it does not take into account the effects of heat conduction or convection in the pipe wall, underground, indoors, etc., or loss due to pipe piping.

  Next, numerical analysis was performed under more realistic conditions. In the heat exchange device of the present invention, the water of the working medium naturally convects in the pipe. In the numerical analysis of the natural convection, the continuous equation, the Navier-Stokes equation and the thermal energy conservation equation are differentiated to obtain the SOLA. The method was used. Note that the influence of density change due to temperature was obtained by the Businessesque approximation. As shown in FIG. 4, the assumed triple tube is composed of an outer tube, an inner tube, and a central tube, and each tube is a concentric circular tube extending in the vertical direction. The outer tube is made of a heat insulating material, and has a diameter of 0.44 m, a thickness of 20 mm, a height of 5 m, an underground portion of 3 m, and a ground portion of 2 m. The range from the lower end to the upper side 1 m is the lower heat exchange part, and the range from the ground surface to the upper side 1 m is the upper heat exchange part. The inner tube is made of a heat insulating material and has a diameter of 0.32 m and a thickness of 20 mm. The central tube is made of aluminum and has a diameter of 0.16 m and a thickness of 20 mm. The calculation area is the entire inside of the outer tube, and based on a cylindrical coordinate system with the central axis of each tube as the coordinate axis, the calculation grid width is 0.01 m in the radial direction and 0.0125 m in the height direction, Calculations were performed with a 20 × 400 grid. As described above, the length of the portion of the outer pipe that is originally buried in the ground is preferably 6 m or longer, but here it is 3 m in order to shorten the calculation time.

  First, assuming winter, the upper heat exchange part that exchanges heat with the indoor space is 10 ° C., and the lower heat exchange part that exchanges heat with the ground is 18 ° C. As a result, the temperature distribution as shown in FIG. 5A was obtained, and it was confirmed that water in the working medium descends between the outer tube and the inner tube, and convection occurs in the inner tube. FIG. 6A is a graph in which time is plotted on the horizontal axis and output is plotted on the vertical axis, and it can be seen that the output becomes steady over time.

  Next, assuming summer, the upper heat exchanging part for exchanging heat with the indoor space is set to 30 ° C., the lower heat exchanging part for exchanging heat with the ground is set to 18 ° C., and tap water which is an auxiliary working medium in the central pipe The calculation was performed at a flow rate of 0.01 m / s (the flow rate of the auxiliary working medium is about 5 L / min). As a result, the temperature distribution as shown in FIG. 5B was obtained, and it was confirmed that the convection in which the water of the working medium rose between the outer tube and the inner tube and descended inside the inner tube. FIG. 6B is a graph in which time is plotted on the horizontal axis and output is plotted on the vertical axis, and it can be seen that the output becomes steady over time.

  From the above calculation results, it was confirmed that the output equivalent to the amount of moving heat of air (0.6 kW) can be obtained with only the working medium in winter. In both winter and summer, it is confirmed that the output is in a steady state over time, and it is possible to perform air conditioning by constantly circulating the working medium without using electric energy. It was done. In winter, the output in a steady state is about 550 W. However, if the length of the portion embedded in the ground of the outer pipe is made longer, the output will be further increased. In summer, the output in a steady state is about 530 W. However, if the length of the ground portion of the outer pipe (the length by which the working medium absorbs heat and rises) is made longer, the output is further increased. The larger the difference between the underground temperature and the ground temperature, the greater the output (there is no output if there is no temperature difference). Furthermore, the larger the flow rate of the auxiliary working medium, the greater the output. In other words, in summer, the working medium is cooled by the auxiliary working medium as described above. Therefore, the larger the flow rate of the auxiliary working medium, the larger the heat exchange amount, and the larger the output. On the other hand, in the winter season, an auxiliary working medium is ideally not necessary, but in reality, when the temperature of the indoor space decreases and the temperature of the working medium also decreases, the working medium is not obtained only in the lower heat exchange section in the ground. Does not rise to underground temperature. Here, when the auxiliary working medium circulates and is close to the ground temperature, the working medium can also absorb heat from the auxiliary working medium and raise the temperature (that is, the auxiliary working medium is also heated with the geothermal heat). The output becomes larger.

  As described above, the first embodiment of the heat exchange device of the present invention is characterized in that it can be operated constantly without using electric energy, but in summer, water is used for a long time for some reason. Otherwise, the upper working medium M cannot be cooled and the working medium M will not circulate. Thus, in preparation for such a case, the second embodiment of the heat exchange device is provided with a circulation pump 7 for circulating the auxiliary working medium W. As shown in FIG. 7, the second embodiment includes a triple pipe 10 (outer pipe 1, inner pipe 2, central pipe 3), water supply pipe 4, hot water supply pipe 5, and hot water supply tank 6, as in the first embodiment. Have. A difference from the first embodiment is that a return pipe 8 that connects the hot water supply tank 6 and the water supply pipe 4 is provided, and a circulation pump 7 is provided in the middle of the return pipe 8. By driving the circulation pump 7, the tap water of the auxiliary working medium W returns from the hot water supply tank 6 to the hot water supply tank 6 via the return pipe 8, the water supply pipe 4, the central pipe 3, and the hot water supply pipe 5. Circulate.

