JP2019138620A - Heat exchange device - Google Patents

Abstract

To provide an adsorption type heat exchange device capable of reducing a device size by improving a coefficient of performance COP.SOLUTION: A heat exchange device 10 includes heat exchange units 30A and 30B provided with a nano porous body 20 having elasticity which is contracted and can desorb a medium 60, and is expanded and can adsorb the medium, stress application parts 31A and 31B for applying stress to the nano porous body and contracting it, and chambers 32A and 32B for housing the nano porous body inside. The heat exchange device further includes a control unit 40 for controlling operation of the stress application parts and switching an operation mode in the heat exchange units between a desorption mode for applying stress to the nano porous body to contract it, and desorb the medium from the nano porous body, and an adsorption mode for releasing the stress to expand the nano porous body, and causing the nano porous body to adsorb the medium.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an adsorption heat exchange device.

  Conventionally, a heat exchange device that heats or cools an object (space or object) by moving heat has been widely used. For example, the following Patent Document 1 discloses an adsorption heat exchange including an evaporator that vaporizes a medium, an adsorber that includes an adsorbent that desorbs and adsorbs the vaporized medium, and a condenser that condenses the vaporized medium. An apparatus is disclosed.

Japanese Patent Laying-Open No. 2015-183930

  The conventional adsorptive heat exchange apparatus disclosed in Patent Document 1 uses the latent heat of the medium in the evaporator and the condenser as cold and hot heat. Large energy is required for heating and cooling. Energy is also required for heating to regenerate the adsorbent that has adsorbed the medium. As a result, the coefficient of performance COP decreases. For this reason, more media are required to obtain the desired cooling and heating. As the amount of the medium increases, the amount (volume) of the adsorbent also increases. Furthermore, since an evaporator and a condenser are required, the heat exchange device becomes large. For this reason, it has been difficult to apply the conventional adsorption heat exchanger to a use such as a car air conditioner in which installation space is limited.

  Therefore, an object of the present invention is to provide an adsorption heat exchange device that can improve the coefficient of performance COP and reduce the size of the device.

  The present inventors have intensively studied to solve the above problems. In the process, a nanoporous body was found that can be mechanically deformed by applying and releasing stress to desorb and adsorb the medium. Furthermore, it has been discovered that by desorbing and adsorbing the medium on the nanoporous material, it is possible to change the phase of the medium and generate latent heat. And it tried to use the said nanoporous body as an adsorbent of a heat exchange apparatus. As a result, the latent heat generated by desorption or adsorption can be directly used for cooling or warming, and it has been found that the above problems can be solved, and the present invention has been completed.

  The heat exchanging device according to the present invention has elasticity, is capable of shrinking and desorbing the medium, and is capable of expanding and adsorbing the medium, and is contracted by applying stress to the nanoporous body. And a heat exchanging portion including a chamber for accommodating the nanoporous material therein. The heat exchange device further includes a control unit that controls the operation of the stress applying unit and switches the operation mode in the heat exchange unit between the desorption mode and the adsorption mode. Here, the desorption mode is an operation mode in which stress is applied to the nanoporous body to cause the medium to shrink and the medium is desorbed from the nanoporous body. The desorption mode is an operation mode in which stress is released and the nanoporous body is expanded to adsorb the medium to the nanoporous body.

  According to the heat exchange device of the present invention, by applying stress to the nanoporous material and releasing and contracting and expanding, the nanoporous material is desorbed and adsorbed to generate latent heat due to phase change. Can do. As a result, the latent heat generated by the desorption and adsorption of the medium can be directly used for cold or warm heat, so that an evaporator and a condenser are not necessary. In addition, since it is not necessary to reduce the pressure or heat in the evaporator or condenser in order to obtain latent heat, the energy required for the thermal cycle can be reduced. Thereby, since the coefficient of performance COP can be improved, the amount of the nanoporous material to be used can be reduced. Thus, an evaporator and a condenser become unnecessary, and since the quantity of a nanoporous body can be reduced, a heat exchange apparatus can be reduced in size.

It is a schematic sectional drawing which shows the structure of the heat exchange apparatus which concerns on 1st Embodiment. It is a figure for demonstrating the principle of the adsorption | suction effect | action of a solid surface. It is a figure for demonstrating the principle of the adsorption effect of the nanoporous body which concerns on this embodiment. It is a state figure of a refrigerant. It is a figure which shows a mode that a nanoporous body is contracted and a refrigerant | coolant is desorbed. It is a figure which shows a mode that a nanoporous body is freely expanded and a refrigerant | coolant is adsorbed. The TS diagram of the heat cycle of the heat exchange apparatus concerning a 1st embodiment is shown. It is a schematic sectional drawing for demonstrating operation | movement of the heat exchange apparatus which concerns on 1st Embodiment. It is a schematic sectional drawing for demonstrating operation | movement of the heat exchange apparatus which concerns on 1st Embodiment. It is a schematic sectional drawing for demonstrating operation | movement of the heat exchange apparatus which concerns on 1st Embodiment. It is a schematic sectional drawing for demonstrating operation | movement of the heat exchange apparatus which concerns on 1st Embodiment. It is a schematic sectional drawing for demonstrating operation | movement of the heat exchange apparatus which concerns on 1st Embodiment. It is a schematic sectional drawing for demonstrating operation | movement of the heat exchange apparatus which concerns on 1st Embodiment. It is a schematic sectional drawing for demonstrating operation | movement of the heat exchange apparatus which concerns on 1st Embodiment. It is a schematic sectional drawing for demonstrating operation | movement of the heat exchange apparatus which concerns on 1st Embodiment. It is the schematic which shows the structure of the heat exchange apparatus which concerns on comparison. It is a figure showing the stress-volume strain curve of the sample prepared in Example 1 and a comparative example. It is a photograph which shows a mode that stress was applied and released to the sample prepared in Example 1 and the comparative example. It is the schematic which shows the press chamber apparatus for confirming the desorption / adsorption | suction of the water of a nanoporous body by application / release of stress. It is a figure showing the desorption / adsorption isotherm of the water at the time of the stress application of the sample prepared in Example 1 and the comparative example, and no stress application. It is a figure which shows the result of having measured the change of the water vapor pressure when applying / releasing stress to the sample of Example 1 repeatedly. 2 is a diagram illustrating a water adsorption isotherm of a sample of Example 1. FIG. It is a figure showing the stress-strain curve of a nanoporous body. It is the figure which showed the relationship between the coefficient of performance COP and the Young's modulus E of the heat exchange apparatus which concerns on embodiment of this invention. It is a figure showing the desorption / adsorption isotherm of ethanol of the sample prepared in Example 2 when stress is applied and when no stress is applied. 16 shows the ethanol desorption / adsorption isotherm when stress is applied to the sample during the desorption measurement when measuring the ethanol desorption / adsorption amount of the sample prepared in Example 2 shown in FIG. FIG. It is a schematic sectional drawing which shows the structure of the heat exchange apparatus which concerns on 2nd Embodiment. It is a schematic sectional drawing for demonstrating operation | movement of the heat exchange apparatus which concerns on 2nd Embodiment. It is a schematic sectional drawing for demonstrating operation | movement of the heat exchange apparatus which concerns on 2nd Embodiment. It is a schematic sectional drawing for demonstrating operation | movement of the heat exchange apparatus which concerns on 2nd Embodiment. It is a schematic sectional drawing for demonstrating operation | movement of the heat exchange apparatus which concerns on 2nd Embodiment. It is a figure showing the stress-strain curve of a nanoporous body. It is a schematic sectional drawing which shows the structure of the heat exchange apparatus which concerns on the modification of 2nd Embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the technical scope of the present invention should be determined based on the description of the scope of claims, and is not limited to the following embodiments. In addition, the dimension ratio of drawing is exaggerated on account of description, and may differ from an actual ratio.

[First Embodiment]
<Heat exchange device>
The heat exchange apparatus 10 according to the first embodiment of the present invention mechanically deforms the nanoporous body 20 by applying and releasing stress to desorb and adsorb the refrigerant (medium) 60. The object is cooled by using cold heat obtained from the latent heat of evaporation generated when the refrigerant 60 is desorbed. The heat exchange device 10 can be applied to, for example, a car air conditioner (cooling) that cools the interior (inside air) of an automobile.

  As shown in FIG. 1, the heat exchange device 10 includes a pair of heat exchange units 30A and 30B (first heat exchange unit 30A and second heat exchange unit 30B), and a control unit 40 that controls the operation of the entire device. . The control unit 40 performs a swing operation so that one of the pair of heat exchange units 30A and 30B is in the desorption mode, and the other operation mode is in the adsorption mode. Accordingly, it is possible to continuously generate cold heat in the heat exchange units 30A and 30B in the desorption mode. Here, the “desorption mode” is an operation mode in which the refrigerant 60 is desorbed from the nanoporous body 20. The “adsorption mode” is an operation mode in which the refrigerant 60 is adsorbed on the nanoporous body 20.

  The heat exchange device 10 includes a pipe 50 that allows the refrigerant 60 to move between the first chamber 32A and the second chamber 32B, and a valve 51 that switches between a communication state and a cutoff state of the pipe 50. When the valve 51 is opened, the pipe 50 is in a communication state, and when the valve 51 is closed, the pipe 50 is in a cutoff state.

[Heat exchange units 30A, 30B]
As shown in FIG. 1, the first heat exchange unit 30A includes a first nanoporous body 20A, a first stress applying unit 31A, a first chamber 32A, and a first air conditioning unit 33A. Similarly, the second heat exchange unit 30B includes a second nanoporous body 20B, a second stress applying unit 31B, a second chamber 32B, and an air conditioning unit 33B.

  The first heat exchange unit 30A and the second heat exchange unit 30B have the same configuration. In the following description, the first heat exchange unit 30A and the second heat exchange unit 30B are collectively referred to as “heat exchange units 30A and 30B”. Similarly, the first stress applying portion 31A and the second stress applying portion 31B are collectively referred to as “stress applying portions 31A and 31B”. The first chamber 32A and the second chamber 32B are collectively referred to as “chambers 32A and 32B”. The first air adjustment unit 33A and the second air adjustment unit 33B are collectively referred to as “air adjustment units 33A and 33B”. In addition, the first nanoporous body 20A and the second nanoporous body 20B are collectively referred to as “nanoporous body 20”.

[Nanoporous body 20]
The nanoporous body 20 is made of a nanoporous material that has elasticity, can be contracted by being able to desorb the refrigerant 60, and can be expanded to adsorb the refrigerant 60. The nanoporous body 20 is contracted by applying stress from the stress applying portions 31 </ b> A and 31 </ b> B and desorbs the refrigerant 60. When the stress is released, the nanoporous body 20 is freely expanded and adsorbs the refrigerant 60.

  Here, “elasticity” is a property in which even if stress is applied from the outside by the stress applying portions 31A and 31B and contracted, the stress is released to reversibly deform and revert to a substantially original shape. Means. The elastic limit of the nanoporous body 20 is designed to be larger than the stress application necessary to desorb the refrigerant 60. The elastic limit of the nanoporous body 20 is preferably designed as appropriate according to the cooling scale to which the heat exchange device 10 is applied.

