HEAT-RELEASE RETARDATIVE COLD CONDUCTION DEVICE WITH MULTI-CAVITY AND MULTI-PHASE CHANGE AND METHOD OF CALCULATING TRANSFER HEAT THEREOF

Abstract

The invention provides a heat-release retardative cold conduction device with multi-cavity and multi-phase change and a method of calculating the transfer heat thereof. The device comprises an inner cavity, a heat-release retardative cavity, and a phase-change cold storage cavity. The inner cavity is a hollow sealing structure with an unobstructed central core and two closed ends, and a refrigerant is placed in the cavity; the heat-release retardative cavity is encased on a bottom region outside of the inner cavity, and a phase-change heat storage material is placed in the heat-release retardative cavity; the phase-change cold storage cavity is encased on the outside of the inner cavity and is located in a region above the heat-release retardative cavity, wherein the phase-change cold storage cavity does not completely encase a top region outside of the inner cavity, and a phase-change cold storage material is placed in the phase-change cold storage cavity.

Claims

1. A heat-release retardative cold conduction device with multi-cavity and multi-phase change, which is applicable to permafrost engineering and comprises: an inner cavity, wherein the inner cavity is a hollow sealing structure with an unobstructed central core and two closed ends, and a refrigerant is placed in the cavity; a heat-release retardative cavity encasing a bottom region outside of the inner cavity, wherein a phase-change heat storage material is placed in the heat-release retardative cavity, the phase-change heat storage material undergoes phase transition at low temperatures to regulate spatiotemporal distributions of heat; a phase-change cold storage cavity encasing the outside of the inner cavity and located in a region above the heat-release retardative cavity, wherein the phase-change cold storage cavity does not completely encase a top region outside of the inner cavity, and a phase-change cold storage material is placed in the phase-change cold storage cavity, when an outer wall temperature of the phase-change cold storage cavity reduces to a phase change temperature of the phase-change cold storage material, the phase-change cold storage material undergoes phase transition to store cold energy, thereby reducing the outer wall temperature of the phase-change cold storage cavity; and a heat dissipation cavity encasing the outside of the inner cavity and located in a region above the phase-change cold storage cavity, wherein a unidirectional heat conductive material is placed in the heat dissipation cavity; wherein, the heat-release retardative cavity and a corresponding portion of the inner cavity encased by the heat-release retardative cavity constitute a heat-release retardative evaporation section, the phase-change cold storage cavity and a corresponding portion of the inner cavity encased by the phase-change cold storage cavity constitute an intensive condensation section, and the heat dissipation cavity and a corresponding portion of the inner cavity encased by the heat dissipation cavity constitute a condensation section, a double temperature difference is formed between the heat-release retardative evaporation section and the intensive condensation section, as well as between the heat-release retardative evaporation section and the condensation section, this ensures a balanced and continuous distribution of cooling in both space and time, thereby improving actual efficiency of cold conduction and working time.

2. The heat-release retardative cold conduction device with multi-cavity and multi-phase change according to claim 1, further comprises: a heat insulation cavity encasing the outside of the inner cavity and located in a region above the heat-release retardative cavity and in a region below the phase-change cold storage cavity, wherein a heat insulation material is placed in the heat insulation cavity.

3. The heat-release retardative cold conduction device with multi-cavity and multi-phase change according to claim 2, wherein the heat insulation cavity and a corresponding portion of the inner cavity encased by the heat insulation cavity constitute a heat insulation section.

4. The heat-release retardative cold conduction device with multi-cavity and multi-phase change according to claim 1, wherein radiating fins are further mounted on the outer wall of the inner cavity, the outer wall of the phase-change cold storage cavity, and/or the outer wall of the heat dissipation cavity.

5. The heat-release retardative cold conduction device with multi-cavity and multi-phase change according to claim 4, wherein the outside of the radiating fins is coated with a heat-insulating refrigeration coating.

6. The heat-release retardative cold conduction device with multi-cavity and multi-phase change according to claim 5, wherein the heat-insulating refrigeration coating is a composite coating composed of a solar reflective material and a radiative refrigeration material, wherein the solar reflective material includes TiO2, HfO2, Al, Ag, and Cu, and the radiative refrigeration material includes SiO2, SiC, HfO2, aluminum phosphate, phosphite, C-containing elemental materials, and metal oxides such as Al2O3.

