Heat absorption and dissipation system

Abstract

A heat absorption / release system according to the present disclosure uses a heat medium that contains a rubidium-manganese-iron cyano complex. This heat absorption / release system applies a pressure to the heat medium so that the rubidium-manganese-iron cyano complex undergoes a phase transition from a high-temperature phase to a low-temperature phase, thereby causing the heat medium to release heat; and this heat absorption / release system releases the applied pressure from the heat medium so that the rubidium-manganese-iron cyano complex undergoes a phase transition from a low-temperature phase to a high-temperature phase, thereby causing the heat medium to absorb heat. This heat absorption / release system repeats application and release of a pressure to the heat medium. Consequently, the present disclosure enables efficient absorption and release of heat by effectively utilizing the characteristics of a rubidium-manganese-iron cyano complex.

Description

[Technical field]

[0001] The present disclosure relates to a heat absorption / dissipation system that uses a heat medium containing a rubidium-manganese-iron cyano complex. [Background technology]

[0002] Rubidium-manganese-iron cyanide complex (Rb x Mn[Fe(CN)6] y ) is known (see, for example, Non-Patent Document 1). Such a rubidium-manganese-iron cyano complex exhibits bistability in two states: a high-temperature phase in which the valences of manganese and iron are Mn(II)-Fe(III) and a low-temperature phase in which the valences of manganese and iron are Mn(III)-Fe(II). When heated to a first temperature or higher, the complex undergoes a phase transition from the low-temperature phase to the high-temperature phase, absorbing heat, and when heated to a second temperature or lower, which is lower than the first temperature, the complex undergoes a phase transition from the high-temperature phase to the low-temperature phase, releasing heat. Furthermore, Non-Patent Document 1 discloses that when the rubidium-manganese-iron cyano complex is pressurized, the phase transition temperatures from the high-temperature phase to the low-temperature phase and from the low-temperature phase to the high-temperature phase increase.

[0003] Also, a heat storage and dissipation system using a heat storage body containing the rubidium-manganese-iron cyano complex is known (for example, see Patent Document 1). This heat storage and dissipation system includes an insulating case that houses the heat storage body, an opening / closing device that opens and closes the opening of the insulating case, a first heat transfer section that thermally connects the heat generating body and the heat storage body and is switchable between a heat transfer state and a non-heat transfer state, a second heat transfer section that thermally connects the heated object and the heat storage body and is switchable between a heat transfer state and a non-heat transfer state, and a control section. When the temperature of the heat generating body is equal to or higher than a first temperature, the control section closes the opening and puts the first heat transfer section into a heat transfer state. When the outside air temperature around the insulating case is equal to or lower than a second temperature and a specified start condition for the heated object is satisfied, the control section opens the opening and puts the second heat transfer section into a heat transfer state. As a result, when the temperature of the heating element is equal to or higher than the first temperature, the heat of the heating element is transferred to the heat storage element, and the heat storage element (rubidium-manganese-iron cyano complex) undergoes a phase transition to a high-temperature phase to store the heat. Also, when the outside air temperature is equal to or lower than the second temperature and the start condition is satisfied, the heat storage element is cooled to equal to or lower than the second temperature by the outside air flowing into the thermally insulated case from the opening, and the heat storage element (rubidium-manganese-iron cyano complex) undergoes a phase transition to a low-temperature phase to release heat, and the object to be heated can be heated by the heat released from the heat storage element. [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] JOURNAL OF APPLIED PHYSICS 109, 013520 (2011) [Patent Document 1] JP 2020-200799 A Summary of the Invention [Problem to be solved by the invention]

[0005] According to the heat storage and dissipation system described in the above Patent Document 2, it is possible to efficiently absorb heat from a heating body and store it in a heat storage body with a relatively simple configuration, and to heat an object to be heated by dissipating the stored heat from the heat storage body as necessary. However, in the above heat storage and dissipation system, the rubidium-manganese-iron cyano complex is used only to store the heat absorbed from the heating body and dissipate the stored heat to heat an object to be heated, and the properties of the rubidium-manganese-iron cyano complex disclosed in Non-Patent Document 1 are not fully utilized.

[0006] Therefore, a primary object of the present disclosure is to provide a heat absorption / dissipation system that can efficiently absorb and release heat by effectively utilizing the properties of a rubidium-manganese-iron cyano complex. [Means for solving the problem]

[0007] The heat absorption and release system of the present disclosure is a heat absorption and release system that uses a heat medium containing a rubidium-manganese-iron cyano complex, and applies pressure to the heat medium to cause a phase transition of the rubidium-manganese-iron cyano complex from a high-temperature phase to a low-temperature phase, thereby releasing heat from the heat medium, and releases the pressure applied to the heat medium to cause a phase transition of the rubidium-manganese-iron cyano complex from a low-temperature phase to a high-temperature phase, thereby causing the heat medium to absorb heat, and repeatedly applies and releases pressure to the heat medium.