  “Nanoporous” means having a plurality of nano-level pores. The nano-level pores are preferably 0.5 to 100 nm in diameter, more preferably 0.7 to 50 nm in diameter, and still more preferably micropores or mesopores in diameter 0.7 to 6 nm. In IUPAC (International Pure and Applied Chemistry Union), pores having a diameter of 2 nm or less are micropores, pores having a diameter of 2 to 50 nm are mesopores, and pores having a diameter of 50 nm or more are macropores ( macropore).

  From the viewpoint of reducing the work of the stress applying portions 31A and 31B necessary for shrinking the nanoporous body 20, it is preferable to design the Young's modulus of the nanoporous body 20 to 1.1 GPa or less. The reason for designing the Young's modulus to 1.1 GPa or less will be described later.

  As shown in FIG. 2A, generally, the solid surface has high potential energy due to van der Waals force, and has an action of condensing the molecules of the refrigerant 60. In particular, in the nanoporous body 20 according to the present embodiment, as shown in FIG. 2B, the refrigerant 60 adsorbed on the nanoporous body 20 is surrounded by small nano-level pore walls, so that the solid surface The potential energy due to van der Waals force (physical adsorption force) is extremely high. At this time, the gaseous refrigerant 60 is adsorbed on the pore walls of the nanoporous body 20 at a liquid density. That is, the adsorption to the nanoporous body 20 is a phenomenon of the same quality as the phase change from gas to liquid, and the heat of adsorption is almost equal to the latent heat of condensation.

  In the following description, it is assumed that the refrigerant 60 changes phase from gas to liquid when adsorbed on the nanoporous body 20, and changes from liquid to gas when desorbed. Further, it is assumed that the heat of adsorption is equal to the latent heat of condensation. In addition, the phase change by desorption | suction and adsorption | suction of the refrigerant | coolant 60 to the nanoporous body 20 was confirmed in the Example mentioned later.

  FIG. 3 shows a state diagram of the refrigerant 60. As indicated by a dotted line in FIG. 3, the refrigerant 60 having a liquid density inside the pores adsorbed on the pore walls of the nanoporous body 20 is in equilibrium with vapor having 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.

FIG. 4A is a diagram illustrating a state in which the nanoporous body 20 is contracted and the refrigerant 60 is desorbed. As shown in FIG. 4A, when stress is applied to the nanoporous body 20 (work W _ns [J]), the pores contract and the refrigerant 60 adsorbed on the pore walls is desorbed. At this time, the refrigerant 60 adsorbed at the density of the liquid is released again as a gas to the outside of the nanoporous body 20. The heat exchange device 10 can cool the target by using the latent heat of vaporization Q _L [J] at the time of desorption as cold heat.

FIG. 4B is a diagram illustrating a state in which the contracted nanoporous body 20 is freely expanded to adsorb the refrigerant 60. As shown in FIG. 4B, when the nanoporous body 20 releases the stress, the nanoporous body 20 freely expands, the pores return to the original size, and the refrigerant 60 can be adsorbed again. As described above, the refrigerant 60 is adsorbed on the pore walls of the nanoporous body 20 at a liquid density. That is, when the refrigerant 60 is adsorbed to the nanoporous body 20, the refrigerant 60 changes phase from gas to liquid and generates condensation latent heat Q _H [J].

  The material constituting the nanoporous body 20 is not particularly limited as long as it is elastic, contracts to be able to desorb the refrigerant 60, and expands to adsorb the refrigerant 60. Examples of such materials include zeolite template carbon (ZTC), graphene meso sponge (GMS), and the like. Zeolite template carbon (hereinafter referred to as “ZTC”) and graphene meso sponge (hereinafter referred to as “GMS”) are both composed of a single-layer graphene skeleton, and are necessary for the desorption and adsorption of the refrigerant 60. And has elastic properties.

ZTC is composed of a single-layer graphene sheet. Further, uniform pores (diameter of about 1.2 nm) are three-dimensionally regularly arranged and connected to each other, and have extremely high BET specific surface area and pore volume (maximum BET specific surface area of 4100 m ² / g, and the pore volume is known to be 1.8 cc / g). The ordered structure of ZTC was analyzed using an X-ray diffractometer (Rigaku, MiniFlex 600, CuK). Moreover, the BET specific surface area of ZTC was analyzed using liquid nitrogen adsorption (77K) (Microtrac BEL, BELSORB-max).

  The production method of ZTC is described in Nishihara, H. et al., Chemistry-European Journal 15, 5355 (2009) and the like. Specifically, first, a porous material (for example, zeolite or the like) having a structure in which pores are formed inside the structure and the pores are connected in a mesh shape is prepared as a template. Then, an organic compound (for example, acetylene, ethylene, etc.) is introduced into the surface of the porous material and inside the pores under heating conditions, and the organic compound is carbonized by heating to deposit carbon on the porous material. Let Here, the carbonization / carbon deposition of the organic compound can be performed by, for example, a chemical vapor deposition (CVD) method. And the porous material which is a casting_mold | template is removed. By this method, a carbon material (that is, ZTC) reflecting the three-dimensional structure of the template can be easily manufactured. ZTC manufactured by the above method is excellent in flexibility and elasticity, and can be elastically deformed reversibly until the pore diameter is about 1.2 nm to about 0.7 nm.

GMS is also a sponge-like mesoporous material having a large part of the pore wall composed of single-layer graphene and having fine pores of about 6 nm, and, like ZTC, has an extremely high BET specific surface area comparable to activated carbon. (About 2000 m ² / g). On the other hand, unlike activated carbon and carbon black, it contains almost no end of graphene that causes corrosion, and therefore has excellent corrosion resistance (oxidation resistance). In addition, due to the property of graphene that is flexible and tough, GMS is excellent in flexibility and elasticity, and can be elastically deformed reversibly until the diameter of the pore is about 5.8 nm to about 0.7 nm. it can.

  The production method of GMS is described in Nishihara, H. et al., Advanced Functional Materials, Vol. 26, 2016, 6418-6427. Specifically, first, metal oxide nanoparticles made of alumina or the like (for example, γ-alumina) are prepared as a nano-sized spherical base material. This material has a high catalytic activity for carbon coating by the CVD method described later and an excellent sintering resistance.

  Subsequently, the surface of the spherical base material (metal oxide nanoparticles) prepared above is coated with carbon by a CVD method using an organic compound as a carbon source. According to the carbon coating using this CVD method, it is possible to form a uniform carbon layer on the entire surface of the spherical base material (metal oxide nanoparticles). In addition, examples of the organic compound used in this case include methane, acetylene, ethylene, propylene, benzene, etc. Among them, from the viewpoint that coating with a large amount of carbon crystal can be achieved, methane is used as a carbon source. It is preferable to use it. In the CVD process, the organic compound may be introduced in a state where a spacer such as quartz sand (silica sand) is mixed with the spherical base material (metal oxide nanoparticles) for the purpose of improving the gas flow. Further, an inert gas such as nitrogen may be used as the carrier gas for introducing the organic compound, and the concentration of the carbon source in the mixed gas of the carrier gas and the carbon source (organic compound) is about 10 to 30% by volume. It is preferable.

  As the CVD process proceeds, the color of the sample changes to black, while the reaction vessel (eg, quartz tube) containing the sample is kept transparent, so carbon deposition is performed on a spherical substrate (metal oxide nanoparticles). This can be confirmed only on the surface. Here, since the spherical base material (metal oxide nanoparticles) is not sintered even after the CVD process, the shape of the carbon-coated spherical base material hardly changes from before the carbon coating. In this way, the (average) number of carbon layers coated on the surface of the spherical substrate (metal oxide nanoparticles) is not only the amount of carbon source (organic compound) input in the CVD process, but also during the CVD. It can be controlled based on the processing temperature, processing time, etc., and corresponds to the (average) number of graphene layers in the finally obtained GMS. The value of the (average) number of layers is not particularly limited, but is preferably 0.90 to 3.0, more preferably 0.95 from the viewpoint of exhibiting excellent desorption / adsorption characteristics with respect to the refrigerant 60. It is -2.0, More preferably, it is 0.98-1.5, Most preferably, it is 1.0-1.1. In addition, although there is no restriction | limiting in particular also about the processing temperature and processing time in a CVD process, Processing temperature becomes like this. Preferably it is 800-1000 degreeC, More preferably, it is 850-950 degreeC. The treatment time is preferably 1 to 10 hours, more preferably 2 to 6 hours.

  Thereafter, the spherical base material (metal oxide nanoparticles) used as a template is removed by chemical etching, leaving only the carbon layer coated on the surface of the spherical base material. At this time, an aqueous solution of strong acid or strong base may be used for chemical etching. An example of the strong acid is hydrofluoric acid (HF) (in this case, etching at room temperature is possible). Moreover, as a strong base, sodium hydroxide (NaOH) is mentioned, for example (In this case, it is preferable to heat to about 200-300 degreeC). When the spherical substrate (metal oxide nanoparticles) is removed by chemical etching, a carbon meso sponge (CMS; Carbon MesoSponge) having spherical mesopores is obtained as a precursor of GMS.

  Finally, the carbon meso sponge (CMS) thus obtained is washed with water as necessary, and then under reduced pressure at a temperature of about 1500 to 2000 ° C. (preferably 1700 to 1900 ° C.) for 30 minutes to Heat treatment is performed for about 2 hours. Thereby, crystallization of the carbon layer into graphene proceeds, and GMS is obtained. Here, since the spherical mesopores possessed by the carbon meso sponge (CMS) are very stable even at high temperatures during the heat treatment described above, the carbon meso sponge (CMS) is also obtained in the GMS thus obtained. ) Is retained. Since GMS has such mesopores, it can be elastically deformed flexibly like a sponge. Therefore, the refrigerant 60 can be desorbed by being contracted, and the refrigerant 60 can be adsorbed by being expanded, and can be suitably used as the nanoporous body 20 in the heat exchange device 10 according to the present embodiment.

[Stressing portions 31A and 31B]
The stress applying portions 31A and 31B apply stress to the nanoporous body 20 to contract as shown in FIG. 4A, and release the applied stress to freely expand the nanoporous body 20 as shown in FIG. 4B. . Thereby, the stress imparting portions 31A and 31B can control the pore diameter of the nanoporous body 20 with external stress.

  The configuration of the stress applying portions 31 </ b> A and 31 </ b> B is not particularly limited as long as the stress applying portions 31 </ b> A and 31 </ b> B can reciprocate in the direction approaching and separating from the nanoporous body 20 to apply and release stress to the nanoporous body 20. As the stress applying portions 31A and 31B, for example, a mechanical press machine using a rotational motion of a motor, a hydraulic press machine using a fluid pressure such as hydraulic pressure, or the like can be used.

[Chamber 32A, 32B]
The chambers 32A and 32B are containers having a space for accommodating the nanoporous body 20 therein. The insides of the chambers 32A and 32B are kept at a vacuum or a low pressure close to a vacuum. For this reason, the refrigerant 60 can change phase from liquid to gas at a relatively low temperature (see FIG. 3).

[Air conditioning units 33A and 33B]
The air adjusting units 33A and 33B switch between a cooling state in which the inside of the chambers 32A and 32B is thermally conducted with low-temperature air and an exhaust heat state in which heat is conducted with high-temperature air. Since the heat exchange device 10 of the present embodiment is a device for cooling an object, low-temperature air corresponds to the atmosphere of the object to be cooled. The air conditioning units 33A and 33B take out the cold heat necessary for cooling the target in the cooling state from the heat exchange units 30A and 30B. Further, the air conditioning units 33A and 33B are exhausted to exhaust heat generated from the heat exchange units 30A and 30B.