7. The heat-release retardative cold conduction device with multi-cavity and multi-phase change according to claim 1, wherein the phase-change cold storage material is composed of a single phase-change material or a plurality of phase-change materials that undergo solid-liquid phase transition.

8. The heat-release retardative cold conduction device with multi-cavity and multi-phase change according to claim 2, wherein the heat insulation material includes aerogel, aluminum silicate fiber, and polyurethane.

9. The heat-release retardative cold conduction device with multi-cavity and multi-phase change according to claim 1, wherein the structure of the heat-release retardative cold conduction device with multi-cavity and multi-phase is made of carbon steel coated with an anti-corrosion coating on its surface.

10. The heat-release retardative cold conduction device with multi-cavity and multi-phase change according to claim 1, wherein the refrigerant is liquid ammonia.

11. A method of calculating transfer heat for a heat-release retardative cold conduction device with multi-cavity and multi-phase change, wherein the heat-release retardative cold conduction device with multi-cavity and multi-phase comprises: an inner cavity, wherein the inner cavity is a hollow sealing structure with an unobstructed central core and two closed ends, and a refrigerant is placed in the cavity; a heat-release retardative cavity encasing a bottom region outside of the inner cavity, wherein a phase-change heat storage material is placed in the heat-release retardative cavity; and a phase-change cold storage cavity encasing the outside of the inner cavity and located in a region above the heat-release retardative cavity, wherein the phase-change cold storage cavity does not completely encase a top region outside of the inner cavity, and a phase-change cold storage material is placed in the phase-change cold storage cavity; wherein the heat-release retardative cavity and a corresponding portion of the inner cavity encased by the heat-release retardative cavity constitute a heat-release retardative evaporation section, the phase-change cold storage cavity and a corresponding portion of the inner cavity encased by the phase-change cold storage cavity constitute an intensive condensation section, and the method comprises at least the steps of determining a first temperature difference based on a difference between the outer wall temperature of the heat-release retardative evaporation section and the outer wall temperature of the intensive condensation section as collected; determining a first heat transfer resistance based on sum values of a heat-conducting resistance from the outer wall to the inner wall of the heat-release retardative evaporation section, an evaporative heat transfer resistance of the inner surface of the heat-release retardative evaporation section, a heat-conducting resistance from the inner wall to the outer wall of the intensive condensation section, a condensational heat transfer resistance of the inner surface of the intensive condensation section, and a heat transfer resistance between the outer wall of the intensive condensation section and the air; and determining a transfer heat of the device based on the first temperature difference and the first heat transfer resistance.

12. The method of calculating transfer heat for a heat-release retardative cold conduction device with multi-cavity and multi-phase change according to claim 11, wherein if the first temperature difference is greater than or equal to a predetermined working temperature difference for actuating the device, the transfer heat of the device is a ratio of the first temperature difference to the first heat transfer resistances, and if the first temperature difference is less than the working temperature difference, the transfer heat of the device is zero.

13. The method of calculating transfer heat for a heat-release retardative cold conduction device with multi-cavity and multi-phase change according to claim 12, wherein parameters of a phase-change cold storage material in the intensive condensation section and parameters of a phase-change heat storage material in the heat-release retardative evaporation section are determined based on the first temperature difference and the first heat transfer resistance.

14. The method of calculating transfer heat for a heat-release retardative cold conduction device with multi-cavity and multi-phase change according to claim 13, wherein a mixing amount of the phase-change cold storage material in the intensive condensation section is represented as: $m \frac{\frac{1}{.Math. R_{i}^{}} (T_{3} - T_{2}) d t}{H}$ where T.sub.2 is the outer wall temperature of the intensive condensation section, T.sub.3 is the outer wall temperature of the heat-release retardative evaporation section, the first temperature difference is T.sub.3T.sub.2, the first heat transfer resistance is $.Math. R_{i}^{},$ H is the latent heat of phase change of the phase-change cold storage material, m is a mixing amount of the phase-change cold storage material, and parameters of the phase-change cold storage material include the mixing amount and the latent heat of phase change of the phase-change cold storage material.

15. The method of calculating transfer heat for a heat-release retardative cold conduction device with multi-cavity and multi-phase change according to claim 13, wherein the phase-change cold storage material has a phase change temperature of less than 1.5 C., and a degree of supercooling of less than 2 C., and parameters of the phase-change cold storage material include the phase change temperature and the degree of supercooling of the phase-change cold storage material.