  Next, operation | movement of 2nd embodiment of the heat exchange apparatus comprised in this way is demonstrated. The second embodiment operates in the same manner as the first embodiment when water is used in winter and summer. When the water supply is not used in summer, first, the upper (indoor side) working medium M is warmed by the room temperature via the upper heat exchange unit 12. This means that heat is absorbed from the indoor space S to the working medium M, and the indoor temperature decreases. Then, the density of the upper working medium M becomes smaller and moves upward between the outer tube 1 and the inner tube 2. Therefore, the circulation pump 7 is driven to circulate the auxiliary working medium W. Then, the auxiliary working medium W in the hot water supply tank 6 is cooled by the geothermal temperature by passing through the water supply pipe 4 that is located deeper in the ground than the lower end of the outer pipe 1. This means that heat is radiated from the auxiliary working medium W into the ground. Then, the working medium M having the room temperature moved to the upper end is cooled by the auxiliary working medium W. This means that heat is radiated from the working medium M to the auxiliary working medium W. Then, the density of the working medium M at the upper end increases, and the inside of the inner tube 2 moves downward due to gravity. As a result, as in the first embodiment, the working medium M has a convection that rises between the outer tube 1 and the inner tube 2 and descends inside the inner tube 2, and therefore absorbs heat in the indoor space S. The heat exchange of radiating heat in the ground via the auxiliary working medium W can be performed constantly. The tap water of the auxiliary working medium W is warmed to near the room temperature by the working medium M. Therefore, the temperature of the tap water in the hot water supply tank 6 remains higher than usual.

  Thus, according to the second embodiment of the heat exchange device, in a normal state where water supply is used, air conditioning is performed by operating constantly without using electric energy, as in the first embodiment. be able to. And by providing the circulation pump 7, even when a water supply is not utilized in summer, it can be operated constantly. The circulation pump 7 does not need to be continuously driven. Since it suffices if the temperature of the working medium M at the upper end can be lowered and lowered, it can be handled by intermittent driving, and the consumption of electric energy is small. Alternatively, the temperature of the working medium M may be detected and automatically driven.

  Next, 3rd embodiment of the heat exchange apparatus of this invention is described based on FIG. In the third embodiment, not the tap water but the ground water is used as the auxiliary working medium W. As shown in FIG. 8, the third embodiment has a triple pipe 10 (outer pipe 1, inner pipe 2, central pipe 3), hot water supply pipe 5, and hot water supply tank 6, as in the first embodiment. . And the difference from the first embodiment is that one end of the water supply pipe 4 a is connected to the lower end of the center pipe 3, the other end of the water supply pipe 4 a reaches the groundwater source H, and in the middle of the hot water supply pipe 5. A pumping pump 9 for pumping up groundwater is provided. According to the third embodiment of the heat exchange device configured as described above, in the winter season, the operation is the same as in the winter season of the first embodiment. And in the summer, by driving the pumping pump 9, the groundwater of the auxiliary working medium W flows from the bottom to the top in the central pipe 3, and operates in the same way as in the summer in the first embodiment.

  As described above, according to the third embodiment of the heat exchange device, in the winter season, it is possible to perform air conditioning by operating constantly without using electric energy as in the first embodiment. In summer, the pump 9 can be driven constantly by driving the pumping pump 9. The pumping pump 9 need not be driven continuously. Since it suffices if the temperature of the working medium M at the upper end can be lowered and lowered, it can be handled by intermittent driving, and the consumption of electric energy is small. Alternatively, the temperature of the working medium M may be detected and automatically driven.

  Next, 4th embodiment of the heat exchange apparatus of this invention is described based on FIG. In the fourth embodiment, a structure for heating the auxiliary working medium W using solar heat is added to the second embodiment. As shown in FIG. 9, the fourth embodiment is similar to the second embodiment in the triple pipe 10 (outer pipe 1, inner pipe 2, central pipe 3), water supply pipe 4, hot water supply pipe 5, hot water supply tank 6, A return pipe 8 and a circulation pump 7 are provided. The difference from the second embodiment is that the hot water supply pipe 5 passes on the roof of the building and is exposed to sunlight, and the hot water supply tank 6 is installed at a high position (on the roof). And a bypass pipe 71 that bypasses the circulation pump 7, and a check valve 72 is provided in the bypass pipe 71. According to the fourth embodiment of the heat exchange device configured as described above, when the water supply is used in winter and summer, it operates in the same manner as in the first embodiment. And even if it is a case where a water supply is not utilized in the summer, the auxiliary | assistant working medium W can be circulated by solar heat and heat exchange can be performed during the daytime. That is, the auxiliary working medium W in the hot water supply pipe 5 on the roof is heated by solar heat (about 70 ° C.), and the hot auxiliary working medium W is stored in the hot water supply tank 6. The auxiliary working medium W in the hot water supply tank 6 is lowered in temperature and increased in density by heat radiation, and descends from the hot water supply tank 6 at a high position through the return pipe 8. Further, the auxiliary working medium W circulates back to the water supply pipe 4 through the bypass pipe 71 and the check valve 72. However, when the entire auxiliary working medium W in the hot water supply tank 6 becomes high temperature, the circulation force is lost. In this case, the circulation pump 7 is driven.