  When the heat exchange device 10 is applied to a car air conditioner (cooling) of an automobile, for example, low-temperature air can be used as vehicle interior air (inside air), and high-temperature air can be used as vehicle interior air (outside air). In the summer season when cooling is used, the outside air temperature is higher than the inside air temperature. For example, the outside air temperature is about 303K and the inside air temperature is about 298K. In the following description, low-temperature air is described as “inside air” in the vehicle interior, and high-temperature air is described as “outside air” outside the vehicle interior.

[Control unit 40]
The control unit 40 includes, for example, a CPU (Central Processing Unit) (not shown), a RAM (Random Access Memory), a computer-readable recording medium, and the like. A series of processes for realizing the control described later is recorded in a recording medium or the like in the form of a program, and the CPU reads the program into a RAM or the like and executes information processing / calculation processing. The control described later is realized.

  The control unit 40 controls the operations of the stress applying units 31A and 31B and the air adjusting units 33A and 33B. The control unit 40 switches the operation mode in the heat exchange units 30 </ b> A and 30 </ b> B between a desorption mode in which the refrigerant 60 is desorbed from the nanoporous body 20 and an adsorption mode in which the refrigerant 60 is adsorbed on the nanoporous body 20.

[Refrigerant 60]
In the present embodiment, water is used as the refrigerant 60. In general vapor compression heat exchange devices, fluorocarbon-based HFC-134a is widely used as a refrigerant. A general working pressure is 0.34 to 1.2 MPa and a temperature range is 277 to 323 K, and an operation at a high pressure is required, but an operation near room temperature is possible, and a coefficient of performance COP is 5 It is about ~ 7. On the other hand, since water has about 16 times the latent heat of vaporization compared to HFC-134a, the theoretically obtained cold heat is 16 times. Further, in the fluorocarbon refrigerants such as HFC-134a, the problem of ozone layer destruction has been improved, but the global warming potential is still large. On the other hand, natural refrigerants represented by water do not adversely affect the global environment.

  For the above reasons, the coefficient of performance COP can be improved by using water as the refrigerant 60, and the heat exchange device 10 that is friendly to the global environment can be provided.

  In addition, the refrigerant | coolant 60 applicable to this invention is not limited to water, For example, ethanol can also be used like Example 2 mentioned later.

<Thermal cycle of the heat exchange device 10>
Next, with reference to FIG. 5, the thermal cycle by the heat exchange apparatus 10 is demonstrated. FIG. 5 shows a TS diagram of the heat cycle of the heat exchange device 10. In the present invention, the refrigerant 60 is divided into the following four types. The first type is the amount that remains permanently adsorbed on the nanoporous body 20, and this is the refrigerant 61. The second type is a part that does not participate in cooling of the inside air among those that are desorbed and adsorbed by applying stress to the nanoporous body 20 and free expansion, and this is the refrigerant 62. The third type is a part related to cooling of the inside air among those desorbed and adsorbed by stress application to the nanoporous body 20 and free expansion, and this is used as the refrigerant 63. The fourth type is a portion that is permanently adsorbed as a gas phase without being adsorbed on the nanoporous body 20, and is referred to as a refrigerant 64. Note that only the refrigerant 63 is considered in FIG.

The heat cycle of the heat exchange device 10 is a reverse Carnot cycle. In the reverse Carnot cycle, the state of the refrigerant 63 is changed in the order of state 1 → state 2 → state 3 → state 4. The process from state 1 to state 2 in FIG. 5 is heated, the process from state 2 to state 3 is isothermal isotherm, the process from state 3 to state 4 is cooled, the process from state 4 to state 1 is isothermal and isothermal Each step of desorption is shown. Here, the refrigerant 63 is a saturated steam at a low temperature T _{1 in} the state 1, a superheated steam at a high temperature T _{2 in} the state 2, a liquid at a high temperature T _{3 in} the state 3, and a liquid at a low temperature T _{4 in} the state 4. It is. Here, temperatures _{T 1} and _{T 4} are equal _{T L,} temperature _{T 2} and _{T 3} are equally _{T H.}

In state 2 from state 1, the refrigerant 63 will superheated steam of hot T _H is heated from saturated vapor of low temperature T _L. At this time, the temperature of the refrigerant 63 rises without changing its phase as a gas. At the same time, the sensible heat _{Q sh1-2} [J] it is absorbed to increase the temperature of the refrigerant 61 and nanoporous body 20 from _{T L} to _{T H.} The refrigerant 63 is a gas, and its sensible heat is small compared to the sensible heat of the refrigerant 61, which is a liquid, and can be ignored. In the heat cycle of the heat exchange device 10, “sensible heat” includes not only the amount of heat necessary for the temperature change of the refrigerant 61 but also the amount of heat necessary for the temperature change of the nanoporous body 20.

In the state 2 to the state 3, the contracted nanoporous body 20 freely expands, and thereby the refrigerant 63 is adsorbed in the pores of the nanoporous body 20 (see FIG. 4B). Due to the adsorption, the refrigerant 63 changes phase from gas (water vapor) to liquid (water). Condensation latent heat Q _H [J] is exhausted with the phase change.

In state 4 from state 3, the refrigerant 63, becomes liquid cold T _L is cooled from a liquid of a high temperature T _H. At this time, the temperature of the refrigerants 61 and 63 decreases without changing the phase as it is in the liquid state. The temperature of the refrigerant 61, 63 and nanoporous body 20 in order to lower the _{T H} to _{T L,} the sensible heat _Q sh [J] is waste heat. In states 3 and 4, the refrigerant 63 is adsorbed in the pores. In addition, during the transition from the state 3 to the state 4, the gas refrigerant 62 is adsorbed to the nanoporous body 20 </ b> A as the temperature decreases, so the gas phase pressure of the system once decreases, but the nanoporous body 20 contracts. It is assumed that the vapor phase pressure of the system is returned to the original state 4 by desorbing the refrigerant 62 and reaching the state 4.

In the state 4 to the state 1, the nanoporous body 20 is contracted and the refrigerant 63 is desorbed (see FIG. 4A). Work from the outside necessary for contracting the nanoporous body 20 from state 3 to state 4 and from the outside necessary for contracting the nanoporous body 20 from state 4 to state 1 W _ns [J]. In addition, the refrigerant 63 undergoes a phase change from liquid (water) to gas (water vapor) by desorption. As the phase changes, the latent heat of vaporization Q _L [J] is absorbed. The heat exchange device 10 can cool the target by using the latent heat of vaporization Q _L [J] as cold heat.

<Control Method of Heat Exchanger 10>
Next, with reference to FIG. 6A-FIG. 6H, the control method of the heat exchange apparatus 10 of this embodiment is demonstrated. In the following description, states 1 to 4 mean states 1 to 4 shown in FIG. Further, the control unit 40 controls the operations of the stress applying units 31A and 31B and the air adjusting units 33A and 33B.

  As shown in FIGS. 6A to 6H, the heat exchange device 10 of the present embodiment is configured such that the heat exchange of the other heat exchange unit 30 </ b> A, 30 </ b> B is performed while the operation mode of one heat exchange unit is the desorption mode. Swing operation is performed so that the operation mode of the section becomes the adsorption mode.

  The “inside air” in FIGS. 6A to 6H indicates a state in which the insides of the chambers 32A and 32B are thermally conducted with the low-temperature air (vehicle interior air) to be cooled by the air adjusting units 33A and 33B. In addition, “outside air” in FIGS. 6A to 6H indicates a state in which the insides of the chambers 32A and 32B are thermally conducted with high-temperature air (vehicle compartment outside air) by the air adjusting units 33A and 33B. In addition, illustration of air control part 33A, 33B is abbreviate | omitted.

[First heat exchange unit 30A: desorption mode, second heat exchange unit 30B: adsorption mode]
6A to 6C show the heat exchange device 10 in a state where the first heat exchange unit 30A is in the desorption mode and the second heat exchange unit 30B is in the adsorption mode.

(Start of desorption mode / adsorption mode)
FIG. 6A shows a state at the start of the desorption mode of the first heat exchange unit 30A and the adsorption mode of the second heat exchange unit 30B. At this time, the refrigerant 63 in the first chamber 32A is in an intermediate stage between the state 3 and the state 4, and the refrigerant 63 in the second chamber 32B is in an intermediate stage between the state 1 and the state 2, respectively. The first nanoporous body 20A in the first chamber 32A is in a state of free expansion without application of stress from the first stress applying part 31A. The second nanoporous body 20B in the second chamber 32B is in a contracted state due to the application of stress from the second stress applying part 31B. The valve 51 is in a closed state.

Refrigerant 62 and 63 in the first chamber 32A is a state adsorbed on the first nano-porous body 20A is completed at a temperature _{T 4.} At this time, the gas phase pressure in the first chamber 32A is lower than the state 3 and the state 4. Refrigerant 62 and 63 in the second chamber 32B is a state of detachment from second nanoporous body 20B is completed at a temperature _{T 2.} At this time, the gas phase pressure in the second chamber 32B is higher than the state 2 and the state 3. Even in the first chamber 32A where the adsorption has been completed, the refrigerant 64 remains in a gaseous state without being adsorbed. Similarly, in the second chamber 32B where the desorption is completed, the refrigerant 61 is not desorbed and remains in a state of being permanently adsorbed inside the nanoporous body 20 in a liquid state. For the refrigerant 61 that remains permanently in the nanoporous body 20, only the sensible heat change is considered in the calculation of the coefficient of performance COP, which will be described later.

  In the first heat exchanging unit 30A, the inside of the first chamber 32A is in thermal conduction with the inside air that is the object of cooling. In the second heat exchange unit 30B, the inside of the second chamber 32B is in thermal conduction with the outside air.

Temperature _{T 4} in the first chamber 32A is lower than the temperature _{T 2} in the second chamber 32B. Further, the internal pressure of the first chamber 32A is lower than the internal pressure of the second chamber 32B. For this reason, the valve 51 is in a closed state.

  When the first heat exchange unit 30A starts the desorption mode, the first stress applying unit 31A applies compressive stress to the first nanoporous body 20A to contract the first nanoporous body 20A. As a result, the pores of the first nanoporous body 20A contract and the refrigerant 62 is desorbed.

In the heat exchange device 10, the first heat exchange unit 30 </ b> A and the second heat exchange unit 30 </ b> B are alternately in the desorption mode. The COP calculation is related to the fact that any one of the heat exchange units is in the desorption mode. This is the work W _ns [J] required to desorb 62 and 63.

The refrigerant 60 increases the pressure in the first chamber 32A by desorption and brings the system to the state 4. _Along with the phase change of the refrigerant 62, latent heat of vaporization Q _L3-4 [J] is generated. As will be described later, this latent heat of vaporization Q _L3-4 [J] is not used as cold because it is used to offset the amount of latent heat of condensation Q _H3-4 [J] of the refrigerant 62 shown in FIG. 6H.

On the other hand, when the second heat exchange unit 30B starts the adsorption mode, the second heat exchange unit 30B releases the stress applied to the first nanoporous body 20A from the second stress applying unit 31B. Thereby, the second nanoporous body 20B freely expands and the pores are restored to the original shape, and at the same time, the refrigerant 62 existing as vapor is adsorbed. Then, the pressure in the second chamber 32B decreases and the system reaches the state 2. Condensation latent heat Q _H1-2 [J] is generated along with the phase change. The condensation latent heat Q _H1-2 [J] is _exhausted to the outside air by the air adjusting unit 33B.

