Heat exchange device

Abstract

To provide a heat exchange device that can be reduced in size and can improve the energy consumption efficiency.SOLUTION: A heat exchange device comprises a nanoporous body, a highly-thermally-conductive porous portion, a stress applying portion, and a housing portion. The nanoporous body has elasticity, can contract to release a medium, and can expand to adsorb the medium. The highly-thermally-conductive porous portion is adjacent to the surface of the nanoporous body, has selectivity for not passing through the nanoporous body but allowing the medium to pass therethrough, and has higher thermal conductivity than the nanoporous body. The stress applying portion applies a stress to the nanoporous body. The housing portion houses the nanoporous body, the highly-thermally-conductive porous portion, and the medium.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a heat exchanger.

Background Art

[0002] Conventionally, heat exchangers that heat or cool a target (space or object) by transferring heat have been widely used. For example, Patent Document 1 below discloses an adsorption heat pump (desiccant air conditioner) that includes a high heat source that vaporizes water as a medium, a low heat source that condenses the vaporized water, and a desiccant (drying material) that collects water. In such an adsorption heat pump, generally, a porous body such as silica gel or zeolite is adopted as the adsorbent used for the desiccant.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a conventional adsorption heat pump (desiccant air conditioner), the moving speed of the fluid refrigerant in the porous body is low. For this reason, when the refrigerant molecules evaporate (i.e., absorb heat), the evaporation speed of the refrigerant molecules is low, and it is difficult to obtain a sufficient amount of heat absorption per unit time. In order to promote the evaporation of the refrigerant molecules, a method of raising the temperature of the porous body can be considered, but this method requires a heater for heat input, leading to an increase in the size of the device. In addition, energy is required to operate the heater, resulting in a decrease in energy consumption efficiency.

[0005] The present invention has been made in view of such circumstances, and an object thereof is to provide a heat exchanger that can be miniaturized and can improve energy consumption efficiency.

Means for Solving the Problem

[0006] The heat exchanger according to one aspect of the present invention includes a nanoporous body, a high thermal conductivity porous portion, a stress applying portion, and a housing portion. The nanoporous body has elasticity, can contract to desorb the medium, and can expand to adsorb the medium. The high thermal conductivity porous portion is adjacent to the surface of the nanoporous body, has the selectivity of allowing the medium to permeate without passing through the nanoporous body, and has a higher thermal conductivity than the nanoporous body. The stress applying portion applies stress to the nanoporous body. The housing portion houses the nanoporous body, the high thermal conductivity porous portion, and the medium inside.

Advantages of the Invention

[0007] According to one aspect of the present invention, it is possible to provide a heat exchanger that can be miniaturized and can improve the energy consumption efficiency.

Brief Description of the Drawings

[0008]

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MODE FOR CARRYING OUT THE INVENTION

[0009] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the description of the drawings referred to in the following description, the same or similar parts are denoted by the same or similar reference numerals. However, it should be noted that the drawings are schematic, and the relationship between the thickness and the planar dimensions, the ratio of the thicknesses of the respective layers, etc. are different from the actual ones. Therefore, specific thicknesses and dimensions should be determined with reference to the following description. Also, it goes without saying that there are portions where the dimensional relationships and ratios are different between the drawings.

[0010] In the following description, the directions may be described using the terms in the X-axis direction, the Y-axis direction, and the Z-axis direction. The Z-axis direction is the thickness direction of the high thermal conductivity porous portion 23, and is the direction in which stress is applied by the stress applying portion 31. The X-axis direction and the Y-axis direction are directions orthogonal to the thickness direction of the high thermal conductivity porous portion 32. A plane parallel to both the X-axis direction and the Y-axis direction is also referred to as the X-Y plane. The X-axis direction, the Y-axis direction, and the Z-axis direction are orthogonal to each other.

[0011] (Overall configuration example) Figures 1 and 2 are cross-sectional views showing a configuration example of a heat exchanger 100 according to an embodiment of the present invention. Figure 1 shows a state where the stress applying portion 31 does not apply stress to the nanoporous body 20. Figure 2 shows a state where the stress applying portion 31 applies stress to the nanoporous body 20. The arrow Q in Figure 2 schematically indicates the direction of heat transfer. The heat exchanger 100 shown in Figures 1 and 2 is a device that can be applied, for example, to a car air conditioner (cooling) that cools the interior (inside air) of a vehicle.

[0012] The heat exchanger 100 mechanically deforms by applying and releasing stress to the nanoporous body 20 to desorb and adsorb the medium 27. For example, the heat exchanger 100 cools an object (e.g., air) using the latent heat of evaporation generated during desorption of the medium 27. Also, the heat exchanger 100 can heat the air using the waste heat generated during adsorption of the medium 27. The heat exchanger 100 can also mix the cooled air and the heated air to adjust the air to a desired temperature.

[0013] As shown in Figures 1 and 2, the heat exchanger 100 includes a nanoporous body 20, a high heat conduction porous portion 23, a heat conduction portion 29, a stress applying portion 31, and a housing portion 32. The nanoporous body 20 has elasticity, can contract to desorb the medium 27, and can expand to adsorb the medium 27.