16. The method of calculating transfer heat for a heat-release retardative cold conduction device with multi-cavity and multi-phase change according to claim 13, wherein a mixing amount of the phase-change heat storage material in the heat-release retardative evaporation section is represented as: $m^{} \frac{\frac{1}{.Math. R_{i}^{}} (T_{3} - T_{2}) d t}{H^{}}$ where T.sub.2 is the outer wall temperature of the intensive condensation section, T.sub.3 is the outer wall temperature of the heat-release retardative evaporation section, the first temperature difference is T.sub.3T.sub.2, the first heat transfer resistance is $.Math. R_{i}^{},$ H is the latent heat of phase change of the phase-change heat storage material, m is a mixing amount of the phase-change heat storage material, and parameters of the phase-change heat storage material include the mixing amount and the latent heat of phase change of the phase-change heat storage material.

17. The method of calculating transfer heat for a heat-release retardative cold conduction device with multi-cavity and multi-phase change according to claim 16, wherein the phase-change heat storage material has a phase change temperature of less than 1.0 C., and a degree of supercooling of less than 2 C., and parameters of the phase-change heat storage material include the phase change temperature and the degree of supercooling of the phase-change heat storage material.

18. A method of calculating transfer heat for a heat-release retardative cold conduction device with multi-cavity and multi-phase change, wherein the heat-release retardative cold conduction device with multi-cavity and multi-phase comprises: an inner cavity, wherein the inner cavity is a hollow sealing structure with an unobstructed central core and two closed ends, and a refrigerant is placed in the cavity; a heat-release retardative cavity encasing a bottom region outside of the inner cavity, wherein a phase-change heat storage material is placed in the heat-release retardative cavity; and a phase-change cold storage cavity encasing the outside of the inner cavity and located in a region above the heat-release retardative cavity, wherein the phase-change cold storage cavity does not completely encase a top region outside of the inner cavity, and a phase-change cold storage material is placed in the phase-change cold storage cavity; wherein the heat-release retardative cavity and a corresponding portion of the inner cavity encased by the heat-release retardative cavity constitute a heat-release retardative evaporation section, and the phase-change cold storage cavity and a corresponding portion of the inner cavity encased by the phase-change cold storage cavity constitute an intensive condensation section; in a condition where the phase-change cold storage cavity does not completely encase a top region outside of the inner cavity and a top portion of the inner cavity constitutes a condensation section, or in a condition where the heat-release retardative cold conduction device with multi-cavity and multi-phase change comprises a heat dissipation cavity which is encased on the outside of the inner cavity and is located in a region above the phase-change cold storage cavity, and the heat dissipation cavity and a corresponding portion of the inner cavity encased by the heat dissipation cavity constitute a condensation section, the method comprises the steps of determining a first temperature difference based on a difference between the outer wall temperature of the heat-release retardative evaporation section and the outer wall temperature of the intensive condensation section as collected; determining a first heat transfer resistance based on sum values of a heat-conducting resistance from the outer wall to the inner wall of the heat-release retardative evaporation section, an evaporative heat transfer resistance of the inner surface of the heat-release retardative evaporation section, a heat-conducting resistance from the inner wall to the outer wall of the intensive condensation section, a condensational heat transfer resistance of the inner surface of the intensive condensation section, and a heat transfer resistance between the outer wall of the intensive condensation section and the air; determining a second temperature difference based on a difference between the outer wall temperature of the heat-release retardative evaporation section and the outer wall temperature of the condensation section as collected; determining a second heat transfer resistance based on sum values of a heat-conducting resistance from the outer wall to the inner wall of the heat-release retardative evaporation section, an evaporative heat transfer resistance of the inner surface of the heat-release retardative evaporation section, a heat-conducting resistance from the inner wall to the outer wall of the condensation section, a condensational heat transfer resistance of the inner surface of the condensation section, and a heat transfer resistance between the outer wall of the condensation section and the air; and determining a transfer heat of the device based on the first temperature difference, the second temperature difference, the first heat transfer resistance and the second heat transfer resistance.