  During the above process, the internal pressure (vapor pressure) of the first chamber 32A increases while the internal pressure (vapor pressure) of the second chamber 32B decreases. At the start of the process, since the internal pressure of the first chamber 32A is lower than the internal pressure of the second chamber 32B, the internal pressure of the first chamber 32A approaches the internal pressure of the second chamber 32B.

(Open valve 51)
As shown in FIG. 6B, when the internal pressure of the first chamber 32A and the internal pressure of the second chamber 32B become equal, the valve 51 is opened. At this time, the refrigerant 63 in the first chamber 32A is in the state 4, and the refrigerant 63 in the second chamber 32B is in the state 2. After opening the valve 51, desorbed saturated vapor state 1 in the first chamber 32A is moved to the second chamber 32B through the pipe 50 changes to superheated steam temperature T _2. In this manner, the saturated vapor refrigerant 63 is continuously supplied from the first chamber 32A to the second chamber 32B. The enthalpy change (H ₃ −H ₂ ) from state 2 to state 3 corresponds to the amount of heat Q _H [J] exhausted from the second chamber 32B to the outside air.

In the first heat exchange unit 30 </ b> A, the latent heat of vaporization Q _L [J] is generated by the desorption of the refrigerant 63. The latent heat of vaporization Q _L [J] after opening the valve 51 is used as cold heat for cooling the inside air.

(End of desorption mode / adsorption mode; valve 51 is closed)
FIG. 6C shows a state where the second nanoporous body 20B has reached a limit where it can no longer freely expand. In this state, the adsorption mode of the second heat exchange unit 30B is terminated. Simultaneously with the end of the adsorption mode, the first heat exchange unit 30A stops applying stress to the first nanoporous body 20A and ends the desorption mode. When the desorption mode / adsorption mode ends, the valve 51 is closed.

At the stage where the desorption mode and the adsorption mode are finished, the refrigerant 63 in the first chamber 32A is in the state 1, and the refrigerant 63 in the second chamber 32B is in the state 3. Temperature _{T L} in the first chamber 32A remains lower than the temperature _{T H} in the second chamber 32B. Immediately after closing the valve 51, the internal pressure of the first chamber 32A and the internal pressure of the second chamber 32B are equal. At this time, a part of the refrigerant 62 in the first chamber 32A is adsorbed on the nanoporous body 20A. A part of the refrigerant 62 exists in the second chamber 32B as a gas phase.

[Switch operation mode]
FIG. 6D is a diagram illustrating a state in which the operation mode of the heat exchange unit 30A is switched. The first heat exchange unit 30A is switched to the adsorption mode, and the second heat exchange unit 30B is switched to the desorption mode.

In the first heat exchanging unit 30A, the first chamber 32A is switched from a state in which heat is conducted with the inside air to a state in which heat is conducted with the outside air. In the 2nd heat exchange part 30B, the inside of the 2nd chamber 32B is switched from the state thermally conducted with outside air to the state thermally conducted with inside air. Since the outside air than shy of hot, the temperature in the first chamber 32A is increased from _{T L} to _{T H,} the temperature in the second chamber 32B is reduced to _{T L} from _{T H.}

In the first heat exchange unit 30A, by the temperature in the first chamber 32A is increased from _{T L} to _{T H,} in order to increase the _{T H} the temperature of the refrigerant 61 and the first nano-porous body 20A from _{T L} Sensible heat Q _sh1-2 [J] is _absorbed . Since the sensible heat Q _sh1-2 [J] absorbs heat from the outside air, it can be ignored in the calculation of the coefficient of performance COP described later. Further, although the sensible heat is generated because the refrigerant 63 changes from the state 1 (low temperature gas) to the state 2 (high temperature gas), this also absorbs heat from the outside air and can be ignored.

Further, the physical adsorption amount of the nanoporous body 20 is smaller as the temperature becomes higher. Accordingly, the first heat exchange unit 30A, when heated from a state that was reached desorption equilibrium at the temperature T _L to the temperature T _H desorption of the refrigerant 62 progresses. Evaporation latent heat Q _L1-2 [J] is generated by the desorption of the refrigerant 62. Since the latent heat of vaporization Q _L1-2 [J] absorbs heat from the outside air, it can be ignored in the calculation of the coefficient of performance COP described later. Note that the pressure in the first chamber 32A is higher than the pressure in the state 1 and the state 2 with the desorption.

In the second heat exchange unit 30B, the temperature in the second chamber 32B is by drops to _{T L} from _{T H,} the refrigerant 61 and 63 changes from state 3 (hot liquids) to state 4 (cryogenic liquid). Therefore, in the second heat exchange unit 30B, the sensible heat _Q sh [J] is shy waste heat to reduce the temperature of the refrigerant 61, 63 and the second nano-porous material 20B from _{T 3} to _{T 4.} As a result, the sensible heat Q _sh [J] increases the temperature of the inside air that is the object of cooling, resulting in a loss of thermal energy. Therefore, in the calculation of the coefficient of performance COP, it is necessary to subtract the sensible heat Q _sh [J] from the latent heat of vaporization Q _L [J] obtained as cold heat.

Further, the physical adsorption amount of the nanoporous body 20 is larger as the temperature is lower. Therefore, in the second heat exchange unit 30B, when cooled from the state at the temperature T _H has reached the adsorption equilibrium temperature T _L adsorption of the refrigerant 62 progresses. Condensation latent heat Q _H3-4 [J] is generated by the adsorption of the refrigerant 62. This condensation latent heat Q _H3-4 [J] increases the temperature of the inside air that is the object of cooling. However, since it can cancel out with the latent heat of vaporization Q _L3-4 [J] shown in FIG. 6E described later, it can be ignored in the calculation of the coefficient of performance COP described later.

  The relationship between the amount of physical adsorption of the nanoporous body 20 and the temperature (see FIG. 13) will be described in detail in the examples described later.

  Since desorption occurs in the first heat exchange unit 30A and adsorption occurs in the second heat exchange unit 30B, the internal pressure of the first chamber 32A is lower than the internal pressure of the second chamber 32B. At this time, since the valve 51 is closed, the refrigerant 60 can be prevented from flowing back from the low temperature second chamber 32B to the high temperature first chamber 32A due to the difference in internal pressure between the chambers 32A and 32B. For the above reasons, it is preferable to keep the valve 51 closed when switching the operation mode of the heat exchange units 30A and 30B (see FIG. 6D).

[First heat exchange unit 30A: adsorption mode, second heat exchange unit 30B: desorption mode]
6E to 6G show a state in which the first heat exchange unit 30A is in the desorption mode and the second heat exchange unit 30B is in the adsorption mode. 6E to 6G are diagrams in which the operation mode of the first heat exchange unit 30A and the operation mode of the second heat exchange unit 30B in FIGS. 6A to 6C are switched. Since the operation of the desorption mode and the operation of the adsorption mode of the two heat exchange units 30A and 30B are the same, the description overlapping with the above description will be omitted with reference to the above description.

(Start of desorption mode / adsorption mode)
FIG. 6E is a diagram in which the operation modes of the heat exchange units 30A and 30B in FIG. 6A are switched. FIG. 6E shows a state at the start of the adsorption mode of the first heat exchange unit 30A and the desorption mode of the second heat exchange unit 30B. Temperature _{T H} in the first chamber 32A is higher than the temperature _{T L} in the second chamber 32B.

In the first heat exchange unit 30A in the adsorption mode, the nanoporous body 20 is freely expanded and the refrigerant 62 is adsorbed to the nanoporous body 20 in the same manner as the operation of the second heat exchange unit 30B in FIG. 6A described above. Condensation latent heat Q _H1-2 [J] is generated that is exhausted to the outside air by adsorption.

In the second heat exchange unit 30B in the desorption mode, the nanoporous body 20 is contracted by the second stress applying unit 31B to desorb the refrigerant 62 in the same manner as the operation of the first heat exchange unit 30A in FIG. 6A described above. Let The latent heat of vaporization Q _L3-4 [J] that _absorbs heat from the inside air is generated by the desorption.

  During the above process, the internal pressure (water vapor pressure) of the first chamber 32A decreases while the internal pressure (water vapor pressure) of the second chamber 32B increases. At the start of the process, since the internal pressure of the first chamber 32A is higher than the internal pressure of the second chamber 32B, the internal pressure of the first chamber 32A approaches the internal pressure of the second chamber 32B.

(Open valve 51)
FIG. 6F is a diagram in which the operation modes of the heat exchange units 30A and 30B in FIG. 6B are switched. As shown in FIG. 6F, when the internal pressure of the first chamber 32A becomes equal to the internal pressure of the second chamber 32B, the valve 51 is opened. At this time, the refrigerant 63 in the first chamber 32A is in the state 2, and the refrigerant 63 in the second chamber 32B is in the state 4.

From the time when the valve 51 is closed (see FIG. 6C) to the time when the valve 51 is opened (see FIG. 6F), the amount of the refrigerant 62 adsorbed and desorbed by the second heat exchange unit 30B is equal. This is because when the valve 51 is closed and when the valve 51 is opened, the internal pressure of the first chamber 32A is equal to the internal pressure of the second chamber 32B. Therefore, the latent heat of vaporization Q _L3-4 [J] that has _absorbed heat from the inside air due to the desorption of the second heat exchange unit 30B shown in FIG. It is equal to latent heat Q _H3-4 [J]. For this reason, the part which raised the temperature of _{internal air} by condensation latent heat _QH3-4 [J] can be canceled by evaporation latent heat _QL3-4 [J]. For this reason, the inside air is cooled by the latent heat of vaporization Q _L [J] after the valve 51 is opened.

The work for generating the latent heat of evaporation Q _L3-4 [J] that does not contribute to cooling is W ₁ [J], and the work for generating the latent heat of evaporation Q _L [J] that contributes to cooling is W ₂ [J]. Then, the work W _ns [J] can be expressed by the following formula.

Here, the work W ₁ [J] is not energy for cooling the target, but is energy necessary for offsetting the condensation latent heat Q _H3-4 [J]. For this reason, it is necessary to consider the calculation of the coefficient of performance COP. Accordingly, the work W _ns [J] is used in the calculation of the coefficient of performance COP described later.

  Similar to the operation of FIG. 6B described above, the saturated steam in the state 1 desorbed in the second chamber 32B moves to the first chamber 32A via the pipe 50 and changes to the superheated steam in the state 2. Thereby, the refrigerant 60 is continuously supplied from the second chamber 32B to the first chamber 32A.

(End of desorption mode / adsorption mode; valve 51 is closed)
FIG. 6G is a diagram in which the operation modes of the heat exchange units 30A and 30B in FIG. 6C are switched. When the adsorption mode of the first heat exchange unit 30A and the desorption mode of the second heat exchange unit 30B are finished, the valve 51 is closed. At this time, the temperature _{T H} in the first chamber 32A remains in a state higher than the temperature _{T L} in the second chamber 32B.

[Switch operation mode]
FIG. 6H is a diagram illustrating a state in which the operation mode of the heat exchange unit 30A is switched. The first heat exchange unit 30A is switched to the desorption mode, and the second heat exchange unit 30B is switched to the adsorption mode.

