Refrigeration device with heat regeneration using flowable electrocaloric refrigeration material

Abstract

A refrigeration device using a flowable electrocaloric refrigeration material and having a heat regeneration function comprises a flow channel used for circulating flowing of the flowable electrocaloric refrigeration material, heat exchange mechanisms arranged on the two sides of the flow channel, a fluid driving mechanism arranged in the flow channel and the flowable electrocaloric refrigeration material, and the fluid driving mechanism drives fluid to circularly flow in the flow channel. The flowable electrocaloric refrigeration material releases heat when flowing into the high-field-intensity electric field area from the non-electric-field area, absorbs heat when flowing into the non-electric-field area from the high-field-intensity electric field area, absorbs heat when flowing into the high-field-intensity electric field area from the non-electric-field area, and releases heat when flowing into the non-electric-field area from the high-field-intensity electric field area. Liquid and flowable electrocaloric refrigeration materials are used as refrigeration working media, refrigeration-heating circulation is formed by heat absorption and release of the electrocaloric effect of fluid materials and fluid circulation flow, the external contact thermal resistance of the working media and a heat regenerator, a heat exchanger and the like in the circulation process can be effectively reduced, and the thermodynamic efficiency of the system is improved.

Description

Technical Field

[0001] This invention relates to a technology in the field of electronic card materials, specifically a refrigeration device with heat recovery that uses a mobile electronic card refrigeration material. Background Technology

[0002] Electrocaloric materials are materials exhibiting the electrocaloric effect. The electrocaloric effect is the characteristic of insulating dielectric materials where the entropy changes with the external electric field. When the applied external electric field strength changes, the polarization intensity within the material changes, leading to a change in entropy, which macroscopically manifests as the absorption and release of heat. Heat transfer requires a temperature difference, which exists within the electrocaloric material, between the electrocaloric material and the heat sink, and between the electrocaloric material and the cooling element. To increase energy efficiency, the temperature difference between the electrocaloric material and the heat sink / cooling element should be minimized.

[0003] In a cycle process that does not employ regeneration, such as Figure 1 As shown, when the electric field changes, heat is generated from the material. Part of this heat is transferred to the heat sink via heat exchange, and then to the heat exchanger. The remaining heat remains within the material, is carried to an electric field of higher intensity, and is absorbed by the material. The material then generates cold energy, which is transferred to the heat exchanger via heat exchange and collected. In this heat cycle, only a portion of the heat and cold energy is conducted out, while the rest is consumed within the material itself. Summary of the Invention

[0004] This invention addresses the problems of low thermal conductivity, high friction coefficient, high interfacial thermal resistance, and poor heat recovery effect of solid electrocaloric materials used in existing electrocaloric refrigeration systems. It proposes a heat recovery refrigeration device using a flowable electrocaloric refrigeration material. This device uses a liquid, flowable electrocaloric material as the refrigerant, utilizing the electrocaloric effect of the fluid material to absorb and release heat, forming a refrigeration-heating cycle with fluid circulation. This effectively reduces the contact thermal resistance between the refrigerant and external components such as the regenerator and heat exchanger during the circulation process, thereby improving the system's thermodynamic efficiency.

[0005] This invention is achieved through the following technical solution:

[0006] This invention relates to a regenerative refrigeration device using a mobile electrocaloric refrigeration material, comprising: a flow channel for the circulation of the mobile electrocaloric refrigeration material, heat exchange mechanisms disposed on both sides of the flow channel, a fluid driving mechanism disposed within the flow channel, and the mobile electrocaloric material, wherein: the fluid driving mechanism drives the fluid to circulate within the flow channel, the mobile electrocaloric material releases heat when flowing from a region without an electric field to a region with a high electric field strength, absorbs heat when flowing from a region with a high electric field strength to a region without an electric field, absorbs heat when flowing from a region without an electric field to a region with a high electric field strength, and releases heat when flowing from a region with a high electric field strength to a region without an electric field.

[0007] The flow channel is achieved through a solid channel and a regenerating baffle plate disposed within the solid channel; the flowable electrocooling material is disposed within the solid channel.

[0008] The aforementioned heat recovery baffle divides the solid channel into a U-shaped or S-shaped structure.

[0009] The electric field-free region and the high electric field region are matched with the shape of the U-shaped or S-shaped structure.

[0010] The electric field is generated by applying a voltage to the upper and lower surfaces of the solid channel.

[0011] The fluid drive mechanism is implemented using, but is not limited to, a pump, preferably an ultrasonic drive pump, an electrostatic drive pump, a magnetic stirring pump, a centrifugal jet pump, or a solid motion drive pump.