[0008] The heat absorption and dissipation system of the present disclosure applies pressure to a heat medium containing a rubidium-manganese-iron cyano complex, and causes the rubidium-manganese-iron cyano complex to undergo a phase transition from a high-temperature phase to a low-temperature phase, thereby releasing heat from the heat medium. That is, when pressure is applied to the rubidium-manganese-iron cyano complex, the phase transition temperature from the high-temperature phase to the low-temperature phase and the phase transition temperature from the low-temperature phase to the high-temperature phase increase. Therefore, by applying pressure to the heat medium, the phase transition temperature from the high-temperature phase to the low-temperature phase, which is lower than the phase transition temperature from the low-temperature phase to the high-temperature phase, increases, so that the rubidium-manganese-iron cyano complex can undergo a phase transition from the high-temperature phase to the low-temperature phase, thereby releasing heat from the heat medium, without significantly lowering the temperature of the heat medium. In addition, the present inventors have confirmed that when the pressure applied to the rubidium-manganese-iron cyano complex is released, the phase transition temperature from the high-temperature phase to the low-temperature phase and the phase transition temperature from the low-temperature phase to the high-temperature phase decrease. Therefore, by releasing the pressure applied to the heat medium, it is possible to cause the rubidium-manganese-iron cyano complex to undergo a phase transition from a low-temperature phase to a high-temperature phase without significantly increasing the temperature of the heat medium. Furthermore, by repeatedly applying and releasing pressure to the heat medium, heat can be transferred from a low-temperature portion to a high-temperature portion via the heat medium. As a result, it is possible to realize a heat absorption and release system that effectively utilizes the properties of the rubidium-manganese-iron cyano complex to efficiently absorb and release heat and function as a heat pump. [Brief description of the drawings]

[0009] [Figure 1] 1 is a schematic diagram showing an example of a heat absorption and dissipation system according to the present disclosure; [Diagram 2] 1 is a diagram showing the relationship between temperature and magnetic susceptibility of the rubidium-manganese-iron cyanide complex. [Diagram 3] 1 is a diagram showing the relationship between the temperature of a rubidium-manganese-iron cyano complex and the amount of heat obtained by a differential scanning calorimeter. [Figure 4] 4A, 4B, 4C, 4D, 4E, 4F and 4G are explanatory diagrams showing the relationship between the pressure applied to a rubidium-manganese-iron cyano complex and the phase transition temperature. [Diagram 5]1 is a graph showing the relationship between the amount of cobalt doped into a rubidium-manganese-iron cyano complex and the phase transition temperature of the rubidium-manganese-iron cyano complex. [Figure 6] FIG. 2 is a schematic configuration diagram for explaining the operation of the heat absorption and dissipation system shown in FIG. [Figure 7] FIG. 2 is a schematic configuration diagram for explaining the operation of the heat absorption and dissipation system shown in FIG. [Figure 8] FIG. 2 is a schematic configuration diagram for explaining the operation of the heat absorption and dissipation system shown in FIG. [Figure 9] FIG. 2 is a schematic configuration diagram for explaining the operation of the heat absorption and dissipation system shown in FIG. [Figure 10] FIG. 11 is a schematic configuration diagram showing another example of a heat absorption and dissipation system according to the present disclosure. [Figure 11] 1 is a graph showing the relationship between the amount of divalent metal ions doped into a rubidium-manganese-iron cyano complex and the phase transition temperature of the rubidium-manganese-iron cyano complex. [Figure 12] 1 is a graph showing the relationship between the amount of divalent metal ions doped into a rubidium-manganese-iron cyano complex and the hysteresis width of the phase transition temperature of the rubidium-manganese-iron cyano complex. [Figure 13] FIG. 11 is a schematic configuration diagram showing still another example of the heat absorption and dissipation system of the present disclosure. [Figure 14] FIG. 14 is a schematic diagram for explaining the operation of the heat absorption and radiation system shown in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Next, an embodiment of the present disclosure will be described with reference to the drawings.

[0011] FIG. 1 is a schematic diagram showing an example of a heat absorption and dissipation system 1 according to the present disclosure. The heat absorption and dissipation system 1 shown in the figure uses a rubidium-manganese-iron cyano complex (Rb x Mn[Fe(CN)6] y(Hereinafter referred to as "RbMnFe complex"). In this embodiment, the liquid heat medium HMf is a mixture of a liquid such as polyalphaolefin oil, which has little change in properties in response to pressure changes, and a powder of RbMnFe complex, which is insoluble in various liquids. The RbMnFe complex is a charge-transfer type phase transition complex having a network structure in which iron and manganese are three-dimensionally cross-linked by cyano groups, and a crystal structure in which rubidium ions are alternately arranged in the voids of the skeleton. The RbMnFe complex exhibits bistability in two states: a high-temperature phase in which the valences of manganese and iron are Mn(II)-Fe(III), and a low-temperature phase in which the valences of manganese and iron are Mn(III)-Fe(II).

[0012] FIG. 2 shows the relationship between the temperature and the magnetic susceptibility of the RbMnFe complex, and FIG. 3 shows the relationship between the temperature of the RbMnFe complex and the amount of heat obtained by a differential scanning calorimeter. As can be seen from these figures, the RbMnFe complex has a first phase transition temperature T LH When heated to above this temperature, the material undergoes a phase transition from a low-temperature phase (see the dashed line in FIG. 2) to a high-temperature phase (see the solid line in FIG. 2) to absorb heat, and the temperature rises to the first phase transition temperature T LH The second phase transition temperature T HL Below this temperature, the RbMnFe complex undergoes a phase transition from the high-temperature phase to the low-temperature phase and releases heat. As shown in Figure 2, the phase transition of the RbMnFe complex also causes temperature hysteresis. As shown in Figure 3, after the RbMnFe complex undergoes a phase transition from the low-temperature phase to the high-temperature phase, it stores the heat absorbed during the phase transition to the high-temperature phase until it transitions back to the low-temperature phase.

[0013] In addition, by changing the ratio of rubidium to manganese in the RbMnFe complex, two phase transition temperatures T LH ,T HL and the phase transition temperature T LH and the phase transition temperature T HL In the RbMnFe complex used in the heat absorption and dissipation system 1 of this embodiment, the ratio x of rubidium to manganese is set to 0.94≦x≦1. This changes the phase transition temperature TLH and the phase transition temperature T HL and the phase transition temperature T LH ,T HL The rate of change of magnetic susceptibility (gradient of change) can be made larger in the vicinity. Note that if the amount of rubidium relative to manganese is reduced, some of the iron cyano atoms are missing and water molecules are coordinated to maintain electrical neutrality.