In the first heat exchanging unit 30A, the inside of the first chamber 32A is switched from a state thermally conducted with the outside air to a state thermally conducted with the inside air. In the second heat exchanging unit 30B, the second chamber 32B is switched from a state in which heat is conducted with the inside air to a state in which heat is conducted with the outside air. Accordingly, the temperature of the first heat exchange unit 30A is changed from _{T 3} to _{T 4,} the temperature of the second heat exchange unit 30B is changed from _{T 1} to _{T 2.} The state shown in FIG. 6A is obtained by switching the operation mode.

As described above, in the control of the heat exchange device 10, the operation modes of the pair of heat exchange units 30A and 30B are alternately swung by repeating the operations shown in FIGS. 6A to 6H. Accordingly, it is possible to continuously generate cold heat due to the latent heat of vaporization Q _L [J] in the heat exchange units 30A and 30B in the desorption mode.

  FIG. 7 shows a configuration of a general adsorption heat exchange apparatus according to the proportionality. Note that states 1 to 4 in FIG. 7 correspond to states 1 to 4 in FIG. 5.

As shown in FIG. 7, the heat exchange device according to the proportional structure includes an evaporator that heats and vaporizes the refrigerant under reduced pressure, an adsorber that includes an adsorbent that desorbs and adsorbs the vaporized refrigerant, and the vaporized refrigerant. Has a condenser to condense. In the proportional heat exchange device, the latent heat of vaporization Q _L [J] in the evaporator is used for cooling. At the time of desorption / adsorption of the refrigerant to the adsorbent, the refrigerant does not change phase and remains a gas (water vapor), so no latent heat is generated. Desorption / adsorption is used to transport refrigerant. In the heat exchange device according to the comparative example, since the latent heat of evaporation in the evaporator is used for cooling, large energy is required for decompression and heating in the evaporator. Energy is also required for heating to regenerate the adsorbent that has adsorbed the medium. As a result, the coefficient of performance COP decreases.

On the other hand, the heat exchange device 10 according to the present embodiment changes the phase of the refrigerant 63 by applying stress to the nanoporous body 20 and uses the latent heat of vaporization (desorption heat) Q _L [J] as cold heat. Use. In addition, when the refrigerant 63 is desorbed from the nanoporous body 20, heating for regenerating the adsorbent, depressurization or heating with an evaporator is not required, and thus energy required for desorption can be reduced. it can. Thereby, since the coefficient of performance COP can be improved, the quantity of the nanoporous body 20 to be used can be reduced. Since an evaporator and a condenser become unnecessary and the quantity of the nanoporous body 20 can be reduced, the heat exchange apparatus 10 can be reduced in size.

<Calculation method of coefficient of performance COP>
Next, a method for calculating the coefficient of performance COP of the heat exchange device 10 according to the present embodiment will be described.

The heat exchange device 10 according to the present embodiment uses the evaporative latent heat Q _L [J] as cold heat by desorbing the refrigerant 63 from the nanoporous body 20 by work W _ns [J] from the outside. . As described above, in the state 3 to the state 4 of the heat cycle shown in FIG. 5, a loss of heat energy due to the sensible heat Q _sh [J] occurs. Therefore, in the calculation of the coefficient of performance COP, it is necessary to subtract the sensible heat Q _sh [J] from the latent heat of vaporization Q _L [J]. In addition, since the nanoporous body 20 is not a perfect elastic body, it is necessary to subtract the loss due to the internal friction Q _f [J] of the nanoporous body 20. For this reason, the coefficient of performance COP of the heat exchange device 10 is given by the following equation.

The process of state 3 → 4 is an isobaric change as a whole. Therefore, the sensible heat Q _sh is expressed by the following equation using the specific heat c _re [Jkg ⁻¹ K ⁻¹ ] of the liquid state refrigerant 60 and the specific heat c _ns [Jkg ⁻¹ K ⁻¹ ] of the nanoporous body 20. Can be represented.

_Here, w ns [kg] is the weight of the nano-porous material _{20, w re-ads [kg} ] is the amount of the refrigerant 60 that is adsorbed on the nanoporous material 20 at the temperature _{T H.} This is the sum of the refrigerant 61 and the refrigerant 63. Further, the temperature _{T H,} the chamber 32A of the suction mode, corresponds to a temperature within 32B, the temperature _{T L} is a chamber 32A of the desorption mode, corresponding to a temperature within 32B. In the adsorption mode chambers 32A and 32B, the amount of the vapor of the refrigerant 60 is small, and the influence of the sensible heat is extremely small compared to _Qsh, and can be ignored.

In the state 4, the refrigerant 63 is adsorbed on the nanoporous body 20 in a liquid state. When a mechanical stress is applied to the nanoporous body 20 and a work W ₂ [J] is input, the adsorbed refrigerant 63 changes to saturated vapor (state 1). The process in state 4 → 1 is an isobaric change. Therefore, the latent heat of vaporization Q _L [J] can be expressed by the following equation.

Here, w _re [kg] is the amount of the refrigerant 60 desorbed from the nanoporous body 20 by applying stress, and Δ _vap H is an enthalpy change when the refrigerant 60 undergoes a phase change from a liquid to a gas. However, w _re [kg] is the amount of the refrigerant 63 desorbed after the valve 51 of the pipe 50 connecting the first chamber 32A and the second chamber 32B is opened. As described above, this is because the latent heat of vaporization Q _L3-4 [J] generated by desorption before opening the valve 51 is used to cancel out the amount of latent heat of condensation Q _H3-4 [J]. It is because it is not used.

  The coefficient of performance COP in the reverse Carnot cycle of the present invention can be expressed by the following equation.

In Formula (5), W _ns [J] depends on the Young's modulus E [Pa] of the nanoporous body 20. Here, the definition of Young's modulus E [Pa] is as follows.

Here, the stress σ _f [Pa] is a pressure (surface pressure) acting per unit area of the nanoporous body 20. The strain ε _d is the maximum strain of the nanoporous body 20 in the most compressed state when the refrigerant 60 is desorbed from the nanoporous body 20. The definition of the stress σ _f [Pa] is as follows.

Here, F [N] is a pressure acting on the nanoporous body 20. S [m ² ] is a cross-sectional area of the nanoporous body 20. The definition of the strain ε _d is as follows.

Here, x [m] is the deformation amount of the nanoporous body 20. L ₀ [m] is the length of the nanoporous body 20 in the initial state.

Assuming that the Young's modulus E [Pa] including the refrigerant 60 does not change, W _ns can be expressed by the following equation.

Here, V ₀ [m ³ ] is an initial volume of the nanoporous body 20. Therefore, it can be transformed as the following equation.

Equation (10) is a formula for calculating the coefficient of performance COP of the present invention. In Expression (10), w _re , w _re-ads , and V ₀ can be expressed by the weight w _ns of the nanoporous body 20, respectively. In state 3, w _re-ads can be expressed by the following equation using w _ns .

Here, ρ _re [kgm ⁻³ ] is the density of the refrigerant (liquid) 60, V _ns [m ³ kg ⁻¹ ] is the pore volume of the nanoporous body 20, and φ _ns is filled with the refrigerant 60. The ratio of the pore volume to V _ns . That is, φ _ns V _ns corresponds to the volume of the pores filled with the refrigerant 60 or the volume of the refrigerant 60 filled in the pores. ρ _re φ _ns V _ns can be determined directly from the adsorption isotherm at temperature T _H.

V ₀ can be expressed by the following equation using the apparent density ρ _ns-ap [kgm ⁻³ ] of the nanoporous body 20 and the weight w _ns [kg] of the nanoporous body 20.

In any operating pressure P [kPa] with temperature _{T H,} nanoporous body 20 of the stress the absence of an applied _adsorbs refrigerant 60 _{w non-TH} [kg]. This corresponds to the state 3 in FIG.

Then, the temperature of the heat exchange portion 30A from _{T 3} to _{T 4,} switch the temperature of the heat exchange portion 30B from _{T 1} to a _{T 2.} At this time, the valve 51 between the chambers 32A and 32B is closed to prevent the movement of the vapor of the refrigerant 60 from the chamber 32B to 32A. When temperature of the heat exchange portion 30A is reduced from T ₃ to T _4, refrigerant 62 were vapor is adsorbed to the nano-porous material 20, the pressure of the gas phase decreases with latent heat of condensation Q _H3-4 occurs . Subsequently, stress is applied to the nanoporous body 20 to input work W ₁ [J], and the refrigerant 62 is desorbed. Then, latent heat of vaporization Q _L3-4 is generated and the pressure in the gas phase is increased to be in state 4. At this time, the amount of the refrigerant 60 adsorbed on the nanoporous body 20 is w _non-T3 [kg].

Next, stress is applied to the nanoporous body 20 to compress it, and the refrigerant 63 is desorbed. This corresponds to the state 1 from the state 4 in FIG. In the nanoporous body 20 after maximum compression at the temperature T ₄ (= T ₁ ), the refrigerant 60 of w _press−T1 [kg] remains and is adsorbed (state 1). Accordingly, the desorption amount w _4-1 [kg] of the refrigerant 60 in the desorption mode can be expressed by the following equation.

Next, the temperature of the heat exchange unit 30A is switched from T ₁ to T ₂ (= T ₃ ), and the temperature of the heat exchange unit 30B is switched from T ₃ to T ₄ (= T ₁ ). At this time, the valve 51 between the chambers 32A and 32B is closed to prevent the vapor of the refrigerant 60 from moving from the chambers 32A to 32B. When the temperature of the heat exchange portion 30A is increased from T ₁ to T _2, the refrigerant 62 which has been adsorbed to the nano-porous material 20 is eliminated, the pressure of the vapor phase increases with the latent heat of vaporization occurs. Subsequently, the nanoporous body 20 is freely expanded and the refrigerant 62 is adsorbed. As a result, latent heat of condensation is generated and the pressure in the gas phase is reduced, resulting in state 2. At this time, the nanoporous body 20 has adsorbed the refrigerant 60 in the amount of w _press-T1 . Therefore, the adsorption amount w _2-3 [kg] of the refrigerant 60 in the adsorption mode is given by the following equation.

_{w non-TH, w press-} TL, w press-TH _is, T L, uncompressed at _{T H,} and can be obtained from the adsorption isotherm shown in Figure 13 during compression. Here, assuming that the amount of refrigerant adsorbed on the nanoporous body 20 does not change in T _L and T _H and is simply determined by the pore volume, w _re-ads = w _non-TL = w _{non -TH,} since the _{w press = w press-TL =} w press-TH, it is possible to calculate a simplified as shown in equation (15) as _{w re = w 4-1 = w 2-3} . Under this assumption, it is possible to derive the relationship between COP and E as shown below. Note that the operating pressure P [kPa] of the present system can be selected to an arbitrary value so as to achieve a high coefficient of performance COP.

In the desorption mode, when the nanoporous body 20 is compressed and has a strain of ε _d , the pore volume of the nanoporous body 20 changes from V _ns to V _com [m ³ kg ⁻¹ ]. . On the other hand, the volume occupied by the pore walls (1 / ρ _ns ) does not change. Here, ρ _ns [kgm ⁻³ ] means the true density of the nanoporous body 20, that is, the density of the solid portion. Therefore, _Vcom is as follows.

Since w _4-1 and w _2-3 are equal, w _re can be approximated as in the following equation.