[0014] The high heat conduction porous portion 23 is adjacent to the surface of the nanoporous body 20, has the selectivity of allowing the medium 27 to pass through without passing through the nanoporous body 20, and has a higher heat conductivity than the nanoporous body 20. The high heat conduction porous portion 23 constitutes, for example, a nanoporous body pack 2 including the nanoporous body 20.

[0015] The heat conduction part 29 is in direct or indirect contact with the nanoporous body 20 to conduct the heat of the nanoporous body 20. The heat conduction part 29 conducts the heat of the nanoporous body 20 directly or indirectly through the high heat conduction porous part 23 by contacting the nanoporous pack 2, for example.

[0016] The stress applying part 31 performs an operation of applying stress to the nanoporous body 20 to contract the nanoporous body 20 and an operation of releasing the applied stress to expand the nanoporous body 20. The stress applying part 31 applies stress to the nanoporous pack 2 or releases the applied stress, for example.

[0017] The accommodating part 32 accommodates the nanoporous body 20, the high heat conduction porous part 23, and the medium 27 inside. The accommodating part 32 accommodates the nanoporous pack 2, the first press plate 131A and the second press plate 131B which are part of the stress applying part 31, for example. By the first press plate 131A and the second press plate 131B approaching or moving away while sandwiching the nanoporous pack 2 at the contact part 291 which is part of the heat conduction part 29, stress is applied to the nanoporous pack 2 or the applied stress is released.

[0018] By having the above configuration, the heat exchanger 100 can exchange heat with a substance (for example, air) existing outside the accommodating part 32 using the nanoporous body 20 that absorbs or releases heat by adsorption and desorption of the medium 27 as a heat source. Note that the medium 27 that desorbs or adsorbs from the nanoporous body 20 may be referred to as a refrigerant. Also, the vaporized medium may be referred to as a medium vapor, a refrigerant vapor, or a guest molecule. A refrigerant that is a liquid, a gas, or a mixture of a liquid and a gas may be referred to as a fluid refrigerant. A fluid means a liquid, a gas, or a mixture of a liquid and a gas.

[0019] Hereinafter, each part constituting the heat exchanger 100 will be described in more detail. (Nanoporous Pack) FIG. 3 is a perspective view showing a configuration example of the nanoporous body pack 2 according to an embodiment of the present invention. FIG. 4 is a perspective view showing a state in which a plurality of nanoporous body packs 2 according to an embodiment of the present invention are stacked in one direction. As shown in FIG. 3, the nanoporous body pack 2 is composed of a nanoporous body 20 and a high thermal conductivity porous portion 23 that includes the nanoporous body 20. The nanoporous body 20 is covered with the high thermal conductivity porous portion 23, and its surface is in contact with the high thermal conductivity porous portion 23. Thereby, the nanoporous body 20 is thermally connected to the high thermal conductivity porous portion 23.

[0020] As shown in FIGS. 1, 2, and 4, the heat exchange device 100 includes a plurality of nanoporous body packs 2. A plurality of nanoporous body packs 2 are stacked in a direction in which stress is applied by the stress applying portion 31 (for example, the Z-axis direction). For example, a plurality of nanoporous body packs 2 are stacked and arranged between one surface (the upper surface in FIGS. 1 and 2) of the contact portion 291 that is a part of the heat conducting portion 29 and the first press plate 131A that is a part of the stress applying portion 31. Also, a plurality of nanoporous body packs 2 are stacked and arranged between the other surface (the lower surface in FIGS. 1 and 2) of the contact portion 291 and the second press plate 131A that is another part of the stress applying portion 31.

[0021] (1) Nanoporous body The nanoporous body 20 is composed of a structure including a nanoporous material that has elasticity, can contract to desorb the medium 27, and can expand to adsorb the medium 27. For example, the nanoporous body 20 may include a plurality of particles and a binder that binds the plurality of particles to each other, and each of the plurality of particles has a nanoporous structure (that is, has a plurality of nanoporous-level pores). As shown in FIGS. 1 and 2, the nanoporous body 20 is stressed by the stress applying portion 31 (the first press plate 131A and the second press plate 131B), contracts to desorb the medium 27, and freely expands to adsorb the medium 27 when the stress is released.

[0022] Here, "elasticity" means the property that even when stress is externally applied by the stress application part 31 and it contracts, when the stress is released, it can reversibly deform greatly and recover to almost the original shape. The elastic limit of the nanoporous body 20 is designed to be greater than the stress application required to desorb the medium 27. The elastic limit of the nanoporous body 20 is preferably appropriately designed according to the cooling scale and the like of the application target of the heat exchange device 100.

[0023] Also, "nanoporous" means having a plurality of nanopores. Nanopores preferably have a diameter of 0.5 to 100 nm, more preferably a diameter of 0.7 to 50 nm, and even more preferably micropores or mesopores with a diameter of 0.7 to 6 nm. In the IUPAC (International Union of Pure and Applied Chemistry), pores with a diameter of less than 2 nm are defined as micropores, pores with a diameter of 2 to 50 nm are defined as mesopores, and pores with a diameter of more than 50 nm are defined as macropores.