[0014] Furthermore, as shown in Figures 4A to 4D, when the RbMnFe complex is pressurized, the phase transition temperature T HL and the phase transition temperature T from the low-temperature phase to the high-temperature phase LH Basically, the higher the pressure applied to the RbMnFe complex, the higher the phase transition temperatures T HL ,T LH Therefore, by applying pressure to the RbMnFe complex, the phase transition temperature T LH The phase transition temperature T from the high-temperature phase to the low-temperature phase is lower than HL Therefore, it is possible to dissipate heat by causing a phase transition from the high-temperature phase to the low-temperature phase without significantly lowering the temperature of the RbMnFe complex. Furthermore, according to the experiments and analysis by the present inventors, when the pressure applied to the RbMnFe complex is released, the phase transition temperature T HL and the phase transition temperature T from the low-temperature phase to the high-temperature phase LH It has been confirmed that the temperature of the RbMnFe complex decreases (returns to the original state). Therefore, by reducing the pressure of the pressurized RbMnFe complex, for example to normal pressure, the RbMnFe complex can undergo a phase transition from the low-temperature phase to the high-temperature phase without significantly increasing the temperature of the RbMnFe complex.

[0015] Here, the phase transition temperature T LHis sufficiently low, the RbMnFe complex can undergo phase transition from the low-temperature phase to the high-temperature phase without heating in a room-temperature and normal-pressure environment, and the crystalline state of the RbMnFe complex can be maintained in the high-temperature phase. Furthermore, in this case, the RbMnFe complex can be pressurized in a room-temperature environment to undergo phase transition to the low-temperature phase without cooling, and the RbMnFe complex can be returned to, for example, normal pressure by removing the pressure, thereby undergoing phase transition from the low-temperature phase to the high-temperature phase in a room-temperature environment without heating. For this reason, the present inventors have determined that the phase transition temperature T HL ,T LH As a result of various experiments, the inventors of the present invention found that the phase transition temperature T from the low-temperature phase to the high-temperature phase of the RbMnFe complex in a normal pressure environment can be reduced by doping the Fe in the RbMnFe complex with trivalent cobalt ions, more specifically, with hexacyanocobalt ions. LH It was found that the temperature can be reduced to the room temperature range.

[0016] That is, as shown in FIG. 5, as the amount of cobalt (hexacyanocobalt ion) doped with respect to Fe in the RbMnFe complex increases, the phase transition temperature T HL and the phase transition temperature T from the low-temperature phase to the high-temperature phase LH In addition, as shown in FIG. 5, when the amount of cobalt doped in the RbMnFe complex is 0 to 7%, the phase transition temperature T HL is set to a value in the range of 248K to 307K, and if it is 2 to 7%, the phase transition temperature T HL can be set to a value within a range of 248 K to 290 K. Based on these experimental results, in this embodiment, the liquid heat transfer medium HMf is one containing an RbMnFe complex doped with 2 to 7% cobalt. This makes it possible, under a room temperature and normal pressure environment, to apply pressure to the liquid heat transfer medium HMf to cause a phase transition to a low-temperature phase without cooling the RbMnFe complex, and to release the pressure applied to the liquid heat transfer medium HMf to cause a phase transition to a high-temperature phase without heating the RbMnFe complex.

[0017] The heat absorption / dissipation system 1 using the liquid heat transfer medium HMf containing the RbMnFe complex as described above includes a circulation passage 2, a pump 3 for circulating the liquid heat transfer medium HMf in the circulation passage 2, a valve 4 for opening and closing the circulation passage 2 on the upstream side of the pump 3, a pressurizing device 5 arranged on the downstream side of the pump 3 and the upstream side of the valve 4, and a control device 10. The circulation passage 2 is an endless passage formed by a heat transfer tube 2p and filled with the liquid heat transfer medium HMf, and the outer circumferential surface of the heat transfer tube 2p is covered with a heat insulating material (not shown) except for a part of it. In addition, the circulation passage 2 is provided with a buffer tank 2b communicating with the circulation passage 2 between the pump 3 and the pressurizing device 5, and the buffer tank 2b is fitted with a plug (breather plug) BP for communicating the circulation passage 2, i.e., the inside of the heat transfer tube 2p, with the outside air (atmosphere).

[0018] The pump 3 is, for example, an electric pump, and is controlled by the control device 10 to circulate the liquid heat medium HMf in the circulation passage 2 in a clockwise direction in FIG. 1. The valve 4 is an on-off valve controlled by the control device 10 to open and close the circulation passage 2 on the upstream side of the pump 3 (before the suction port) in the flow direction of the liquid heat medium HMf. When the valve 4 is closed, the inflow of the liquid heat medium HMf to the suction port of the pump 3 is restricted. The pressurizing device 5 pressurizes the liquid heat medium HMf present on the upstream side of the valve 4 in the circulation passage 2, and includes a piston 5p arranged in the heat transfer tube 2p downstream of the buffer tank 2b and upstream of the valve 4 so as to be able to move forward and backward, and a driving device 5d which is a hydraulic actuator or an electric actuator. The driving device 5d of the pressurizing device 5 is controlled by the control device 10 to move the piston 5p so as to compress the liquid heat medium HMf in the heat transfer tube 2p. The control device 10 includes a computer having a CPU, ROM, RAM, input / output interface, etc., various driving circuits, various logic ICs, etc.