19. The method of calculating transfer heat for a heat-release retardative cold conduction device with multi-cavity and multi-phase change according to claim 18, wherein if both the first temperature difference and the second temperature difference are greater than or equal to a predetermined working temperature difference for actuating the device, the transfer heat of the device is the sum of a ratio of the first temperature difference to the first heat transfer resistances and a ratio of the second temperature difference to the second heat transfer resistance; if the first temperature difference is greater than or equal to the working temperature difference and the second temperature difference is less than the working temperature difference, the transfer heat of the device is the ratio of the first temperature difference to the first heat transfer resistance; if the second temperature difference is greater than or equal to the working temperature difference and the first temperature difference is less than the working temperature difference, the transfer heat of the device is the ratio of the second temperature difference to the second heat transfer resistance; and if both the first temperature difference and the second temperature difference are less than the working temperature difference, the transfer heat of the device is zero.

20. The method of calculating transfer heat for a heat-release retardative cold conduction device with multi-cavity and multi-phase change according to claim 18, wherein heat regulation is performed by a phase-change heat storage material in the heat-release retardative evaporation section during a phase transition process, which comprises: when the outer wall temperature of the condensation section is lower than the outer wall temperature of the intensive condensation section, heat from the heat-release retardative evaporation section is firstly dissipated through the condensation section; and when the outer wall temperature of the condensation section is greater than or equal to the outer wall temperature of the intensive condensation section, heat from the heat-release retardative evaporation section is firstly dissipated by consuming the cold storage capacity of the intensive condensation section.

21. The method of calculating transfer heat for a heat-release retardative cold conduction device with multi-cavity and multi-phase change according to claim 18, wherein refrigeration is performed by a phase-change cold storage material in the intensive condensation section during a phase transition process, which comprises: when the outer wall temperature of the intensive condensation section is reduced to the phase change temperature of the phase-change cold storage material, the phase-change cold storage material undergoes phase transition to store cold until the outer wall temperature of the intensive condensation section is reduced to or even lower than the phase change temperature of the phase-change cold storage material.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The following drawings are provided for illustrative purposes only and merely depict exemplary embodiments of the disclosure. These drawings are provided to facilitate the reader's understanding of the disclosure and should not be considered as limiting to the breadth, scope, or applicability of the disclosure. It should be noted that these drawings are not necessarily drawn to scale for clarity and case of illustration.

[0047] FIG. 1 illustrates a schematic structural diagram of a heat-release retardative cold conduction device with multi-cavity and multi-phase change according to a first embodiment of the present invention;

[0048] FIG. 2 illustrates a schematic structural diagram of a heat-release retardative cold conduction device with multi-cavity and multi-phase change according to a second embodiment of the present invention;

[0049] FIG. 3 illustrates a schematic structural diagram of a heat-release retardative cold conduction device with multi-cavity and multi-phase change according to a third embodiment of the present invention;

[0050] FIG. 4 illustrates a flow diagram of a method of calculating transfer heat for a heat-release retardative cold conduction device with multi-cavity and multi-phase change according to one embodiment of the present invention;

[0051] FIG. 5 illustrates a flow diagram of a method of calculating transfer heat for a heat-release retardative cold conduction device with multi-cavity and multi-phase change according to another embodiment of the present invention.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENT

[0052] In order to make the purpose, solutions, and advantages of the present invention clearer, the present invention will be described in more detail below with reference to the accompanying drawings and specific embodiments. However, the embodiments described below are merely illustrative and should not be construed as limiting the scope of the foregoing subject matter of the invention, and all technologies implemented according to the contents of the invention fall within the scope of the invention.

[0053] In the descriptions of specific embodiments of the invention, terms such as upper, lower, left, right, vertical, horizontal, top, bottom, inner, outer, etc., which indicate orientation or positional relationship, are all expressions based on the orientation or positional relationship shown in the accompanying drawings. These terms of orientation or positional relationship are used only to facilitate and simplify the description of the invention to facilitate a quick understanding of the technical solutions of the invention by those skilled in the art. Accordingly, they do not indicate or imply that a particular device or element must have a particular orientation or be constructed and operated in a particular positional relationship and should therefore not be construed as a limitation of the invention.

[0054] Referring to FIGS. 1 to 3, FIG. 1 illustrates a schematic structural diagram of a heat-release retardative cold conduction device with multi-cavity and multi-phase change according to a first embodiment of the present invention; FIG. 2 illustrates a schematic structural diagram of a heat-release retardative cold conduction device with multi-cavity and multi-phase change according to a second embodiment of the present invention; FIG. 3 illustrates a schematic structural diagram of a heat-release retardative cold conduction device with multi-cavity and multi-phase change according to a third embodiment of the present invention.