[0024] When the medium 27 adsorbs to the nanoporous body 20, it undergoes a phase change from gas to liquid, and when it desorbs, it either remains in the liquid state or undergoes a phase change from liquid to gas. The density of the medium 27 inside the pores adsorbed on the pore walls of the nanoporous body 20 is in an equilibrium state with vapor at a pressure lower than the saturated vapor pressure. That is, the gas adsorbed on the pore walls of the nanoporous body 20 is in a liquid state at a pressure lower than the saturated vapor pressure.

[0025] When stress is applied to the nanoporous body 20, the pores of the nanoporous body 20 contract, and the medium 27 adsorbed on the pore walls desorbs. At this time, the medium 27 adsorbed with the liquid density is released to the outside of the nanoporous body 20 as a liquid or a gas. The heat exchange device 100 can cool the target (for example, air) by using the latent heat of evaporation during this desorption as cooling heat.

[0026] When the stress applied to the nanoporous body 20 is released, the nanoporous body 20 freely expands, the pores return to their original size, and the medium 27 is adsorbed again. As described above, when the medium 27 is adsorbed onto the nanoporous body 20, a phase change occurs from a gas to a liquid, generating latent heat of condensation. The heat exchange device 100 can utilize this latent heat of condensation during adsorption as heat.

[0027] Examples of the material of the nanoporous body include graphene mesosponge (GMS) and zeolite template carbon (ZTC). Both GMS and ZTC are composed of a single-layer graphene skeleton and have the porosity and elastic properties necessary for the desorption and adsorption of a fluid refrigerant.

[0028] GMS is a sponge-like mesoporous body in which most of the pore walls are composed of single-layer graphene and which has micro pores of about 6 nm in size. It has an extremely high BET specific surface area (about 2000 m 2 / g), comparable to that of activated carbon. On the other hand, unlike activated carbon and carbon black, it contains almost no graphene ends that cause corrosion, and thus has excellent corrosion resistance (oxidation resistance). Also, due to the property of graphene being flexible and tough, GMS is excellent in flexibility and elasticity and can reversibly elastically deform until the pore diameter becomes from about 5.8 nm to about 0.7 nm. The manufacturing method of GMS is described in Nishihara, H. et al., Advanced Functional Materials, Vol. 26, 2016, 6418 - 6427.

[0029] ZTC is composed of a single-layer graphene sheet. Also, uniform pores (diameter about 1.2 nm) are regularly arranged three-dimensionally and are interconnected, having an extremely high BET specific surface area and pore volume (maximum BET specific surface area of 4100 m 2 / g and a pore volume of 1.8 cc / g). Regarding the manufacturing method of ZTC, it is described in Nishihara, H. et al., Chemistry - European Journal 15, 5355 (2009), etc.

[0030] In the present invention, the material of the nanoporous body is not limited to GMS or ZTC. As long as the material of the nanoporous body has elasticity, can shrink to desorb the medium 27, and can expand to adsorb the medium 27, other materials may be used. As such an example, carbon mesosponge (CMS; Carbon MesoSponge) having spherical mesopores can be mentioned.

[0031] (2) High - thermal - conductivity porous part The high - thermal - conductivity porous part 23 is adjacent to the surface of the nanoporous body 20, has the selectivity of allowing the medium 27 to permeate without passing through the nanoporous body 20, and has a higher thermal conductivity than the nanoporous body 20. By being adjacent to the surface of the nanoporous body 20, the high - thermal - conductivity porous part 23 can be thermally connected to the nanoporous body 20. Also, as shown in FIGS. 1 to 4, the high - thermal - conductivity porous part 23 covers the nanoporous body 20 to form the nanoporous body pack 2. Thereby, the high - thermal - conductivity porous part 23 can support the nanoporous body 20 from the side and suppress the collapse of the shape of the nanoporous body 20.

[0032] The high - thermal - conductivity porous part 23 has holes (openings) that expose the surface of the nanoporous body 20. The diameter of the holes in the high - thermal - conductivity porous part 23 is larger than the molecular length of the medium 27 and is sized not to impede the entry and exit of the medium 27. For example, the diameter of the holes in the high - thermal - conductivity porous part 23 is preferably 10 times or more, more preferably 50 times or more, and particularly preferably 100 times or more the mean free path of the vaporized medium (guest molecules). Thereby, the high - thermal - conductivity porous part 23 has the selectivity of allowing the medium 27 to permeate without passing through the nanoporous body 20.

[0033] The high thermal conductivity porous portion 23 is preferably made of, for example, a metal or an alloy. This makes it easy to have a higher thermal conductivity than the nanoporous body 20. Examples of such a metal or alloy include copper (Cu) or a Cu alloy, aluminum (Al) or an Al alloy.

[0034] Also, the high thermal conductivity porous portion 23 is preferably, for example, a mesh having a large number of through holes. Examples of the high thermal conductivity porous portion 23 that has a higher thermal conductivity than the nanoporous body 20, has holes larger than the pore diameter of the nanoporous body 20, and does not hinder the entry and exit of the medium 27 include a Cu mesh or a Cu alloy mesh, an Al mesh or an Al alloy mesh.