[0019] Furthermore, the heat absorption and dissipation system 1 includes a first heat sink 6 and a second heat sink 7 that can exchange heat between the heat transfer tube 2p forming the circulation passage 2 and the outside air, respectively. The first heat sink 6 abuts (closely contacts) with a portion of the heat transfer tube 2p forming the circulation passage 2 between the pump 3 and the pressurizing device 5 from which the insulating material has been removed. The second heat sink 7 can abut (closely contacts) with a portion of the heat transfer tube 2p forming the circulation passage 2 between the pressurizing device 5 and the valve 4 from which the insulating material has been removed. In this embodiment, the second heat sink 7 is connected to a drive device 7d controlled by the control device 10, and the drive device 7d can move the second heat sink 7 away from the corresponding heat transfer tube 2p and bring it into abutment with the heat transfer tube 2p.

[0020] Next, the operation of the heat absorption and dissipation system 1 configured as above will be described.

[0021] When the heat absorption and dissipation system 1 is stopped, the pump 3 is stopped and the valve 4 is opened. When the heat absorption and dissipation system 1 is stopped, the piston 5p of the pressurizing device 5 is moved to an initial position (see FIG. 1) retracted from the circulation passage 2 by the driving device 5d, and the second heat sink 7 is abutted against the corresponding heat transfer tube 2p by the driving device 7d. Furthermore, the liquid heat medium HMf applied to the heat absorption and dissipation system 1 is a mixture of a polyalphaolefin oil or the like as a liquid and an RbMnFe complex, and the RbMnFe complex (Fe) is doped with cobalt (hexacyanocobalt ion). Therefore, when the heat absorption and dissipation system 1 is stopped in a normal temperature and pressure environment, the crystalline state of the RbMnFe complex contained in the liquid heat medium HMf in the circulation passage 2 is maintained in a high temperature phase. As shown in FIG. 1 below, the high temperature phase is indicated by a fine dot pattern.

[0022] When the heat absorption and dissipation system 1 is instructed to start operating, the control device 10 of the heat absorption and dissipation system 1 closes the valve 4 and controls the drive device 5d of the pressurizing device 5 to cause the piston 5p to close the circulation passage 2, as shown in Fig. 6. At this time, as shown in Fig. 6, a part of the liquid heat medium HMf in the circulation passage 2 is pushed by the piston 5p toward the pump 3 and flows into the buffer tank 2b. Next, the control device 10 controls the drive device 5d of the pressurizing device 5 to cause the piston 5p to pressurize the liquid heat medium HMf present upstream of the valve 4 in the circulation passage 2, as shown in Fig. 7. In this embodiment, a pressure of, for example, about 100 MPa is applied from the piston 5p to the liquid heat medium HMf.

[0023] As a result, between the piston 5p (pressurizing device 5) in the circulation passage 2 and the valve 4 in the closed state, the RbMnFe complex contained in the liquid heat transfer medium HMf undergoes a phase transition from the high-temperature phase to the low-temperature phase at a temperature T HL As the temperature of the liquid heat medium HMf increases, the RbMnFe complex undergoes a phase transition from a high-temperature phase to a low-temperature phase under a normal temperature environment, and releases heat to the second heat sink 7 through the heat transfer tube 2p. As shown in FIG. 7, the low-temperature phase is shown by a rough dot pattern. The control device 10 considers that the phase transition from the high-temperature phase to the low-temperature phase of the RbMnFe complex is completed when, for example, a predetermined time has elapsed since the start of pressurization of the liquid heat medium HMf, and controls the drive device 5d to move the piston 5p to the initial position as shown in FIG. 8 to release the pressurization of the liquid heat medium HMf, and controls the drive device 7d to move the second heat sink 7 away from the corresponding heat transfer tube 2p. In this way, by moving the second heat sink 7 away from the heat transfer tube 2p, it is possible to prevent the heat released (transferred) to the second heat sink 7 from being absorbed through the heat transfer tube 2p by the liquid heat medium HMf present between the pressurizer 5 and the valve 4 in the circulation passage 2.

[0024] After the pressurization by the pressurizing device 5 is released, the control device 10 opens the valve 4. Furthermore, the control device 10 operates the pump 3 for a predetermined time to transfer the liquid heat medium HMf present on the downstream side of the piston 5p (pressurizing device 5) and the upstream side of the valve 4 in the circulation passage 2 to the downstream side of the valve 4 (pump 3 side) and the upstream side of the pressurizing device 5 (piston 5p) as shown in FIG. 9. The liquid heat medium HMf pressurized on the downstream side of the pressurizing device 5 and the upstream side of the valve 4 is transferred by the pump 3 to the downstream side of the valve 4 and the upstream side of the pressurizing device 5, and is communicated with the outside air (atmosphere) via the plug BP and the gap of the pump 3, and the pressure applied to the liquid heat medium HMf is released. As a result, the RbMnFe complex contained in the liquid heat medium HMf on the downstream side of the valve 4 and the upstream side of the pressurizing device 5 rises from the low-temperature phase to the high-temperature phase at a phase transition temperature T LH As the temperature of the liquid heat transfer medium HMf decreases, the liquid heat transfer medium HMf undergoes a phase transition from a low-temperature phase to a high-temperature phase in a normal temperature environment, and absorbs heat from the surrounding air, etc., via the first heat sink 6. Therefore, almost the entire liquid heat transfer medium HMf in the circulation passage 2 becomes in the high-temperature phase (see FIG. 1).

[0025] After stopping the pump 3, the control device 10 controls the drive device 7d so that the second heat sink 7 comes into contact with the corresponding heat transfer tube 2p. Furthermore, the control device 10 considers that the phase transition from the low-temperature phase to the high-temperature phase of the RbMnFe complex is completed, for example, when a predetermined time has elapsed since stopping the pump 3. Then, the control device 10 repeatedly executes closing the valve 4, pressurizing the liquid heat medium HMf by the pressurizing device 5, moving (separating) the second heat sink 7, opening the valve 4, transferring the liquid heat medium HMf by the pump 3, and moving (contacting) the second heat sink 7. As a result, it becomes possible to make the heat absorption and dissipation system 1 function as a heat pump that transfers heat from a low-temperature part to a high-temperature part via the liquid heat medium HMf.