By the way, there is the following relationship between the apparent density ρ _ns-ap [kgm ⁻³ ] of the nanoporous body 20 and ρ _ns , V _ns .

  Therefore, Expression (17) becomes the following expression.

From equations (10), (11), (12) and equation (19), it can be seen that the COP of this system does not depend on the weight (w _ns ) of the nanoporous material.

  The effect of the heat exchange apparatus 10 which concerns on this embodiment demonstrated above is demonstrated.

  The heat exchanging device 10 according to the present embodiment has elasticity, can be contracted to desorb the refrigerant (medium) 60, and can expand and adsorb the medium, and the nanoporous body 20 and nanoporous It has heat exchanging parts 30A and 30B including stress applying parts 31A and 31B that apply stress to the body 20 to contract and chambers 32A and 32B that house the nanoporous body 20 therein. The heat exchanging device 10 controls the operation of the stress applying portions 31A and 31B to cause the operation mode in the heat exchanging portion to contract by applying stress to the nanoporous body 20 to remove the medium from the nanoporous body 20. It further has a control unit 40 that switches between a desorption mode for desorption and an adsorption mode for releasing the stress and expanding the nanoporous body 20 to adsorb the refrigerant 60 to the nanoporous body 20.

  According to the heat exchanging device 10, stress is applied to and released from the nanoporous body 20 to contract and expand, thereby causing the nanoporous body 20 to desorb and adsorb the refrigerant 60 to generate latent heat due to phase change. be able to. Thereby, since the latent heat generated by the desorption or adsorption of the refrigerant 60 can be directly used for cold or warm heat, an evaporator or a condenser is not necessary. In addition, since it is not necessary to reduce the pressure or heat in the evaporator or condenser in order to obtain latent heat, the energy required for the thermal cycle can be reduced. Thereby, since the coefficient of performance COP can be improved, the quantity of the nanoporous body 20 to be used can be reduced. Thus, an evaporator and a condenser become unnecessary, and since the quantity of the nanoporous body 20 can be reduced, the heat exchange apparatus 10 can be reduced in size. Since the heat exchanging device 10 can be reduced in size, it can be suitably applied particularly to a car air conditioner having a limited installation space.

  In addition, the heat exchange device 10 according to the present embodiment includes a pipe 50 that allows the refrigerant 60 to move between the pair of heat exchange units 30A and 30B and the pair of chambers 32A and 32B of the pair of heat exchange units 30A and 30B. And. The control unit 40 switches the operation mode in each of the heat exchange units 30A and 30B alternately between the adsorption mode and the desorption mode. Thereby, the latent heat of vaporization is continuously generated by alternately switching the adsorption mode and the desorption mode between the pair of heat exchange units 30A and 30B. Thereby, cold heat can be obtained efficiently.

Moreover, the Young's modulus E of the nanoporous body 20 according to the present embodiment is 1 GPa or less. Since the work W _ns [J] is reduced by reducing the stress necessary to desorb the refrigerant 60 by shrinking the nanoporous structure, the coefficient of performance COP can be increased.

  Moreover, the refrigerant | coolant (medium) 60 which concerns on this embodiment is water. The coefficient of performance COP can be further increased by using water having a high latent heat of vaporization as the refrigerant 60.

Moreover, the BET specific surface area of the porous material which forms the nanoporous body 20 which concerns on this embodiment is the range of 800-4200 m < ² > / g. By using the nanoporous body 20 having a large surface area, the adsorption amount of the refrigerant 60 can be increased. Thereby, the usage-amount of the nanoporous body 20 can be reduced.

  Further, the nanoporous body 20 according to the present embodiment is formed of zeolite template carbon (ZTC) or graphene meso sponge (GMS). Thus, by applying and releasing stress to the nanoporous body 20 to cause contraction and expansion, the nanoporous body 20 can be surely desorbed and adsorbed to generate latent heat due to phase change.

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the technical scope of the present invention is not limited only to the following examples.

[Example 1]
(Preparation of ZTC)
ZTC according to this example was synthesized with reference to Nishihara, H. et al., Chemistry-European Journal 15, 5355 (2009). Zeolite X (Union Showa, 13X) was placed in an electric furnace and heated to 873 K in a nitrogen stream. When it reached 873 K, nitrogen was switched to 20 vol% acetylene 80 vol% nitrogen, and chemical vapor deposition (CVD) was performed for 4 hours to deposit carbon in the zeolite X pores. Thereafter, the flow was switched to a nitrogen-only flow, and the temperature was increased to 1123K and held for 3 hours. After cooling the sample to room temperature, zeolite X was removed with hydrofluoric acid (47 wt%, Wako pure chemical industries) to obtain ZTC.

<Volume modulus and elastic properties of ZTC>
An experiment was conducted to measure the volume modulus of elasticity of the ZTC prepared in Example 1 and confirm the elastic properties. As a comparative example, activated carbon (Shirasagi-P, Japan EnviroChemicals, Ltd.) was used.

(Measurement of bulk modulus)
Example 1 and the comparative example were subjected to an isostatic mercury test to measure a stress-volume strain curve. The bulk modulus was calculated from the obtained stress-volume strain curve. The mercury isotropic pressure test is a test for measuring the relationship between compressive stress and pore volume by an mercury intrusion method using a mercury porosimeter (Micromerit-ics Instrument Corporation, Autopore IV 9510) under an isotropic pressure press. . Specifically, the samples of Example 1 and Comparative Example that were previously vacuum-treated were set in a sealed chamber, and mercury was introduced into the chamber under vacuum. The volume V _Hg [m ³ ] when mercury spreads over the entire sample at a stress (isotropic pressure) P [MPa] was measured. FIG. 8 shows the relationship between the stress P [MPa] and the volumetric strain V _Hg / V ₀ of the pores.

As shown in FIG. 8, when the stress is 20 MPa or less, V _Hg rapidly decreases because mercury penetrates the particle gap. The bulk modulus K [MPa] of the sample was calculated from a linear approximation of a stress-volume strain curve when the stress was 50 to 150 MPa. The linear approximation formula can be expressed by the following formula.

Here, V ₀ [m ³ ] is an initial pore volume.

  The phenomenon occurring at 50 MPa or more was assumed to be deformation of the pores due to mechanical compression, and the volume modulus was calculated from the above linear approximation formula. The volume modulus of elasticity of ZTC of Example 1 was 0.70 GPa. The volume modulus of the activated carbon of the comparative example was 1.7 GPa. In addition, since activated carbon has large pores, it may be underestimated.

  Assuming that ZTC is an isotropic homogeneous elastic body, the relationship between the bulk modulus K [MPa] and the Young's modulus E [Pa] can be expressed by the following equation.

(Elastic properties)
The ZTC single particles prepared in Example 1 and the activated carbon single particles according to the comparative example were used as samples. FIG. 9 shows a result of observing a change in shape when a compressive stress is applied to the sample and then released. Specifically, the sample was placed on an aluminum substrate, compressed with a tungsten probe in the SEM apparatus, and single particle deformation was observed in situ. Subsequently, the probe was separated from the particles, and the state where the single particles were restored was observed.

  The shapes of the ZTC particles and the activated carbon particles were observed with SEM (Hitachi, S-4800). SEM (AD Science, PS4-2MM2LC-TH) was used for in situ observation of particle deformation by applying stress to single particles. The tip of a tungsten probe (GGB Industries, PT-14-6705-B) was cut in advance and flattened in advance using a Ga-focused ion beam device (FEI, Helios NanoLab 600i).

  As shown in FIG. 9, it was confirmed that the shape of ZTC was reversibly deformed by applying compressive stress (about 30% compression) and releasing. On the other hand, activated carbon was easily broken by the same compression and did not show a reversible shape change.

<Measurement of water desorption and adsorption during stress application>
An experiment was conducted to confirm the desorption and adsorption of water when a stress was applied to the ZTC prepared in Example 1. FIG. 10 shows a press chamber apparatus for measuring the amount of desorption and adsorption of water when stress is applied to or released from a sample in a sealed chamber. A linear introduction machine is connected to the chamber of the press chamber apparatus so that stress can be applied to the sample within the sealed chamber.

  First, the ZTC particles prepared in Example 1 were mixed with 5% by weight of a Teflon (registered trademark) binder to form a sheet-like sample. The sample was vacuum-dried at 423K and set in a chamber for in situ measurement of a press chamber apparatus. The chamber was fastened to an automatic gas adsorption device (BEL Japan, BELSORB-max) so that the internal pressure of the chamber could be monitored. In order to secure a sufficient amount of sample for measurement, the sheet-like sample was set in the chamber in such a manner that it was sandwiched and laminated between stainless steel metal plates. Prior to the in situ measurement, the laminated sample was pressed several times to stabilize the elastic deformation of the sample.

  The relationship between the torque of the linear introduction machine and the stress applied to the laminated sample was confirmed in advance by another experiment described below. A ratchet (Kyoto Tool Co., GEK085-W36) with a torque sensor attached thereto was attached to the linear introduction machine so that the torque for turning the linear introduction machine could be measured. The ratchet was turned in a state where the tip portion of the straight-line introduction machine was fixed so as to contact the load cell of the test machine (Shimadzu, AG-50kNXplus), and the relationship between the torque applied to the handle and the stress applied to the load cell was examined. By using the above relationship, the stress applied to the stacked samples was controlled by the torque of the linear introduction machine.

  FIG. 11 shows the measurement results of the desorption / adsorption isotherm of water in the stressed state and the stressless state at 298 K for ZTC of Example 1 and the activated carbon of the comparative example. Here, the stress applied to the ZTC of Example 1 was 83 MPa, and the stress applied to the activated carbon of the comparative example was 120 MPa.

From the results shown in FIG. 11, at a relative pressure P / P ₀ = 0.94 (P: water vapor pressure, P ₀ : saturated water vapor pressure), the 83 MPa stress application state of Example 1 is more water than the no stress application state. It was confirmed that the amount of adsorbed was reduced by about 31%. This is presumably because the pore volume was reduced by 31% due to the deformation of ZTC. ZTC pores exist in the gaps of graphene arranged periodically at intervals of 1.4 nm. When ZTC is deformed, the pore diameter decreases, but the graphene thickness remains unchanged. For this reason, when the pores shrink by 31%, it can be estimated that the entire ZTC has a strain of 23%. On the other hand, regarding the activated carbon of the comparative example, even in the stress applied state of 120 MPa, no change was observed in the amount of adsorption compared to the state in which no stress was applied. This result is because activated carbon does not have flexibility.

<Confirmation of water desorption / adsorption and phase change>
Next, an experiment was conducted to confirm that desorption / adsorption of water and phase change of water (liquid) / water vapor occurred by applying / releasing stress to the ZTC of Example 1. First, water vapor (relative pressure P / P ₀ = 0.69) was introduced into a 298K chamber in which the ZTC of Example 1 in a state in which no stress was applied was disposed. After the pressure decrease disappeared and equilibrium was reached, stress up to 80 MPa was applied to the ZTC to desorb water vapor, and the pressure in the chamber was monitored. After 10 minutes, the stress was released and the ZTC was allowed to expand freely and left for 10 minutes. The stress application / release cycle was performed four times. FIG. 12 shows the result of measuring the change in water vapor pressure in the chamber when applying and releasing stress repeatedly. The decrease in dead volume due to stress application was 0.13 cm ³ , confirming that it was only 0.2% of the total volume (59 cm ³ ). This is only 0.0014 in the increase in the relative pressure P / _{P 0.} Therefore, the increase (about 0.09) in the relative pressure P / P ₀ observed in FIG. 12 is considered to be due to water vapor generated by forced desorption of adsorbed water by a mechanical press.