[0035] The high thermal conductivity porous portion 23 preferably has elasticity and is harder than the nanoporous body 20. This makes it easy for the stress applying portion 31 to apply stress to the nanoporous body 20 via the high thermal conductivity porous portion 23.

[0036] (a) Configuration Example 1 FIGS. 5 and 6 are a plan view and a cross-sectional view schematically showing Configuration Example 1 of the high thermal conductivity porous portion 23 according to an embodiment of the present invention. FIG. 6 shows a cross-section obtained by cutting the region where the holes h of the high thermal conductivity porous portion 23 shown in FIG. 5 are provided with a straight line along the X-axis direction. Further, in FIG. 6, the particles 201 constituting the nanoporous body 20 are also schematically shown together with the high thermal conductivity porous portion 23.

[0037] As shown in FIGS. 5 and 6, the high thermal conductivity porous portion 23 is provided with a plurality of holes h. When the cross-section obtained by cutting the high thermal conductivity porous portion 23 along a direction (for example, the X-Y plane parallel to the X-axis direction and the Y-axis direction) orthogonal to the thickness direction (for example, the Z-axis direction) is taken as a cross-section, the shape of the cross-section of the hole h is, for example, a perfect circle (that is, a round shape). Also, when the cross-section obtained by cutting the high thermal conductivity porous portion 23 along the thickness direction (for example, the Z-axis direction) is taken as a longitudinal section, the shape of the longitudinal section of the hole h is, for example, a quadrangle, and as an example, it is a rectangle long in the thickness direction (for example, the Z-axis direction).

[0038] The diameter D of each of the plurality of holes h (i.e., the diameter) is the same or substantially the same as each other (i.e., uniform), for example, 1 mm. Also, the arrangement interval (i.e., the pitch diameter) P of the plurality of holes h is uniform, for example, 1.1 mm. The porosity of the high thermal conductivity porous portion 23 is 64.9%.

[0039] Thus, the plurality of holes h have the same shape and the same size as each other, and are regularly arranged in the X-axis direction and the Y-axis direction. Thereby, the length of the space 231 between one adjacent hole h and the other hole h (i.e., between the holes) can be made uniform, and the moving distance of the medium 27 in the space 231 can be made uniform over the entire surface of the nanoporous body 20. Thereby, the bias of heat generation and heat absorption in the entire nanoporous body 20 can be reduced, and the output of heat generation and heat absorption can be improved over the entire nanoporous body 20.

[0040] (b) Configuration Example 2 FIG. 7 and FIG. 8 are a plan view and a cross-sectional view schematically showing Configuration Example 2 of the high thermal conductivity porous portion 23 according to an embodiment of the present invention. FIG. 8 shows a cross-section of the region where the holes h of the high thermal conductivity porous portion 23 shown in FIG. 7 are provided, cut along a straight line in the X-axis direction. Also, in FIG. 8, together with the high thermal conductivity porous portion 23, the particles 201 constituting the nanoporous body 20 are also schematically shown. In Configuration Example 2 shown in FIGS. 7 and 8, the difference from Configuration Example 1 shown in FIGS. 5 and 6 lies in the shape of the longitudinal section of the holes h of the high thermal conductivity porous portion 23. Other configurations are the same as those of Configuration Example 1 shown in FIGS. 5 and 6.

[0041] As shown in FIG. 7, the shape of the cross-section of each of the plurality of holes h is, for example, a perfect circle. Also, as shown in FIG. 8, the shape of the longitudinal section of each of the plurality of holes h is tapered. The diameter of the hole h is larger on the side closer to the nanoporous body 20 and gradually decreases as it moves away from the nanoporous body 20. Regarding the diameter of the hole h, if the diameter of the opening surface on the side adjacent to the nanoporous body 20 is D1 and the diameter of the opening surface on the opposite side is D2, then D1 > D2.

[0042] The diameter D1 of each of the plurality of holes h is the same as or substantially the same as each other. Also, the diameter D2 of each of the plurality of holes h is the same as or substantially the same as each other. The plurality of holes h are regularly arranged in the X-axis direction and the Y-axis direction. Thereby, also in Configuration Example 2, similarly to Configuration Example 1, the length of the space between holes 231 can be made uniform, and the movement distance of the medium 27 in the space between holes 231 can be made uniform over the entire surface of the nanoporous body 20. The bias of heat generation and heat absorption over the entire nanoporous body 20 can be reduced, and the output of heat generation and heat absorption over the entire nanoporous body 20 can be improved.

[0043] Also, when the plurality of holes h are regularly arranged in the X-axis direction and the Y-axis direction, the larger the diameter of the holes h, the smaller the space between holes 231, and the shorter the movement distance of the medium 27 in the space between holes 231. In Configuration Example 2, the shape of the longitudinal section of the hole h is tapered, and the diameter D1 of the opening surface on the side adjacent to the nanoporous body 20 is larger than the diameter D2 of the opening surface on the opposite side. Thereby, on the side adjacent to the nanoporous body 20, since the movement distance of the medium 27 in the space between holes 231 is shortened, it is possible to further improve the output of heat generation and heat absorption.