[0026] As described above, the heat absorption and dissipation system 1 pressurizes the liquid heat transfer medium HMf containing the RbMnFe complex, and causes the RbMnFe complex to undergo a phase transition from a high-temperature phase to a low-temperature phase, thereby dissipating heat from the liquid heat transfer medium HMf. That is, when the RbMnFe complex is pressurized, the phase transition temperature T HL and the phase transition temperature T from the low-temperature phase to the high-temperature phase LH Therefore, by pressurizing the liquid heat transfer medium HMf, the phase transition temperature T LH The phase transition temperature T from the high-temperature phase to the low-temperature phase is lower than HL Since the temperature T is increased, the RbMnFe complex can undergo a phase transition from the high-temperature phase to the low-temperature phase, and heat can be released from the liquid heat transfer medium HMf without cooling the liquid heat transfer medium HMf (without significantly lowering the temperature). In addition, as described above, when the pressure of the pressurized RbMnFe complex is reduced to near atmospheric pressure, the phase transition temperature T HL and the phase transition temperature T from the low-temperature phase to the high-temperature phase LH is decreased. Therefore, by returning the pressurized liquid heat medium HMf to normal pressure by opening it to the atmosphere or the like, it is possible to cause a phase transition of the RbMnFe complex from a low-temperature phase to a high-temperature phase without heating the liquid heat medium HMf (without significantly increasing the temperature). Furthermore, by repeatedly applying and releasing pressure to the liquid heat medium HMf, it is possible to transfer heat from a low-temperature portion to a high-temperature portion via the liquid heat medium HMf. As a result, it is possible to realize a heat absorption and dissipation system 1 that functions as a heat pump by efficiently absorbing and releasing heat by effectively utilizing the characteristics (pressure-calorie effect) of the RbMnFe complex. The pressurized liquid heat medium HMf may be decompressed to a pressure higher than atmospheric pressure or to a pressure equal to or lower than atmospheric pressure depending on the required amount of heat absorption.

[0027] In the above embodiment, the Fe in the RbMnFe complex contained in the liquid heat transfer medium HMf is doped with cobalt (hexacyanocobalt ion), so the phase transition temperature T LHThis makes it possible, under a room-temperature and normal pressure environment, to pressurize the liquid heat transfer medium HMf with the pressurizing device 5 to cause a phase transition of the RbMnFe complex to a low-temperature phase without cooling, and to release the pressure of the liquid heat transfer medium HMf to return the RbMnFe complex to normal pressure, thereby causing a phase transition of the RbMnFe complex to a high-temperature phase without heating.

[0028] Furthermore, in the above embodiment, the liquid heat transfer medium HMf is a mixture of a liquid such as polyalphaolefin oil and an RbMnFe complex (powder). That is, the RbMnFe complex is a powder that is insoluble in various liquids, and even if it is enclosed in a liquid, its heat absorption and heat release performance is maintained. Furthermore, by enclosing the RbMnFe complex (powder) in a liquid, it is possible to apply pressure (liquid pressure) uniformly to each powder. Therefore, the heat absorption and release system 1 using the liquid heat transfer medium HMf containing the RbMnFe complex can realize stable heat absorption and release while simplifying the configuration compared to a heat pump that utilizes gas-liquid phase transition.

[0029] The heat absorption and release system 1 also includes a circulation passage 2, a pump 3 for circulating the liquid heat transfer medium HMf through the circulation passage 2, a valve 4 for opening and closing the circulation passage 2 on the upstream side of the pump 3, and a pressurizing device 5 for pressurizing the liquid heat transfer medium HMf present on the upstream side of the valve 4 in the circulation passage 2 on the downstream side of the pump 3. With this, when the pump 3 is stopped and the valve 4 is closed, the pressurizing device 5 pressurizes the liquid heat transfer medium HMf present on the upstream side of the valve 4 in the circulation passage 2, thereby causing a phase transition from a high-temperature phase to a low-temperature phase in the RbMnFe complex contained in the liquid heat transfer medium HMf present between the pressurizing device 5 and the valve 4 in the circulation passage 2, thereby dissipating heat. Furthermore, after the pressurization by the pressurizing device 5 is released, the valve 4 is opened and the liquid heat transfer medium HMf present in the circulation passage 2 downstream of the pressurizing device 5 and upstream of the valve 4 is transported by the pump 3 to the downstream of the valve 4 and upstream of the pressurizing device 5, whereby the pressure applied to the liquid heat transfer medium HMf downstream of the pressurizing device 5 and upstream of the valve 4 is released downstream of the valve 4 and upstream of the pressurizing device 5, causing the RbMnFe complex to undergo a phase transition from a low-temperature phase to a high-temperature phase and absorb heat. As a result, by repeatedly performing the closing of the valve 4, the pressurization of the liquid heat transfer medium HMf by the pressurizing device 5, the opening of the valve 4, and the transport of the liquid heat transfer medium HMf by the pump 3, the heat absorption and release system 1 can function as a heat pump that transfers heat from a low-temperature part to a high-temperature part via the liquid heat transfer medium HMf.

[0030] 10, a second valve 8 for opening and closing the circulation passage 2 may be provided downstream of the pump 3 and upstream of the pressurizing device 5 in the vicinity of the pressurizing device 5. This makes it possible to prevent the liquid heat medium HMf pressurized by the pressurizing device 5 from flowing into the pump 3 by closing the second valve 8 when the pressurizing device 5 pressurizes the liquid heat medium HMf upstream of the valve 4. As a result, in the heat absorption and release system 1B, as shown in the figure, the buffer tank 2b can be omitted or the volume of the buffer tank 2b can be made smaller.