[0012] The fluidized card cooling material mentioned herein is, but is not limited to, insulating fluids such as 4-cyano-4'-carbon branched biphenyl, chloroform, trichloromethane, polychlorinated biphenyls, siloxane oil, high molecular weight hydrocarbons, and alkanes with more than five carbon atoms.

[0013] The carbon branches in the 4-cyano-4'-carbon-branched biphenyl include, but are not limited to, ethyl, propyl, butyl, n-pentyl, and hexyl.

[0014] The polymer-stabilized liquid crystal is formed by mixing high molecular weight hydrocarbons with dielectric polymers such as polyvinylidene fluoride, trifluoroethylene, and chlorofluoroethylene, wherein the polymer accounts for 5%-20% of the monomers.

[0015] The viscosity of the described flowable calorific cooling material varies with temperature, and its viscosity range is 0.1-20 Pas.

[0016] The thermal conductivity of the regenerating baffle of the solid flow channel is 0.01-2000 W / mK along the fluid flow direction and 0.02-2000 W / mK perpendicular to the fluid flow direction.

[0017] The heat exchange mechanism includes two heat exchangers for cold storage and heat storage, which respectively transfer and store cold or heat through solid channels to the cooling side and heating side of the mobile electrolytic refrigeration material.

[0018] Technical effect

[0019] Compared with the prior art, the present invention uses a mobile electrocaloric refrigeration material as the refrigerant and enables the refrigeration device to work by regulating the electric field. The present invention has a high degree of overall device integration and a smaller size. At the same time, the refrigeration device is expected to have a COP of over 10 at 8K and a thermodynamic perfection of over 25%, which is energy-saving and environmentally friendly. Attached Figure Description

[0020] Figure 1 A schematic diagram showing the flow of heat and cold in a refrigeration cycle using an electrocaloric material that does not employ heat recovery;

[0021] Figure 2 This is a schematic diagram of the invention;

[0022] Figure 3 This is a schematic diagram showing the positions of each component in the refrigeration system of Example 1;

[0023] Figure 4 This is a schematic diagram showing the positions of each component in the refrigeration system of Example 2;

[0024] Figure 5 Temperature distribution diagram of mobile calorie cooling material at different locations;

[0025] In the diagram: 1. Flowable electric refrigerant, 2. Solid channel, 3. Heat exchanger, 4. Regenerative baffle, 5. Heat exchanger, 6. Pump; The area indicated by the dashed line is the high electric field region, and the blank area is the region without electric field.

[0026] Figure 6 This is a schematic diagram illustrating the effect of an example. Detailed Implementation

[0027] Example 1

[0028] like Figure 3 As shown, this embodiment includes: a solid channel 2 for the circulation of a mobile electro-caloric cooling material, heat exchange mechanisms 3 and 5 disposed on both sides of the channel, a pump 6 disposed within the channel, and a mobile electro-caloric cooling material 1. The pump 6 drives the fluid to circulate within the channel. The mobile electro-caloric cooling material 1 releases heat when flowing from a region without an electric field into a region with a high electric field strength, absorbs heat when flowing from a region with a high electric field strength into a region without an electric field, absorbs heat again when flowing from a region without an electric field into a region with a high electric field strength, and releases heat when flowing from a region with a high electric field strength into a region without an electric field.

[0029] The solid channel 2 achieves a U-shaped structure through a built-in regenerative baffle 4. The flowable electric cooling material 1 passes through the interface—the interface between the high-field and no-field regions—which is also the center surface of the regenerative baffle in the solid channel. The electric field strength at this interface changes, leading to a change in entropy. Heat exchangers responsible for cold and heat storage are placed on both sides of the solid channel.

[0030] Example 2

[0031] like Figure 4 As shown, in this embodiment, the solid channel 2 is obstructed by the built-in regenerative baffle 4 in a serpentine structure. The arrows in the schematic diagram represent the flow direction of the flowable electrocaloric refrigerant. Furthermore, the inlet at the bottom of the solid channel is connected to the outlet at the top, allowing the flowable electrocaloric refrigerant to flow downwards. As the fluid flows across the interface, the electric field strength changes, resulting in a change in entropy. Heat exchangers responsible for cold and heat storage are placed on both sides of the solid channel.

[0032] In Examples 1 and 2, when the movable refrigeration material 1 flows through the heating side, the heat it generates is conducted to the heat exchanger and stored. When the movable refrigeration material 1 flows through the cooling side, the cold energy it generates is conducted to the heat exchanger and stored. If the cooling side is placed in a high-temperature environment or in contact with a high-temperature object, the heat from the environment or object will be carried away by the refrigeration element, and the temperature will decrease.