[0044] Also, when the plurality of holes h are regularly arranged in the X-axis direction and the Y-axis direction, the smaller the diameter of the holes h, the larger the space between holes 231. The larger the space between holes 231, the larger the contact area between the member constituting the high heat conduction porous portion 23 (for example, a metal such as Cu or a Cu alloy) and other members. Therefore, it is possible to further enhance the thermal conductivity between the high heat conduction porous portion 23 and other members.

[0045] In Configuration Example 2, since D1 > D2, the high thermal conductivity porous portion 23 has a larger contact area with other members located on the side opposite to the side adjacent to the nanoporous body 20 (for example, the outside of the nanoporous body pack 2). Thereby, the thermal conductivity between the high thermal conductivity porous portion 23 and other members can be enhanced. As other members, there are other nanoporous body packs 2 adjacent in the stacking direction (for example, the Z-axis direction) of the nanoporous body pack 2, the contact portion 291 (see FIGS. 1 and 2) which is a part of the heat conduction portion 29, the first pressing plate 131A and the second pressing plate 131B which are parts of the stress applying portion 31.

[0046] (c) Configuration Example 3 FIG. 9 is a plan view and a cross-sectional view schematically showing Configuration Example 3 of the high thermal conductivity porous portion 23 according to the embodiment of the present invention. In Configuration Example 3 shown in FIG. 9, the difference from Configuration Example 1 shown in FIGS. 5 and 6 lies in the shape of the cross section of the holes h of the high thermal conductivity porous portion 23. Other configurations are the same as those of Configuration Example 1 shown in FIGS. 5 and 6.

[0047] As shown in FIG. 9, the shape of the cross section of each of the plurality of holes h is, for example, a quadrilateral, and more specifically, a square. Although not shown, the shape of the longitudinal section of each of the plurality of holes h is, for example, a quadrilateral, and more specifically, a rectangle that is long in the thickness direction (for example, the Z-axis direction).

[0048] Also in Configuration Example 3, similar to Configuration Example 1, the diameter D of each of the plurality of holes h is the same or substantially the same as each other, for example, 1 mm. Also, the arrangement interval P of the plurality of holes h is uniform, for example, 1.1 mm. In Configuration Example 3, the aperture ratio of the high thermal conductivity porous portion 23 is 82.6%.

[0049] Also in Configuration Example 3, similar to Configuration Example 1, the plurality of holes h have the same shape and the same size as each other, and are regularly arranged in the X-axis direction and the Y-axis direction. Therefore, the movement distance of the medium 27 between the holes can be made uniform over the entire surface of the nanoporous body 20. The bias of heat generation and heat absorption in the entire nanoporous body 20 can be reduced, and the output of heat generation and heat absorption can be improved over the entire nanoporous body 20.

[0050] Further, in Configuration Example 3, compared with Configuration Example 1, it is easy to increase the porosity of the high thermal conductivity porous portion 23. The larger the porosity of the high thermal conductivity porous portion 23, the more uniformly the medium 27 can pass through the holes h. Also, the larger the porosity of the high thermal conductivity porous portion 23, the smaller the space between the holes becomes, and the moving distance of the medium 27 between the holes is shortened. As a result, the adsorption / desorption performance of the medium 27 is improved, and it becomes possible to further improve the output of heat generation / heat absorption.

[0051] Note that as a modification of Configuration Example 3, the shape of the longitudinal section of the hole h may be tapered as shown in FIG. 8. Thereby, similar to Configuration Example 2, it becomes possible to further improve the output of heat generation / heat absorption or to further enhance the thermal conductivity between the high thermal conductivity porous portion 23 and other members.

[0052] (d) Configuration Example 4 FIG. 10 is a plan view and a cross-sectional view schematically showing Configuration Example 4 of the high thermal conductivity porous portion 23 according to an embodiment of the present invention. In Configuration Example 4 shown in FIG. 10, the difference from Configuration Example 1 shown in FIGS. 5 and 6 lies in the shape of the cross section of the hole h of the high thermal conductivity porous portion 23. Other configurations are the same as those of Configuration Example 1 shown in FIGS. 5 and 6.

[0053] As shown in FIG. 10, the shape of the cross section of each of the plurality of holes h is, for example, hexagonal, and more specifically, regular hexagonal. Although not shown, the shape of the longitudinal section of each of the plurality of holes h is, for example, quadrilateral, and more specifically, a rectangle that is long in the thickness direction (for example, the Z-axis direction).

[0054] Also in Configuration Example 4, similar to Configuration Example 1, the diameter D of each of the plurality of holes h is the same or substantially the same as each other, for example, 1 mm. Also, the arrangement interval P of the plurality of holes h is uniform, for example, 1.1 mm. In Configuration Example 4, the porosity of the high thermal conductivity porous portion 23 is 82.6%.

[0055] Also in Configuration Example 4, similar to Configuration Example 1, the plurality of holes h have the same shape and the same size as each other, and are regularly arranged in the X-axis direction and the Y-axis direction. Therefore, the movement distance of the medium 27 between the holes can be made uniform over the entire surface of the nanoporous body 20. The bias in heat generation and heat absorption throughout the nanoporous body 20 can be reduced, and the output of heat generation and heat absorption can be improved throughout the nanoporous body 20.