[0031] In addition, there is a certain difference between the pressure required to start the phase transition of the RbMnFe complex contained in the liquid heat transfer medium HMf from the high-temperature phase to the low-temperature phase under normal temperature conditions and the pressure required to complete the phase transition of the RbMnFe complex from the high-temperature phase to the low-temperature phase under normal temperature conditions. Furthermore, once the phase transition of the RbMnFe complex from the high-temperature phase to the low-temperature phase is started, a heat absorption / dissipation cycle can be formed even if the pressure applied to the RbMnFe complex is released before the phase transition is completed. Therefore, the pressure applied to the liquid heat transfer medium HMf from the pressurizing device 5 may be changed according to the amount of heat (temperature gradient) required for the heat absorption / dissipation system 1, 1B. This makes it possible to suppress unnecessary pressurization of the liquid heat transfer medium HMf and further improve the energy efficiency of the heat absorption / dissipation system 1, 1B.

[0032] By the way, by doping the Fe in the RbMnFe complex with trivalent cobalt ions (hexacyanocobalt ions), the phase transition temperature T LH However, the inventors' research has revealed that doping the Mn (manganese) of the RbMnFe complex with a divalent metal ion can lower the phase transition temperature from the low-temperature phase to the high-temperature phase of the RbMnFe complex in a normal pressure environment to the room temperature range, or conversely, raise it. That is, as shown in FIG. 11, doping the Mn (manganese) of the RbMnFe complex with a divalent copper (Cu) ion, divalent nickel (Ni) ion, or divalent zinc (Zn) ion can lower the phase transition temperature T LH can be lowered to room temperature range.

[0033] More specifically, the doping amount of divalent copper (Cu) ions relative to Mn in the RbMnFe complex is set to, for example, 6 to 8%, or the doping amount of divalent nickel (Ni) ions or divalent zinc (Zn) ions is set to, for example, 2 to 8%, so that the phase transition temperature T HLcan be set to a value within a range of 250K to 290K. Therefore, even if copper, nickel, or zinc is used as a dopant for the RbMnFe complex, it is possible to apply pressure to the liquid heat transfer medium HMf in a room temperature and pressure environment to cause a phase transition to a low-temperature phase without cooling the RbMnFe complex, and to release the pressure applied to the liquid heat transfer medium HMf to cause a phase transition to a high-temperature phase without heating the RbMnFe complex. Furthermore, as shown in FIG. 11, even if the Mn in the RbMnFe complex is doped with divalent iron (Fe) ions, the phase transition temperature T LH can be reduced.

[0034] On the other hand, when the Mn (manganese) of the RbMnFe complex is doped with divalent cobalt (Co) ions, the phase transition temperature T LH This makes it possible to realize a heat absorption / dissipation system that operates in high-temperature environments by using divalent cobalt ions as a dopant for the RbMnFe complex.

[0035] Furthermore, as shown in FIG. 12, when zinc is used as a dopant for the RbMnFe complex, the phase transition temperature T LH and the phase transition temperature T HL By setting the doping amount to 4-8%, it is possible to reduce the difference (hysteresis width) between the phase transition temperature T LH and the phase transition temperature T HL This can reduce the difference (hysteresis width) between the phase transition temperature T LH and the phase transition temperature T HL Therefore, an increase in the difference (hysteresis width) between the measured value and the actual value can be effectively suppressed.

[0036] Fig. 13 is a schematic diagram showing another heat absorption and dissipation system 1C of the present disclosure. The heat absorption and dissipation system 1C shown in the figure uses a solid heat medium HMs obtained by solidifying a RbMnFe complex (powder) doped with cobalt (hexacyanocobalt) into a substantially rectangular parallelepiped or cubic shape using a binder or the like, instead of the liquid heat medium HMf as described above. Furthermore, the heat absorption and dissipation system 1C includes a heat insulating container 20 that contains (holds) the solid heat medium HMs, a pressurizing device 50 that pressurizes the solid heat medium HMs, a heat sink 70, and a control device (not shown).

[0037] The heat-insulating container 20 includes an opening / closing door 21 that opens and closes an opening 20o formed in a side wall of the heat-insulating container 20 so as to approach the solid heat medium HMs placed inside the heat-insulating container 20. The opening / closing door 21 is opened and closed by an opening / closing mechanism (not shown) controlled by a control device of the heat absorption / dissipation system 1C. By opening the opening / closing door 21, it becomes possible to bring the solid heat medium HMs into contact with outside air. The pressurizing device 50 includes a piston 51 that can move toward and away from a pressure-receiving surface (upper surface in FIG. 13) of the solid heat medium HMs placed inside the heat-insulating container 20, and a driving device (not shown). The driving device is controlled by a control device of the heat absorption / dissipation system 1C to move the piston 51 relative to the solid heat medium HMs so as to apply pressure to the pressure-receiving surface, and can move the piston 51 away from the solid heat medium HMs. The heat sink 70 is movably supported by the insulated container 20 so that a part of it (the lower surface in FIG. 13) always protrudes (exposed) to the outside from the insulated container 20, and can abut (come into close contact with) a heat transfer surface (the lower surface in FIG. 13) located opposite the pressure-receiving surface of the solid heat medium HMs. The heat sink 70 is connected to a heat sink drive device (not shown) controlled by the control device 10, and the heat sink drive device can move the heat sink 70 away from the solid heat medium HMs and bring it into contact with the heat transfer surface of the solid heat medium HMs.