[0055] As shown in FIG. 1, according to the first embodiment of the present invention, the heat-release retardative cold conduction device with multi-cavity and multi-phase change comprises at least an inner cavity 1, a heat-release retardative cavity 2 and a phase-change cold storage cavity 3. Wherein, inner cavity 1 is a hollow sealing structure with an unobstructed central core and two closed ends, refrigerant 10 is placed in the cavity, and the hollow sealing structure is used to store refrigerant 10 and provide a convective heat transfer channel for refrigerant 10 when it is converted between liquid and gas phases. Heat-release retardative cavity 2 is encased on a bottom region outside of inner cavity 1, and phase-change heat storage material 20 is placed in heat-release retardative cavity 2, where phase-change heat storage material 20 undergoes phase transition at low temperatures to regulate the spatiotemporal distributions of heat. Phase-change cold storage cavity 3 is encased on the outside of inner cavity 1 and is located in a region above heat-release retardative cavity 2. Specifically, heat insulation cavity 5 is connected to heat-release retardative cavity 2 and is located above heat-release retardative cavity 2, while phase-change cold storage cavity 3 is connected to heat insulation cavity 5 and is further located above heat insulation cavity 5. In addition, a phase-change cold storage material 30 is placed in phase-change cold storage cavity 3, where phase-change cold storage material 30 undergoes phase transition at low temperatures to store cold and cool down. In this embodiment, phase-change cold storage cavity 3 completely encases a top region outside of inner cavity 1.

[0056] In this embodiment, heat-release retardative cavity 2 and a corresponding portion of inner cavity 1 encased by heat-release retardative cavity 2 constitute a heat-release retardative evaporation section A, and phase-change cold storage cavity 3 and a corresponding portion of inner cavity 1 encased by phase-change cold storage cavity 3 constitute an intensive condensation section B.

[0057] In practical applications, the permafrost is divided into a permafrozen layer, and an active layer, in order from the bottom to the top, and a filling layer is provided over the active layer. When the heat-release retardative cold conduction device with multi-cavity and multi-phase change is used in permafrost engineering, heat-release retardative evaporation section A will be buried in the permafrozen layer of the permafrost to a depth of 0.5 m below the active layer, and the spatiotemporal distributions of heat is regulated by phase-change heat storage material 20 in heat-release retardative cavity 2 undergoing phase transition at low temperatures. Meanwhile, intensive condensation section B is in the atmospheric environment, where phase-change cold storage material 30 in intensive condensation section B undergoes phase transition when its phase change temperature is lower than the permafrost temperature, thereby achieving cold storage and cooling down and providing a low-temperature condition for continuous cold conduction. Specifically, when a difference value between the outer wall temperature of heat-release retardative evaporation section A and the outer wall temperature of intensive condensation section B (i.e., the first temperature difference) satisfies a predetermined working temperature difference for actuating the device, refrigerant 10 in heat-release retardative evaporation section A absorbs the heat from the permafrost layer and then evaporates to form a vapor that rises toward intensive condensation section B. Subsequently, the vapor is liquefied and cooled in intensive condensation section B to dissipate heat, and the liquid formed flows back to the evaporation section under its own gravity. In addition, heat-release retardative evaporation section A regulates the spatiotemporal distributions of heat by a phase transition at low temperatures. In this embodiment, the ground temperature of permafrost is regulated by heat changes of inner cavity 1, heat-release retardative cavity 2, phase-change cold storage cavity 3, and so on, thereby preventing the problem of engineering damages caused by the cold conduction being unevenly distributed in both space and time and being discontinuously distributed in time.

[0058] Furthermore, in this embodiment, referring further to FIG. 1, radiating fins 6 are also provided on the outer wall of phase-change cold storage cavity 3, which facilitates heat dissipation. Specifically, when used in permafrost engineering, radiating fins 6 can dissipate heat from permafrost areas.

[0059] Furthermore, referring further to FIG. 1, the outside of radiating fins 6 is also coated with a heat-insulating refrigeration coating 60, which utilizes the principles of heat reflective cooling and radiative refrigeration to prevent the heat disturbance of sunlight on phase-change cold storage material 30 and to provide a radiative refrigeration effect.