[0056] Further, in Configuration Example 4, it is easier to increase the aperture ratio of the high thermal conductivity porous portion 23 compared to Configuration Example 1. The larger the aperture ratio of the high thermal conductivity porous portion 23, the more uniformly the medium 27 can pass through the holes h. Also, the larger the aperture ratio of the high thermal conductivity porous portion 23, the smaller the space between the holes, and the shorter the movement distance of the medium 27 between the holes. Thereby, the adsorption / desorption performance of the medium 27 is improved, and it becomes possible to further improve the output of heat generation and heat absorption.

[0057] Note that as a modification of Configuration Example 4, the shape of the longitudinal section of the hole h may be tapered as shown in FIG. 8. Thereby, similar to Configuration Example 2, it becomes possible to further improve the output of heat generation and heat absorption, or to further enhance the thermal conductivity between the high thermal conductivity porous portion 23 and other members.

[0058] (Thermal conduction part) As shown in FIGS. 1 and 2, the thermal conduction part 29 has a contact part 291 that is housed in the housing part 32 and is in direct or indirect contact with the nanoporous body 20 via the high thermal conductivity porous part 23, and an extension part 292 that is connected to the contact part 291 and extends from the housing part 32. The extension part 292 may be referred to as a fin part. The contact part 291 and the extension part 292 are integrally formed of a single metal plate. The contact part 291 exchanges heat with the nanoporous body 20 existing in the housing part 32, and the extension part 292 exchanges heat with an object (for example, air) existing outside the housing part 32.

[0059] (Stress application part) As shown in FIGS. 1 and 2, the stress applying portion 31 includes a first pressing plate 131A and a second pressing plate 131B arranged to face the first pressing plate 131A. The first pressing plate 131A and the second pressing plate 131B are arranged inside the accommodating portion 32. Between one surface of the first pressing plate 131A and the contact portion 291 (the upper surface in FIGS. 1 and 2), and A plurality of nanoporous body packs 2 are laminated and arranged between the second pressing plate 131B and the other surface of the contact portion 291 (the lower surface in FIGS. 1 and 2), respectively.

[0060] The first pressing plate 131A and the second pressing plate 131B move in a direction approaching each other Thereby, stress is applied to the nanoporous body pack 2 (that is, pressed). Further, the first pressing plate 131A and the second pressing plate 131B move in a direction away from each other to release the stress applied to the nanoporous body pack 2. As means for moving the first pressing plate 131A and the second pressing plate 131B, for example, a mechanical press using the rotational motion of a motor, a hydraulic press using fluid pressure such as hydraulic pressure, etc. can be used.

[0061] (Accommodating portion) The accommodating portion 32 is a container having a space inside that accommodates all of the plurality of nanoporous body packs 2, at least a part of the heat conducting portion 29 (for example, the contact portion 291), and a part of the stress applying portion 31 (for example, the first pressing plate 131A and the second pressing plate 131B), and further accommodates the medium 27. The inside of the accommodating portion 32 may be kept at a vacuum or a low pressure close to a vacuum, or may be kept at a normal pressure or a pressure close to a normal pressure. The accommodating portion 32 is preferably made of a material having excellent heat conductivity, and is preferably made of a metal or an alloy such as aluminum (Al) or an Al alloy, copper (Cu) or a Cu alloy. Thereby, the heat exchange device 100 can efficiently exchange heat with the object (for example, air) not only through the extending portion 292 of the heat conducting portion 29 but also through the accommodating portion 32.

[0062] (Medium) Examples of the medium include, for example, water or alcohol. Examples of alcohol include methanol or ethanol.

[0063] (Control unit) The heat exchanger 100 may further include a control unit (not shown). The control unit is composed of, for example, a CPU (Central Processing Unit), a RAM (Random Access Memory), and a recording medium. The CPU reads the program recorded on the recording medium into the RAM or the like and executes information processing and arithmetic processing. Thereby, the control unit can control the operation of the stress applying unit 31 to apply or release stress to the nanoporous body 20.

[0064] (Evaluation experiment of thermal conductivity) In order to evaluate the thermal conductivity of the nanoporous body pack 2 according to the embodiment, the inventor prepared an example and a comparative example and conducted an evaluation experiment.

[0065] (1) Example The configuration example 1 of the high thermal conductivity porous part 23 shown in FIGS. 5 and 6 was used as the example. The high thermal conductivity porous part according to the example is a Cu mesh, and the thermal conductivity is 386 [W / m·K]. The shape of the high thermal conductivity porous part (Cu mesh) according to the example is a bag shape that can contain the nanoporous body 20 as shown in FIGS. 3 and 4. GMS powder was arranged as the nanoporous body 20 inside the Cu mesh to form the nanoporous body pack 2 according to the example.

[0066] (2) Comparative example A filter cloth made of polypropylene (PP) was prepared as the porous part. The thermal conductivity of the PP filter cloth is 0.12 [W / m·K]. The shape of the PP filter cloth according to the comparative example is a bag shape that can contain the nanoporous body. The same amount of GMS powder as in the example was enclosed as the nanoporous body inside this bag to form the nanoporous body pack according to the comparative example.