Subsequently, a test was conducted in which the adsorbed water was changed into water vapor by mechanical stress. In advance, water vapor was introduced into the chamber, and water vapor was adsorbed on the ZTC at a relative pressure P / P ₀ = 0.69. Subsequently, when 83 MPa was applied to the ZTC sheet, the water vapor pressure in the chamber rose to 0.79 ((i) in FIG. 12). It has been confirmed in advance that the decrease in dead volume caused by this compression is negligibly small.

  Subsequently, when the stress was released, the water vapor pressure decreased ((ii) in FIG. 12). This means that the ZTC freely expanded and returned to its original shape, and the vacancies recovered and the water vapor was adsorbed again. It is shown that.

  It was also revealed that water can be reversibly desorbed / adsorbed by applying / releasing stress ((iii) in FIG. 12). From this result, it was confirmed that the water / water vapor phase transition due to stress application / release was reversible, and ZTC could be applied as the nanoporous material 20 according to the present invention.

<Relationship between physical adsorption amount of ZTC and temperature>
FIG. 13 shows two water adsorption isotherms measured at 298 K (T _L ) and 303 K (T _H ) for the ZTC of Example 1, and the adsorption isotherm when ZTC is compressed at 83 MPa at these two temperatures. It is the figure which showed the prediction of the line. Point I in FIG. 13 is a water adsorption isotherm of ZTC in a stress-free state measured at 298K. Point IV in FIG. 13 is a water adsorption isotherm of ZTC in a stress-free state measured at 303K.

  Points II and III are values obtained by correcting the actual measurement value of the water adsorption isotherm at point I and point IV to 69%, and reproducing the water adsorption isotherm in a stress application state of 83 MPa. Point II in FIG. 13 is a water adsorption isotherm of ZTC in a stress application state of 298 K and 83 MPa. Point III in FIG. 13 is a water adsorption isotherm of ZTC in a stress application state of 83 MPa at 303K. In addition, at a water vapor pressure of 2.9 kPa, the amount of adsorption of the ZTC at 83 MPa in the stress-applied state decreases to 69% of the amount of adsorption in the non-stressed state. It confirmed from the measurement result of the isotherm.

<Calculation of coefficient of performance COP>
The water adsorption isotherm of FIG. 13 and the calculation formulas of the coefficient of performance COP shown above (Formula (10)), Formula (11), Formula (12), Formula (13), Formula (17), and Formula (19) Was used to calculate the coefficient of performance COP when operating the heat exchange device 10 with the ZTC as the nanoporous body 20.

The operating conditions were T _H = 303K, T _L = 298K, and P = 2.9 kPa. In addition, a stress of 83 MPa is applied to ZTC.

  FIG. 14 is a measurement result of a stress strain curve obtained using a ZTC / PTFE sheet. Using this data, the COP at a water vapor pressure of 2.9 kPa can be calculated based on equation (10).

In this equation, Δ _vap H = 2453 kJkg ⁻¹ and c _re = 4.184 kJkg ⁻¹ K ⁻¹ , respectively. The temperature difference (T _H −T _L ) between the high temperature side and the low temperature side is 5K. c _ns was set to 0.72 kJkg ⁻¹ K ⁻¹ using the value of graphite. From the equation _(12), a _{V 0 = w ns / ρ ns} -ap = 0.001976w ns. Furthermore, the Young's modulus of the ZTC sheet is determined to be 0.38 GPa from the stress-strain curve separately measured during the in situ measurement in FIG. Therefore, the strain ε _d when 83 MPa is applied is 0.23. w _re-ads can be represented by w _ns , and the amount of adsorption of the nanoporous material 20 in the state where stress is not applied at the temperature T _H = 303 K shown in the point I (51.1 mmolg ⁻¹ = 0.92 kgkg ⁻¹ ) from w _ns, the w re-ads = 0.92w _ns.

As shown in Expression (15), w _re is a difference between w _re-ads and w _press-TL . w _press-TL, the adsorption amount of ZTC sheet obtained by compressing at a temperature _T L = 298K shown in point II in FIG. 13 (42.8mmolg ^-1 = 0.77kgkg ^-1) from _{w ns,} be expressed as 0.77 W _ns Can do. _Therefore, the _{w re = 0.92w ns -0.77w ns =} 0.15w ns.

From the area of the hatched portion in FIG. 14, the energy loss φ _f [J] due to the internal friction of ZTC can be calculated and is 0.34. Since energy loss becomes heat and raises the temperature of the room to be cooled, the loss is deducted. The COP at T _H = 303K, T _L = 298K, and P = 2.9 kPa can be obtained by substituting the numerical values shown above into Equation (10), and is calculated as 17.2.

Then, to calculate the approximate relationship between the strain ε _d and the coefficient of performance COP. In the equation (10), it is assumed that Δ _vap H = 2453 kJkg ⁻¹ , c _re = 4.184 kJkg ⁻¹ K ⁻¹ , T ₃ −T ₄ = 20K. The value of c _ns can be assumed to be 0.72 kJkg ⁻¹ K ⁻¹ as the value of graphite. Therefore, Formula (10) can be expressed by the following formula.

  Substituting Equation (11), Equation (12), and Equation (19) gives the following equation.

In equation (21), ρ _re , φ _ns , and V _ns can be determined from an adsorption isotherm (see point IV in FIG. 13) at temperature T ₃ . ρ _re is 1000 kgm ⁻³ , and ρ _ns-ap is about 1000 kgm ⁻³ at most in a general pore material. V _ns is at most about 0.003 m ³ kg ⁻¹ . Assume that φ _ns is 1. From the above, the coefficient of performance COP, using the strain epsilon _d and Young's modulus E, can be approximated by the formula (24).

FIG. 15 is a diagram showing an approximate curve between the coefficient of performance COP of the heat exchange device 10 obtained by the equation (24) and the Young's modulus E depending on the strain amount ε _d of the nanoporous body 20. The approximate curve was calculated using the equation (24) described above. The smaller the strain ε _d is, the larger the coefficient of performance COP is. On the other hand, the smaller the strain ε _d is, the more the volume of the nanoporous body 20 is increased. As a result, the heat exchange device 10 is increased in size. Therefore, the strain ε _d is preferably 0.2 or less. As shown in FIG. 15, the strain epsilon _d is the coefficient of performance COP 10 or more 0.2 or less condition, the Young's modulus E of the nanoporous material 20 must be less than or equal to 1.1 GPa. For the above reasons, the Young's modulus E of the nanoporous body 20 is preferably designed to be 1.1 GPa or less.

[Example 2]
Example 2 shows an example in which GMS is used as the nanoporous body 20 and ethanol is used as the refrigerant 60 in the heat exchange device 10.

(Preparation of GMS)
GMS has a single-layer graphene skeleton and has a large porosity and elasticity. For the synthesis method of GMS, Advanced Functional Materials, Vol. 26, 2016, 6418-6427.

  Alumina nanoparticles (Taimei Chemicals, TM300) were placed in an electric furnace and heated to 1173K in a nitrogen stream. When reaching 1173K, the nitrogen gas was switched to 20 vol% methane and 80 vol% nitrogen, and carbon was deposited on the surface of the alumina nanoparticles by CVD for 2 h. Then, it switched to the flow only of nitrogen and cooled to room temperature. The obtained carbon-coated alumina nanoparticles were immersed in hydrofluoric acid (47 wt%, Wako pure chemical industries) to remove the alumina nanoparticles. The obtained mesoporous carbon was baked at 2073 K in an argon stream (10 Pa) to obtain GMS.

GMS is mainly composed of single-layer graphene and has great elasticity. FIG. 16 shows ethanol desorption / adsorption curves when no GMS stress was applied and when 90 MPa stress was applied (298 K). The amount of adsorption at P / P ₀ = 0.92 was reduced to 58% with the application of stress. Assuming that the true density of GMS is 2.0 g / cm ³ for a typical carbon material, the total pore volume is 2.79 cm ³ / g. Using these values, the deformation amount as a whole GMS is calculated as 36%.

  FIG. 17 shows the result of applying stress to GMS during the desorption measurement when measuring the ethanol desorption / adsorption isotherm (298K) in GMS. The adsorption is completed and a desorption point indicated by point A in FIG. 17 is observed. When 90 MPa is applied to GMS immediately after the measurement of point A is completed, the next measurement point becomes point B. That is, the relative pressure increased from point A to point B. From this result, also in the heat exchange apparatus 10 of Example 2, it confirmed that the phase change (liquid-> gas) had occurred at the time of stress application. The above results show that GMS can also be applied as the nanoporous body 20 according to the present invention.

[Second Embodiment]
FIG. 18 is a schematic cross-sectional view showing the configuration of the heat exchange device 100 according to the second embodiment. The stress applying unit 200 of the heat exchange device 100 is used to contract the repulsive stress caused by the expansion of the nanoporous body in one heat exchange unit in the adsorption mode and the nanoporous body in the other heat exchange unit in the desorption mode. It differs from 1st Embodiment mentioned above by the point which has the stress conversion part 230 converted into stress. Since the configuration other than the stress applying unit 200 is the same as that of the first embodiment described above, the same reference numerals are given and description thereof is omitted.

  In the heat exchange device 10 according to the first embodiment, two stress applying portions 31A and 31B are respectively attached to the two chambers 32A and 32B, and the two stress applying portions 31A and 31B are independently controlled to be 2 Stress was applied to and released from the two nanoporous bodies 20A and 20B. In the heat exchange device 100 according to the second embodiment, one stress applying unit 200 is attached to the two chambers 32A and 32B, and the two nanoporous bodies 20A and 20B are controlled by controlling the one stress applying unit 200. Stress and release.

  The heat exchange device 100 performs a swing operation so that the other operation mode is the adsorption mode while one operation mode of the pair of heat exchange units 30A and 30B is the desorption mode. Therefore, when the heat exchange apparatus 100 compresses the nanoporous bodies 20A and 20B in one chamber 32A and 32B by applying stress to the nanoporous bodies 20A and 20B in the other chambers 32A and 32B, Release the stress and let it expand freely.

  The first chamber 32A and the second chamber 32B are arranged symmetrically with respect to the center plane C. Hereinafter, the configuration of the stress applying unit 200 will be described in detail.

  The stress applying unit 200 includes a cylindrical cylinder 210, two pistons 220A and 220B movable within the cylinder 210, a stress converting unit 230 connecting the two pistons 220A and 220B, and press units 240A and 240B. And have. The press parts 240A and 240B are fixed to the two pistons 220A and 220B, respectively, and apply and release stress to the nanoporous bodies 20A and 20B.

  The stress conversion unit 230 includes a first link member 231 that rotates around the fixed axis O1, a second link member 232 that is coupled to the piston 220A, and a third link member 233 that is coupled to the piston 220B. The stress conversion unit 230 further includes a connecting portion 234 that connects the first link member 231, the second link member 232, and the third link member 233. The fixed axis O1 is disposed on the center plane C. The connecting portion 234 has a movable shaft O2 that is rotatable around the fixed shaft O1.

  One end of the first link member 231 is fixed to the fixed shaft O1 so as to be rotatable around the fixed shaft O1. The other end of the first link member 231 is connected to the connecting portion 234 so as to be rotatable around the movable axis O2.