  Thus, according to the fourth embodiment of the heat exchange device, when water supply is used in winter and summer, air conditioning can be performed by operating constantly without using electric energy. And even if it is a case where a water supply is not utilized in the summer, the auxiliary | assistant working medium W is circulated with a solar heat, and it can drive | operate constantly. Since the circulation pump 7 only needs to be driven when the entire auxiliary working medium W in the hot water supply tank 6 becomes high temperature, the frequency of use of the circulation pump 7 can be reduced as compared with the second embodiment. Further, when the hot water in the hot water supply tank 6 is not used, the hot water tank 6 has a structure that can easily radiate heat, and the temperature of the hot water is lowered to the outside air temperature. Without using the auxiliary working medium W can be circulated constantly only by solar heat.

  Next, 5th embodiment of the heat exchange apparatus of this invention is described based on FIG. In the fifth embodiment, the auxiliary working medium W is circulated using the water level difference of the irrigation channel. As shown in FIG. 10, the fifth embodiment has a triple tube 10 (an outer tube 1, an inner tube 2, and a central tube 3) as in the first embodiment. The difference from the first embodiment is that one end of the water supply pipe 4b is connected to the lower end of the center pipe 3, and the other end of the water supply pipe 4b is submerged in the water of the water supply side water channel C1. One end of the drain pipe 5b is connected to the upper end, and the other end of the drain pipe 5b is submerged in the water of the drain side water channel C2. In addition, the water surface of the water supply side channel C1 is at a higher position than the water surface of the drain side channel C2. According to the fifth embodiment of the heat exchange device configured as described above, the auxiliary working medium W flows from the water supply side water channel C1 to the water discharge side water channel C2 by the principle of siphon. In winter, the operation is the same as in the winter of the first embodiment. On the other hand, since the auxiliary working medium W flows from the bottom to the top in the central tube 3 in the summer, the operation is the same as in the summer in the first embodiment. As a condition for the auxiliary working medium W to flow from the water supply side channel C1 to the drain side channel C2, it is necessary that there is a water level difference sufficient to generate a water pressure exceeding the pipe frictional resistance.

  Thus, according to the fifth embodiment of the heat exchanging device, the water level difference between the water supply side water channel C1 and the water discharge side water channel C2 serves as a substitute for the pump, and is constant without using electric energy in both winter and summer. It can be operated and air-conditioning can be performed. The heat exchange apparatus of this embodiment is expected to be used mainly for air conditioning in a greenhouse or the like.

  The present invention is not limited to the above embodiment. For example, regarding the material constituting each part, the outer tube and the inner tube may be anything as long as they have heat insulation properties. The center tube and the heat exchanging section may be anything as long as they can efficiently exchange heat, but the output can be further improved by using a material having high thermal conductivity. Furthermore, if fins or the like are installed on the surface where heat exchange is performed, the amount of heat transfer is increased, and the output can be further improved. In addition, the triple pipe is not limited to the one extending in the vertical direction, and may be inclined within a range in which the fluid in each pipe flows by gravity. Furthermore, the working medium may be a fluid that changes in density with temperature. For example, an antifreeze solution may be used in a cold region. In addition, although the liquid is more efficient, the liquid can be operated even in the environment where the liquid cannot be used. Furthermore, as for the auxiliary working medium, various fluids (liquid or gas) other than water that can move heat can be used if there is no purpose of using hot water. In addition to the use for air conditioning as in each of the embodiments described above, it is also possible to generate power using the temperature difference between the ground and the ground. Examples of the power generation method include a method of generating power by the Seebeck effect by attaching a Peltier element to the heat transfer surface of the heat exchange device, and a method of generating power by evaporating a low-boiling substance and rotating a turbine. The pump may be operated by the generated electricity. Further, in the case of using the temperature difference between the underwater and the surface temperature on the water in the sea or the lake, the same operation can be performed.

DESCRIPTION OF SYMBOLS 1 Outer tube 2 Inner tube 3 Center tube 10 Triple tube 11 Lower heat exchange part 12 Upper heat exchange part M Working medium W Auxiliary working medium

Claims (1)

Equipped with a triple pipe consisting of an outer pipe, an inner pipe and a central pipe extending vertically
The triple pipe is submerged in the ground or water, and the upper part is exposed on the ground or water,
The outer pipe has heat insulating properties, the upper and lower ends are closed, and a lower heat exchanging section for exchanging heat inside and outside the outer pipe to the underground part or the underwater part and the ground part or the water part, respectively. And an upper heat exchange part,
The inner tube has heat insulation, is located inside the outer tube, and communicates with the outer tube at the upper and lower ends.
The central tube is located inside the inner tube and penetrates the outer tube up and down,
The outer tube and the inner tube are sealed with a working medium,
A heat exchange device, wherein an auxiliary working medium flows in the center tube from bottom to top.