[0067] (3) Experimental apparatus FIG. 11 is a perspective view schematically showing the configuration of the experimental apparatus 150 used in the evaluation experiment. As shown in FIG. 11, the experimental apparatus 150 includes a hot plate 151, a support member 155 disposed on the hot plate 151, a Cu plate 152, an acrylic plate 153, and a weight portion 154. The support member 155 has elasticity. The support member 155 is used to support five nano-porous body packs 2 stacked on the hot plate 151 from the side surface side.

[0068] As shown in FIG. 11, the Cu plate 152, the acrylic plate 153, and the weight portion 154 are disposed on the five nano-porous body packs 2 stacked on the hot plate 151.

[0069] (4) Experimental method As shown in FIG. 11, five nano-porous body packs 2 according to the examples were prepared, and the five nano-porous body packs 2 were stacked and arranged on the hot plate 151. Further, the support member 155 was disposed on the hot plate 151, and the support member 155 was brought into contact with each side surface of the five nano-porous body packs 2 to support the nano-porous body packs 2 so as not to collapse. In this state, the Cu plate 152, the acrylic plate 153, and the weight portion 154 were arranged on the nano-porous body pack 2 in this order. Then, the hot plate 151 was heated, and the temperature of the Cu plate 152 was measured.

[0070] The same measurement as above was also performed for the comparative example. That is, five nano-porous body packs according to the comparative example were prepared and stacked on the hot plate 151. With the side surfaces of the five nano-porous body packs supported by the support member 155, the Cu plate 152, the acrylic plate 153, and the weight portion 154 were arranged on the nano-porous body pack in this order. Then, the hot plate 151 was heated, and the temperature of the Cu plate 152 was measured.

[0071] (5) Results FIG. 12 shows the results of the thermal conductivity evaluation experiment conducted by the present inventors and is a graph showing the temperature changes of the examples and comparative examples. The horizontal axis in FIG. 12 indicates the elapsed time [seconds] since the start of temperature measurement of the Cu plate 152, and the vertical axis indicates the temperature change ΔT [° C.] of the Cu plate 152.

[0072] As shown in FIG. 12, it was confirmed that the rate of temperature change of the Cu plate 152 in the examples was greater than that in the comparative examples. In the graph shown in FIG. 12, when calculating the rate of temperature change until ΔT = 6 [° C.], the comparative example was 0.007 [K / s], whereas the example was 0.013 [K / s]. From this result, it was confirmed that the nanoporous body pack 2 according to the example using the Cu mesh has higher thermal conductivity than the nanoporous body pack according to the comparative example using the PP filter cloth.

[0073] (Effect of Embodiment) As described above, the heat exchanger 100 according to the embodiment of the present invention includes a nanoporous body 20 having elasticity, capable of contracting to desorb the medium 27, and capable of expanding to adsorb the medium 27; adjacent to the surface of the nanoporous body 20, not passing through the nanoporous body 20, having selectivity for permeating the medium 27, and a high thermal conductivity porous portion 23 made of a porous material having higher thermal conductivity than the nanoporous body 20; a heat conducting portion 29 that is in direct or indirect contact with the nanoporous body 20 and conducts the heat of the nanoporous body 20; a stress applying portion 31 that applies a stress to the nanoporous body 20 to contract the nanoporous body 20 and releases the applied stress to expand the nanoporous body 20; and a housing portion 32 that houses the nanoporous body 20, the high thermal conductivity porous portion 23, and the medium 27 inside.

[0074] According to the heat exchanger 100 according to the embodiment of the present invention, a nanoporous body 20 containing a nanoporous material that can change the pore diameter by applying and releasing stress and reversibly adsorb and desorb a medium taken in as a medium is used as an adsorbent. Thereby, heat exchange can be performed with a substance (for example, air) existing outside the housing portion 32 using the nanoporous body 20 that absorbs or generates heat due to the phase change of the medium 27 as a heat source. In the heat exchanger 100, instead of heat input by a heater, pressing by the stress applying portion 31 serves as input energy. Therefore, the heat exchanger 100 can improve the energy consumption efficiency (COP: Coefficient Of Performance). Further, since the heat exchanger 100 does not require a heater for heat input, it can be miniaturized.

[0075] Further, in the heat exchanger 100, a high heat conduction porous portion 23 is disposed adjacent to the surface of the nanoporous body 20. The high heat conduction porous portion 23 has a selectivity of allowing the medium 27 to pass through without passing through the nanoporous body 20 and is made of a porous material having higher heat conductivity than the nanoporous body 20. The high heat conduction porous portion 23 does not block the pores h even when stress is applied by the stress applying portion 31. By disposing the high heat conduction porous portion 23 adjacent to the surface of the nanoporous body 20, the heat of the nanoporous body 20 can be efficiently transmitted to the heat conduction portion 29, so that the energy consumption efficiency can be further improved.

[0076] Further, the nanoporous body 20 and the high heat conduction porous portion 23 including the nanoporous body 20 constitute a nanoporous body pack 2. Thereby, it is possible to prevent the nanoporous body 20 from collapsing or impurities from being mixed into the nanoporous body 20 when mechanical stress is applied to the nanoporous body 20. Since a decrease in the adsorption / desorption amount due to the collapse of the nanoporous body 20 is unlikely to occur, the heat absorption / generation amount can be maintained.