  One end of the second link member 232 is coupled to the piston 220A so as to be rotatable around a first axis O3 fixed to the piston 220A. The other end of the second link member 232 is connected to the connecting portion 234 so as to be rotatable around the movable axis O2. Similarly, one end of the third link member 233 is coupled to the piston 220B so as to be rotatable around a second axis O4 fixed to the piston 220B. The other end of the third link member 233 is connected to the connecting portion 234 so as to be rotatable around the movable axis O2.

  19A to 19D are schematic cross-sectional views for explaining the operation of the heat exchange device 100 according to the second embodiment. The operation of the stress applying unit 200 is controlled by the control unit 40.

  FIG. 19A is a diagram illustrating a state corresponding to FIGS. 6A, 6G, and 6H according to the first embodiment. FIG. 19B is a diagram illustrating a state corresponding to FIG. 6B of the first embodiment. FIG. 19C is a diagram illustrating a state corresponding to FIGS. 6C, 6D, and 6E of the first embodiment. FIG. 19D is a diagram illustrating a state corresponding to FIG. 6F of the first embodiment. The operation modes of the heat exchange units 30A and 30B corresponding to the respective states are the same as those in the first embodiment described above, and thus the description thereof is omitted.

  In FIG. 19A, the first nanoporous body 20A in the first chamber 32A is in a state of free expansion without application of stress from the stress applying unit 200. The second nanoporous body 20 </ b> B in the second chamber 32 </ b> B is in a contracted state due to the application of stress from the stress applying unit 200. The distance L1 from the first axis O3 to the center plane C is shorter than the distance L2 from the second axis O4 to the center plane C.

  When the first link member 231 is rotated counterclockwise around the fixed axis O1 from the state of FIG. 19A, the connecting portion 234 moves to the first chamber 32A side. As the connecting portion 234 moves, the second link member 232 and the third link member 233 move to the first chamber 32A side. As a result, the two pistons 220A and 220B move to the first chamber 32A side.

As the piston 220B moves, the stress is gradually released from the second nanoporous body 20B in the second chamber 32B. Thereby, the second nanoporous body 20B is freely expanded. The repulsive stress due to free expansion of the second nanoporous body 20B is transmitted to the second link member 232 via the press part 240B, the piston 220B, and the third link member 233. The second link member 232 uses the repulsive stress as a stress for compressing the first nanoporous body 20A in the first chamber 32A. That is, the stress conversion unit 230 converts the repulsive stress caused by the free expansion of the second nanoporous body 20B into mechanical energy W _rns [J] for compressing the first nanoporous body 20A.

  When the first link member 231 is rotated 90 degrees counterclockwise about the fixed axis O1 from the state of FIG. 19A, the state of FIG. 19B is obtained. In FIG. 19B, the movable axis O2 is disposed on the center plane C. In this state, the distance L1 from the first axis O3 to the center plane C is equal to the distance L2 from the second axis O4 to the center plane C.

  When the first link member 231 is further rotated 90 degrees counterclockwise around the fixed axis O1 from the state of FIG. 19B, the connecting portion 234 is further moved to the first chamber 32A side to be in the state of FIG. 19C. A distance L1 from the first axis O3 to the center plane C is longer than a distance L2 from the second axis O4 to the center plane C. Thereby, the first nanoporous body 20A in the first chamber 32A is in the most compressed state, and the second nanoporous body 20B in the second chamber 32B is released from the stress.

When the first link member 231 is further rotated counterclockwise around the fixed axis O1 from the state of FIG. 19C, the connecting portion 234 moves to the second chamber 32B side. As in the case of FIGS. 19A and 19B, the stress conversion unit 230 is configured to generate mechanical energy W _rns [J ].

  When the first link member 231 is rotated 90 degrees counterclockwise around the fixed axis O1 from the state of FIG. 19C, the state of FIG. 19D is obtained. In FIG. 19D, the movable axis O2 is disposed on the center plane C. In this state, the distance L1 from the first axis O3 to the center plane C is equal to the distance L2 from the second axis O4 to the center plane C.

As described above, in the control of the heat exchange device 100, the operation shown in FIGS. 19A to 19D is repeated, and the operation modes of the pair of heat exchange units 30A and 30B are alternately swung. Accordingly, it is possible to continuously generate cold heat due to the latent heat of vaporization Q _L [J] in the heat exchange units 30A and 30B in the desorption mode. Further, the stress conversion unit 230 can recover the repulsive stress due to the free expansion of the nanoporous bodies 20A and 20B by converting the repulsive stress into mechanical energy W _rns [J] for operating the heat exchange device 100.

The base of the COP calculation formula is as shown in Formula (5), but as shown in FIGS. 19A to 19D, the stress conversion unit 230 has a repulsive stress due to free expansion at the time of stress release of the nanoporous bodies 20A and 20B. Can be recovered as the recoverable mechanical energy W _rns [J], it can be subtracted from the energy to be added as the denominator, and therefore can be expressed by the equation (25).

As shown in FIG. 20, the recoverable mechanical energy W _rns [J] accompanying the repulsive stress due to free expansion at the time of release of the nanoporous bodies 20A and 20B is obtained from the hysteresis of the stress-strain curve of the nanoporous body. Can be obtained. Further, the lost energy can be obtained by subtracting the amount lost by the internal friction Q _f [J]. In addition, FIG. 20 is a figure showing the stress-strain curve of the nanoporous body measured on the same conditions as FIG.

  Substituting equation (28) into equation (25) yields:

  Substituting into the equations (3) to (9), the COP calculation formula of the system for recovering the repulsive stress becomes the form shown in the equation (30).

In this equation, the same conditions as in Example 1, Δ _vap H = 2453 kJkg ⁻¹ , c _re = 4.184 kJkg ⁻¹ K ⁻¹ , temperature difference between the high temperature side and the low temperature side (T _H −T _L ) = 5K , C _ns = 0.72 kJkg ⁻¹ K ^−1, and the Young's modulus of the ZTC sheet is 0.38 GPa from the stress-strain curves (FIGS. 14 and 20) separately measured during the in situ measurement of FIG. Is required. Therefore, the strain ε _d when 83 MPa is applied is 0.23, and the adsorption amount of the nanoporous body 20 in the stress-free state at the temperature T _H = 303 K indicated by the point I (51.1 mmolg ⁻¹ = 0.92 kgkg ⁻ from ¹⁾ _{w ns,} from w re-ads = 0.92w _ns, adsorption of ZTC sheet obtained by compressing at a temperature _T L = 298K shown in point ^{II (42.8mmolg -1 = 0.77kgkg -1)} w ns, since the _{0.77w ns, w re = 0.92w ns} -0.77w ns = 0.15w ns, from the area of the hatched portion in FIG. 14, [J] energy loss _phi f due to internal friction ZTC calculates it can, substituting 0.34, respectively, put _T H ₌ 303 K is a condition of FIG. 13, T L = 298K, the P = 2.9kPa Can calculate the COP in a system for recovering repulsive stress, its COP is improved to 17.2 from 50.6 in Example 1.

As described above, the stress applying unit 200 of the heat exchange device 100 according to the present embodiment desorbs the repulsive stress caused by the expansion of the nanoporous bodies 20A and 20B of the one heat exchange unit 30A and 30B in the adsorption mode. It further has a stress conversion unit 230 that converts the nanoporous bodies 20A and 20B of the other heat exchange units 30A and 30B of the mode into stress for contraction. The stress conversion unit 230 converts the repulsive stress caused by the free expansion of one nanoporous body 20A, 20B into mechanical energy W _rns [J] for compressing the other nanoporous body 20A, 20B. As a result, the rebound stress of free expansion of the nanoporous bodies 20A and 20B can be efficiently recovered.

[Modification of Second Embodiment]
The configuration of the heat exchange device including the stress conversion unit is not limited to the form shown in FIG. 18 and can be changed as appropriate. For example, in the embodiment shown in FIG. 18, an example is shown in which the stress conversion section and the chambers 32A and 32B are fastened horizontally, but a similar effect can be obtained even in a system fastened to a V shape as shown in FIG.

  Moreover, although the example which combined two chambers is shown in FIG. 18, FIG. 21, the same effect is acquired even if it combines three chambers or four or more chambers as needed.

  As mentioned above, although the heat exchange apparatus which concerns on embodiment of this invention was demonstrated, this invention is not limited to embodiment mentioned above. The present invention can be modified in various ways based on the configurations described in the claims, and these are also within the scope of the present invention.

  For example, the case where the heat exchange device of the present invention is applied to a cooling device (refrigerator) that cools an object using cold heat obtained from the latent heat of vaporization during desorption has been described as an example. You may apply to the heating apparatus (heat pump) which heats object using the heat obtained from condensation latent heat.

  Moreover, although demonstrated as a batch-type heat exchange apparatus which has a pair (two) heat exchange part, it is not limited to this, You may comprise by one heat exchange part, and three or more heat exchange parts You may comprise by.

10, 100 heat exchange device,
20 Nanoporous material,
20A first nanoporous body,
20B second nanoporous body,
30A 1st heat exchange part (heat exchange part),
31A 1st stress application part (stress application part),
32A first chamber (chamber),
30B 2nd heat exchange part (heat exchange part),
31B 2nd stress provision part (stress provision part),
32B Second chamber (chamber),
33A 1st air conditioning part,
33B 2nd air conditioning part,
40 control unit,
50 piping,
51 valves,
60 refrigerant (medium),
200 stress applying part,
210 cylinders,
220A, 220B piston,
230 stress converter,
231 first link member,
232 second link member,
233 third link member,
234 connecting part,
240A, 240B Press part.

Claims (7)

A nanoporous body having elasticity, capable of shrinking and desorbing the medium, and capable of expanding and adsorbing the medium;
A stress applying portion for applying stress to the nanoporous body to cause contraction;
A chamber containing the nanoporous body therein;
A heat exchange section comprising:
An operation mode in the heat exchange unit by controlling the operation of the stress applying unit, and a desorption mode in which the medium is desorbed from the nanoporous body by applying stress to the nanoporous body to contract A controller that switches to an adsorption mode that releases the stress and expands the nanoporous body to adsorb the medium to the nanoporous body;
A heat exchange device. A pair of said heat exchange parts;
A pipe through which the medium is movably communicated between the chambers of the pair of heat exchange units;
Further comprising
The heat exchange device according to claim 1, wherein the control unit switches an operation mode in each of the heat exchange units alternately between the adsorption mode and the desorption mode.   The stress applying portion contracts the repulsive stress due to the expansion of the nanoporous body in one of the heat exchange portions in the adsorption mode, and the nanoporous body in the other heat exchange portion in the desorption mode. The heat exchange device according to claim 2, further comprising a stress conversion unit that converts the stress into a stress.   The heat exchange apparatus according to any one of claims 1 to 3, wherein the Young's modulus of the nanoporous material is 1.1 GPa or less.   The heat exchanger according to any one of claims 1 to 4, wherein the medium is water. The heat exchange apparatus according to any one of claims 1 to 5, wherein a BET specific surface area of the porous material forming the nanoporous body is in a range of 800 to 4100 m ² / g.   The heat exchange apparatus according to any one of claims 1 to 6, wherein the nanoporous body is formed of zeolite template carbon (ZTC) or graphene meso sponge (GMS).