[0033] On both sides of the regenerating baffle in the solid flow channel, the fluid flows in opposite directions. From the heating side to the cooling side, the temperature distribution of the flowable electrostatic refrigerant 1 on both sides of the regenerating baffle 4 is as follows: Figure 5 As shown. A temperature difference exists on both sides of the same location on the regenerative baffle. This temperature difference allows heat to transfer from the side with the higher temperature to the side with the lower temperature, achieving the regenerative effect. Initially, the temperature of all components within the device remains consistent with room temperature. When the fluid just begins to flow, the temperature T of the heat exchanger responsible for heat storage in the refrigeration system is... H and the temperature T of the heat exchanger responsible for cold storage in the refrigeration system. L Change begins. When the cycle reaches a steady state, T... L and T H They will all tend to stabilize. By changing the maximum electric field strength E applied in the refrigeration system... H (E h The output work of the pump, or the fluid velocity, can enable the refrigeration system to achieve a maximum temperature difference ΔT = T. H -T L The expected results were achieved.

[0034] Numerical simulation analysis showed that a device using 4'-n-pentyl-4-cyanobiphenyl as the mobile electrostatic refrigeration material 1, with a regenerative partition length of 10 cm and a solid channel width of 0.5 cm, can generate a stable temperature difference of approximately 16°C at both the hot and cold ends. Its working effect is as follows: Figure 6 As shown.

[0035] In summary, this device does not use gas-liquid phase change, but achieves the cooling effect through liquid-liquid phase change; it does not use a compressor, but only a pump to drive the liquid flow, resulting in small size and low noise; it uses a mobile electrocaloric refrigeration material, which is simpler to design, easier to implement, has higher utilization rate, and less loss compared to solid electrocaloric refrigeration devices.

[0036] The above-described specific implementations can be partially adjusted by those skilled in the art in different ways without departing from the principles and purpose of the present invention. The scope of protection of the present invention is defined by the claims and is not limited to the above-described specific implementations. All implementation schemes within the scope of the claims are bound by the present invention.

Claims

1. A regenerative refrigeration device using a mobile calorific value refrigeration material, characterized in that, include: The flow channel for circulating the mobile electro-caloric refrigeration material, the heat exchange mechanism disposed on both sides of the flow channel, the fluid drive mechanism disposed within the flow channel, and the mobile electro-caloric refrigeration material, wherein: the fluid drive mechanism drives the fluid to circulate within the flow channel; the mobile electro-caloric refrigeration material releases heat when flowing from a region without an electric field to a region with a high electric field strength, absorbs heat when flowing from a region with a high electric field strength to a region without an electric field, absorbs heat when flowing from a region without an electric field to a region with a high electric field strength, and releases heat when flowing from a region with a high electric field strength to a region without an electric field; The heat exchange mechanism includes two heat exchangers for cold storage and heat storage, which respectively transfer and store cold or heat through solid channels to the cooling side and heating side of the mobile electrolytic refrigeration material.

2. The regenerative refrigeration device using a mobile calorific value refrigeration material according to claim 1, characterized in that, The flow channel is realized through a solid channel and a heat recovery baffle disposed within the solid channel; the fluid electrocard material is disposed within the solid channel.

3. The regenerative refrigeration device using a mobile calorific value refrigeration material according to claim 1 or 2, characterized in that, The aforementioned heat recovery baffle divides the solid channel into a U-shaped or S-shaped structure; The thermal conductivity of the regenerating baffle along the fluid flow direction is 0.01-2000 W / mK, and the thermal conductivity perpendicular to the fluid flow direction is 0.02-2000 W / mK.

4. The regenerative refrigeration device using a mobile calorific value refrigeration material according to claim 1, characterized in that, The electric field-free region and the high electric field region are matched with the shape of the U-shaped or S-shaped structure.

5. The regenerative refrigeration device using a mobile calorific value refrigeration material according to claim 1, characterized in that, The fluid drive mechanism is an ultrasonic drive pump, an electrostatic drive pump, a magnetic stirring pump, a centrifugal jet pump, or a solid motion drive pump.

6. The regenerative refrigeration device using a mobile calorific value refrigeration material according to claim 1, characterized in that, The aforementioned mobile refrigeration material uses 4-cyano-4'-carbon branched biphenyl, chloroform, trichloromethane, polychlorinated biphenyl, siloxane oil, high molecular weight hydrocarbons, or alkanes with more than five carbon atoms. The viscosity of the described flowable calorific cooling material varies with temperature, and its viscosity range is 0.1-20 Pas.

7. The regenerative refrigeration device using a mobile calorific value refrigeration material according to claim 6, characterized in that, The polymer-stabilized liquid crystal is formed by mixing high molecular weight hydrocarbons with dielectric polymers such as polyvinylidene fluoride, trifluoroethylene, and chlorofluoroethylene, wherein the polymer accounts for 5%-20% of the monomers.

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