[0060] In this embodiment, intensive condensation section B does not rely on an external energy supply to drive refrigeration but instead adopts a self-driven refrigeration control mode. Phase-change cold storage material 30, radiating fins 6 and heat-insulating refrigeration coating 60 provided in intensive condensation section B serve as a self-driven means to improve the actual refrigeration, which occurs phase-change cold storage, heat transfer between the phase-change units, heat dissipation of radiating fins 6, and heat insulation and refrigeration of heat-insulating refrigeration coating 60 in a horizontal direction. As a result, low-temperature cold is conducted to phase-change cold storage material 30 inside phase-change cold storage cavity 3 via heat-insulating refrigeration coating 60 to promote phase-change cold storage material 30 undergoing phase transition to store cold and to provide low-temperature conditions for the device to work continuously, so that the problem of engineering damages caused by the cold conduction being unevenly distributed in both space and time and being discontinuously distributed in time can be solved to some extent.

[0061] Specifically, at night, phase-change cold storage material 30 undergoes phase transition to store cold while the radiative refrigeration material undergoes heat radiative cooling in all directions when the atmospheric temperature is reduced to the phase change temperature of phase-change cold storage material 30. Finally, the outer wall temperature of intensive condensation section B is reduced until it is lower than the phase change temperature of phase-change cold storage material 30, at which time a maximum temperature difference is formed between the temperature of intensive condensation section B and the temperature of heat-release retardative evaporation section A, thus the actual power of the device is improved.

[0062] During the daytime, heat-insulating refrigeration coating 60 undergoes surface cooling by using a high reflectivity of the heat reflection material to sunlight, and on the other hand, it undergoes radiative heat dissipation by using the radiative refrigeration material during an atmospheric window having a certain wavelength, thereby keeping the outer wall temperature of intensive condensation section B almost unchanged. Meanwhile, the temperature difference formed between the outer wall temperature of intensive condensation section B and the outer wall temperature of heat-release retardative evaporation section A is greater than a working temperature difference for actuating the device, and heat from heat-release retardative evaporation section A is transferred to phase-change cold storage material 30 in phase-change cold storage cavity 3, which promotes phase-change cold storage material 30 undergoing phase transition to absorb heat. When the atmospheric temperature is decreased, phase-change cold storage material 30 releases heat and stores cold, and the released heat is dissipated by heat conduction between the cold storage units, radiating fins 6, and heat radiation of the radiative refrigeration material.

[0063] Therefore, according to this embodiment, since intensive condensation section B stores sufficient cold by phase change at low temperatures, not only the limitations of discontinuous working time and low actual efficacy of the thermosyphon in the cold season are eliminated, but also the time for the working temperature difference required for actuating the heat-release retardative cold conduction device with multi-cavity and multi-phase change in the beginning and end periods of the cold season is ensured so that both the actual efficiency of the cold conduction and the working time are improved. During the warm season, intensive condensation section B utilizes the environment of large temperature difference between day and night on the plateau, when the temperature at night drops to the phase change temperature, phase-change cold storage material 30 undergoes phase transition to store cold, thereby achieving the reverse transfer of heat inside the permafrost to the atmospheric environment, and achieving the spatiotemporal homogeneity and enhanced cold conduction of the permafrost.

[0064] As shown in FIG. 2, according to the second embodiment of the present invention, the heat-release retardative cold conduction device with multi-cavity and multi-phase change comprises at least an inner cavity 1, a heat-release retardative cavity 2, and a phase-change cold storage cavity 3. Wherein, inner cavity 1 is a hollow scaling structure with an unobstructed central core and two closed ends, and refrigerant 10 is placed in the cavity, and the hollow sealing structure is used to store refrigerant 10 and provide a convective heat transfer channel for refrigerant 10 when it is converted between liquid and gas phases. Heat-release retardative cavity 2 is encased on a bottom region outside of inner cavity 1, and phase-change heat storage material 20 is placed in heat-release retardative cavity 2, where phase-change heat storage material 20 undergoes phase transition at low temperatures to regulate the spatiotemporal distributions of heat. Phase-change cold storage cavity 3 is encased on the outside of inner cavity 1 and is located in a region above heat-release retardative cavity 2. Specifically, heat insulation cavity 5 is connected to heat-release retardative cavity 2 and is located above heat-release retardative cavity 2, while phase-change cold storage cavity 3 is connected to heat insulation cavity 5 and is further located above heat insulation cavity 5. In addition, a phase-change cold storage material 30 is placed in phase-change cold storage cavity 3, where phase-change cold storage material 30 undergoes phase transition at low temperatures to store cold and cool down. In this embodiment, phase-change cold storage cavity 3 of the heat-release retardative cold conduction device with multi-cavity and multi-phase change does not completely encase a top region outside of the inner cavity 1.