[0038] When the operation of the heat absorption and dissipation system 1C configured as described above is stopped, the crystalline state of the RbMnFe complex contained in the solid heat medium HMs is maintained in the high-temperature phase, and the opening and closing door 21 of the heat-insulating container 20 is closed. When an instruction to start the operation of the heat absorption and dissipation system 1C is given, the control device of the heat absorption and dissipation system 1 controls the heat sink drive device so that the heat sink 70 abuts against the heat transfer surface of the solid heat medium HMs, as shown in FIG. 14. Furthermore, the control device controls the drive device of the pressure device 50 so that the piston 51 moves relative to the solid heat medium HMs to apply pressure (for example, about 100 MPa) to the pressure-receiving surface of the solid heat medium HMs. As a result, the RbMnFe complex contained in the solid heat medium HMs undergoes a phase transition temperature T HL As the temperature of the material increases, the material undergoes a phase transition from a high-temperature phase to a low-temperature phase in a normal temperature environment, and releases heat to the heat sink 70.

[0039] The control device 10 of the heat absorption and dissipation system 1C considers that the phase transition from the high-temperature phase to the low-temperature phase of the RbMnFe complex is completed, for example, when a predetermined time has elapsed since the start of pressurization of the solid heat medium HMs, and controls the drive device 5d of the pressurization device 50 to move the piston 51 to the initial position and release the pressurization of the solid heat medium HMs, as shown in Fig. 13. Furthermore, the control device controls the heat sink drive device to move the heat sink 70 away from the solid heat medium HMs (see Fig. 13). This makes it possible to prevent the heat released (transmitted) to the heat sink 70 from being absorbed by the solid heat medium HMs.

[0040] After the pressurization by the pressurizing device 50 is released, the control device of the heat absorption and dissipation system 1C controls the opening and closing mechanism to open the opening and closing door 21 as shown by the dashed line in Fig. 13. As a result, the solid heat medium HMs is heated to a phase transition temperature T LHAs the temperature of the solid heat medium HMs decreases, the solid heat medium HMs undergoes a phase transition from a low-temperature phase to a high-temperature phase under normal temperature conditions, and absorbs heat from the air flowing in through the opening 20o of the heat-insulating container 20. As a result, the solid heat medium HMs in the heat-insulating container 20 becomes almost entirely in the high-temperature phase. The control device of the heat absorption and dissipation system 1C determines that the phase transition from the low-temperature phase to the high-temperature phase of the RbMnFe complex is completed, for example, when a predetermined time has elapsed since the opening and closing door 21 was opened, and controls the opening and closing mechanism to close the opening and closing door 21. Thereafter, the control device of the heat absorption and dissipation system 1C repeatedly executes the movement (contact) of the heat sink 70, the pressurization of the solid heat medium HMs by the pressurizing device 50, the movement (separation) of the heat sink 70, and the opening and closing of the opening and closing door 21. As a result, the heat absorption and dissipation system 1C can function as a heat pump that transfers heat from a low-temperature part to a high-temperature part via the liquid heat medium HMf.

[0041] Also, in the heat absorption and dissipation system 1C, there is a certain difference between the pressure required to start the phase transition of the RbMnFe complex contained in the solid heat medium HMs from the high-temperature phase to the low-temperature phase under normal temperature conditions and the pressure required to complete the phase transition of the RbMnFe complex from the high-temperature phase to the low-temperature phase under normal temperature conditions. Furthermore, once the phase transition of the RbMnFe complex from the high-temperature phase to the low-temperature phase is started, the pressure applied to the RbMnFe complex before the phase transition is completed can be released to form a heat absorption and dissipation cycle. Therefore, the pressure applied to the solid heat medium HMs from the pressurizing device 50 may be changed according to the amount of heat (temperature gradient) required for the heat absorption and dissipation system 1C. This makes it possible to suppress the solid heat medium HMs from being pressurized unnecessarily, and to further improve the energy efficiency and durability of the solid heat medium HMs in the heat absorption and dissipation system 1C. In addition, in the heat absorption and dissipation system 1C, the strength of the solid heat medium HMs can be easily ensured, so that the need to consider the pressure resistance of the solid heat medium HMs and the like can be reduced.

[0042] As described above, the heat absorption system of the present disclosure is a heat absorption and release system (1, 1B, 1C) that uses a heat medium (HMf, HMs) containing a rubidium-manganese-iron cyano complex, and applies pressure to the heat medium (HMf, HMs) to cause a phase transition of the rubidium-manganese-iron cyano complex from a high temperature phase to a low temperature phase, thereby releasing heat from the heat medium (HMf, HMs), and releases the pressure applied to the heat medium (HMf, HMs) to cause a phase transition of the rubidium-manganese-iron cyano complex from a low temperature phase to a high temperature phase, thereby causing the heat medium (HMf, HMs) to absorb heat, and repeatedly applies and releases pressure to the heat medium (HMf, HMs).

[0043] The heat absorption and dissipation system of the present disclosure applies pressure to a heat medium containing a rubidium-manganese-iron cyano complex, and causes the rubidium-manganese-iron cyano complex to undergo a phase transition from a high-temperature phase to a low-temperature phase, thereby releasing heat from the heat medium. That is, when pressure is applied to the rubidium-manganese-iron cyano complex, the phase transition temperature from the high-temperature phase to the low-temperature phase and the phase transition temperature from the low-temperature phase to the high-temperature phase increase. Therefore, by applying pressure to the heat medium, the phase transition temperature from the high-temperature phase to the low-temperature phase, which is lower than the phase transition temperature from the low-temperature phase to the high-temperature phase, increases, so that the rubidium-manganese-iron cyano complex can undergo a phase transition from the high-temperature phase to the low-temperature phase, thereby releasing heat from the heat medium, without significantly lowering the temperature of the heat medium. In addition, the present inventors have confirmed that when the pressure applied to the rubidium-manganese-iron cyano complex is released, the phase transition temperature from the high-temperature phase to the low-temperature phase and the phase transition temperature from the low-temperature phase to the high-temperature phase decrease. Therefore, by releasing the pressure applied to the heat medium, it is possible to cause the rubidium-manganese-iron cyano complex to undergo a phase transition from a low-temperature phase to a high-temperature phase without significantly increasing the temperature of the heat medium. Furthermore, by repeatedly applying and releasing pressure to the heat medium, heat can be transferred from a low-temperature portion to a high-temperature portion via the heat medium. As a result, it is possible to realize a heat absorption and release system that effectively utilizes the properties of the rubidium-manganese-iron cyano complex to efficiently absorb and release heat and function as a heat pump.