[0077] In addition, a highly thermally conductive porous portion 23 is interposed between the nanoporous body 20 and another member (for example, the inner wall of the stress applying portion 31 or the accommodating portion 32). As a result, compared with the case where the nanoporous body 20 and another member are in direct contact, air permeability can be ensured on the surface of the nanoporous body 20, and it becomes easier to transport the medium 27 to the nanoporous body 20, so that the heat exchange performance can be further enhanced.

[0078] (Modification example) FIGS. 13 and 14 are a plan view and a cross-sectional view schematically showing a modification example of the highly thermally conductive porous portion 23 according to an embodiment of the present invention. FIG. 14 shows a cross-section obtained by cutting a region where the holes h of the highly thermally conductive porous portion 23 shown in FIG. 13 are provided with a straight line along the X-axis direction. Further, in FIG. 14, together with the highly thermally conductive porous portion 23, the particles 201 constituting the nanoporous body 20 are also schematically shown. As shown in FIGS. 13 and 14, the shape and size of the holes h of the highly thermally conductive porous portion 23 may not be uniform and may be non-uniform. Also, the arrangement of the holes h of the highly thermally conductive porous portion 23 may not be regular and may be random.

[0079] Even with such a configuration, since the highly thermally conductive porous portion 23 is disposed adjacent to the surface of the nanoporous body 20, the heat of the nanoporous body 20 can be efficiently transmitted to the heat conducting portion 29. Thereby, it is possible to improve the energy consumption efficiency. Also, in this modification example too, it is possible to constitute the nanoporous body pack 2 by the nanoporous body 20 and the highly thermally conductive porous portion 23. Thereby, it is possible to suppress the collapse of the nanoporous body 20 or the mixing of impurities into the nanoporous body 20 when a mechanical stress is applied to the nanoporous body 20.

Explanation of reference numerals

[0080] 2 Nanoporous body pack 20 Nanoporous body 23 Highly thermally conductive porous portion 27 Medium 29 Heat conducting portion 31 Stress applying portion 32 Accommodating portion 100 Heat exchanger device, 131A First press plate 131B Second press plate 291 Contact part 292 Extension part h Hole

Claims

1. A nanoporous body having elasticity, capable of contracting to desorb a medium, and capable of expanding to adsorb a medium; A high thermal conductivity porous part adjacent to the surface of the nanoporous body, having selectivity to allow the medium to permeate without passing through the nanoporous body, and made of a porous material having higher thermal conductivity than the nanoporous body; A heat conducting part in direct or indirect contact with the nanoporous body to conduct the heat of the nanoporous body; A stress applying part that performs an operation of applying stress to the nanoporous body to contract the nanoporous body and an operation of releasing the applied stress to expand the nanoporous body; A heat exchange device comprising the nanoporous body, the high thermal conductivity porous part, and a housing part that houses the medium therein.

2. The high thermal conductivity porous part has a plurality of pores having the same or substantially the same diameter; The heat exchange device according to claim 1, wherein the plurality of pores are regularly arranged in a plane direction intersecting the thickness direction of the high thermal conductivity porous part.

3. When a cross section obtained by cutting the high thermal conductivity porous part along the thickness direction is defined as a longitudinal section, The heat exchange device according to claim 2, wherein the shape of the longitudinal section of the pore is tapered.

4. The heat exchange device according to claim 3, wherein the diameter of the pore is larger on the side closer to the nanoporous body and smaller on the side farther from the nanoporous body.

5. When a cross section obtained by cutting the high thermal conductivity porous part along a direction intersecting the thickness direction is defined as a transverse section, The heat exchange device according to any one of claims 2 to 4, wherein the shape of the transverse section of the pore is a quadrilateral.

6. When a cross section obtained by cutting the high thermal conductivity porous part along a direction intersecting the thickness direction is defined as a transverse section, The heat exchange device according to any one of claims 2 to 4, wherein the shape of the pore in the transverse section is a hexagon.

7. The heat exchange device according to claim 1, wherein the plurality of pores of the high thermal conductivity porous part are randomly arranged in a plane direction intersecting the thickness direction of the high thermal conductivity porous part.

8. The heat exchange device according to any one of claims 1 to 4, wherein the high thermal conductivity porous part is made of a metal or an alloy.

9. The heat exchange device according to any one of claims 1 to 4, wherein the nanoporous body and the high thermal conductivity porous part including the nanoporous body constitute a nanoporous body pack.

10. Comprising a plurality of the nanoporous body packs The heat exchange device according to claim 9, wherein the plurality of nanoporous packs are laminated in a direction in which the stress is applied by the stress applying portion.

11. Comprising a plurality of the nanoporous packs, The heat conducting portion has a contact portion that is thermally connected in contact with the nanoporous pack inside the accommodating portion, and an extending portion that extends outward from the accommodating portion. The heat exchange device according to claim 9, wherein the plurality of nanoporous packs are laminated and arranged between the stress applying portion and the contact portion.

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