[0044] Furthermore, the iron of the rubidium-manganese-iron cyano complex may be doped with cobalt.

[0045] This allows the phase transition temperature of the rubidium-manganese-iron cyano complex from the low-temperature phase to the high-temperature phase in an ordinary pressure environment to be lowered to the ordinary temperature range, and as a result, in an ordinary temperature and ordinary pressure environment, it is possible to pressurize the heat medium to cause the rubidium-manganese-iron cyano complex to undergo phase transition to the low-temperature phase without cooling, and to release the pressurization of the heat medium to return the rubidium-manganese-iron cyano complex to ordinary pressure, thereby causing the rubidium-manganese-iron cyano complex to undergo phase transition to the high-temperature phase without heating.

[0046] Furthermore, the manganese in the rubidium-manganese-iron cyano complex may be doped with a divalent metal ion.

[0047] This makes it possible to lower the phase transition temperature from the low-temperature phase to the high-temperature phase of the rubidium-manganese-iron cyano complex in an ambient pressure environment to the room temperature range, or conversely, to raise it.

[0048] The heat transfer medium may be a liquid heat transfer medium (HMf) in which the rubidium-manganese-iron cyano complex is mixed in a liquid.

[0049] That is, the rubidium-manganese-iron cyano complex is a powder that is insoluble in various liquids, and even when it is enclosed in a liquid, its heat absorption and heat release performance is maintained, and by enclosing the powder in a liquid, pressure (liquid pressure) can be applied uniformly to each powder. Therefore, in a heat absorption and release system using a liquid heat transfer medium containing a rubidium-manganese-iron cyano complex, it is possible to realize stable heat absorption and release while simplifying the configuration compared to a heat pump that uses a gas-liquid phase transition.

[0050] Furthermore, the heat absorption and release system (1, 1B) may include a circulation passage (2), a pump (3) that circulates the liquid heat transfer medium (HMf) in the circulation passage (2), a valve (4) that opens and closes the circulation passage (2) upstream of the pump (3), and a pressurizing device (5) that pressurizes the liquid heat transfer medium (HMf) present in the circulation passage (2) upstream of the valve (4) downstream of the pump (3).

[0051] This makes it possible for the heat absorption and dissipation system to function as a heat pump that transfers heat from a low-temperature area to a high-temperature area via the liquid heat medium by repeatedly closing the valve, pressurizing the liquid heat medium with a pressurizing device, opening the valve, and transferring the liquid heat medium with a pump.

[0052] The heat absorption / dissipation system (1B) may further include a second valve (8) for opening and closing the circulation passage (2) downstream of the pump (3) and upstream of the pressurizing device (5).

[0053] As a result, by closing the second valve when the pressurizing device pressurizes the liquid heat transfer medium upstream of the valve, it is possible to prevent the liquid heat transfer medium pressurized by the pressurizing device from flowing into the pump side.

[0054] The present disclosure is not limited to the above embodiment, and various modifications can be made within the scope of the present disclosure. Furthermore, the above embodiment is merely a specific form of the invention described in the Summary of the Invention, and does not limit the elements of the invention described in the Summary of the Invention. [Industrial Applicability]

[0055] The present disclosure is applicable to the heat absorption and dissipation system manufacturing industry and the like.

Claims

1. A heat absorption and release system using a liquid heat transfer medium in which a rubidium-manganese-iron cyano complex is mixed into the liquid, A circulation path, a pump that circulates the liquid heat transfer medium through the circulation passage; a valve that opens and closes the circulation passage upstream of the pump; a pressurizing device that pressurizes the liquid heat transfer medium present in the circulation passage downstream of the pump and upstream of the valve, The valve is closed and pressure is applied to the liquid heat medium by the pressurizing device, causing the rubidium-manganese-iron cyano complex to undergo a phase transition from a high-temperature phase to a low-temperature phase and releasing heat from the liquid heat medium, and the valve is opened and the pump is operated to release the pressure applied to the liquid heat medium, causing the rubidium-manganese-iron cyano complex to undergo a phase transition from a low-temperature phase to a high-temperature phase and allowing the liquid heat medium to absorb heat, and the application of pressure to the liquid heat medium that has absorbed heat and the release of the pressure applied to the liquid heat medium are repeatedly performed to transfer heat from a low-temperature portion to a high-temperature portion via the liquid heat medium. This heat absorption and release system functions as a heat pump.

2. The heat absorption and dissipation system according to claim 1, A heat absorption / dissipation system in which the iron of the rubidium-manganese-iron cyano complex is doped with cobalt.

3. The heat absorption and dissipation system according to claim 1, A heat absorption / dissipation system in which the manganese in the rubidium-manganese-iron cyano complex is doped with a divalent metal ion.

4. The heat absorption and dissipation system according to any one of claims 1 to 3, The heat absorption / dissipation system further includes a second valve downstream of the pump and upstream of the pressurizing device for opening and closing the circulation passage.

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