[0065] Furthermore, in this embodiment, radiating fins 6 are also provided on the outer wall of phase-change cold storage cavity 3, as well as on a top region outside of inner cavity 1, where radiating fins 6 facilitate heat dissipation. The outside of radiating fins 6 is also coated with a heat-insulating refrigeration coating 60, which utilizes the principles of heat-reflective cooling and radiative refrigeration to prevent the heat disturbance of sunlight on phase-change cold storage material 30 and to provide a radiative refrigeration effect.

[0066] This embodiment differs from the preceding embodiment in that phase-change cold storage cavity 3 of the heat-release retardative cold conduction device with multi-cavity and multi-phase change does not completely encase the top region outside of inner cavity 1, while heat-release retardative cavity 2 and a corresponding portion of inner cavity 1 encased by the heat-release retardative cavity 2 constitute a heat-release retardative evaporation section A, phase-change cold storage cavity 3 and a corresponding portion of inner cavity 1 encased by phase-change cold storage cavity 3 constitute an intensive condensation section B, and a top portion of inner cavity 1 constitutes a condensation section C.

[0067] In practical applications, when the heat-release retardative cold conduction device with multi-cavity and multi-phase change is used in permafrost engineering, heat-release retardative evaporation section A will be buried in the permafrozen layer of the permafrost to a depth of 0.5 m below the active layer. Meanwhile, both intensive condensation section B and condensation section C are in the atmospheric environment, where phase-change heat storage material 20 in heat-release retardative cavity 2 undergoes phase transition at low temperatures to regulate the spatiotemporal distribution of heat, thereby achieving cold storage and cooling down and providing a low-temperature condition for continuous cold conduction.

[0068] In this embodiment, heat is transferred from the permafrost layer to the atmospheric environment along with a vertical direction under the effect of a double temperature difference between heat-release retardative evaporation section A and intensive condensation section B, and between heat-release retardative evaporation section A and condensation section C. Specifically, when the difference between the outer wall temperature of heat-release retardative evaporation section A and the outer wall temperature of intensive condensation section B (i.e., the first temperature difference) satisfies a predetermined working temperature difference for actuating the device, or when the difference between the outer wall temperature of heat-release retardative evaporation section A and the outer wall temperature of intensive condensation section B (i.e., the second temperature difference) satisfies a working temperature difference for actuating the device, refrigerant 10 in heat-release retardative evaporation section A absorbs heat from the permafrost layer and then evaporates to form vapor that rises toward intensive condensation section B or condensation section C. Subsequently, the vapor is liquefied and cooled to dissipate heat in intensive condensation section B or condensation section C, and the liquid formed flows back to the evaporation section under its own gravity. In addition, heat-release retardative evaporation section A undergoes phase transition at low temperatures to regulate the spatiotemporal distribution of heat.

[0069] In this embodiment, when the outer wall temperature of condensation section C is greater than the outer wall temperature of intensive condensation section B, heat from heat-release retardative evaporation section A is firstly dissipated by consuming the cold storage capacity of intensive condensation section B, and when the outer wall temperature of condensation section C is lower than the outer wall temperature of intensive condensation section B, heat from heat-release retardative evaporation section A is firstly dissipated through condensation section C.

[0070] In the cold season, conventional thermosyphon is unable to achieve the working temperature difference for actuating the device due to the influence of atmospheric temperature and other factors, so the working time has a discontinuity, and the actual working time is about of the working cycle. Moreover, during the beginning and end periods of the cold season, conventional thermosyphon will experience problems that either the time at the temperature difference for actuating the device is too short or the temperature difference for actuating the device cannot be achieved, resulting in low-efficiency utilization or failure to work. For these problems, according to this embodiment, since intensive condensation section B stores sufficient cold by phase transition at low temperatures, not only the limitations of discontinuous working time and low actual efficacy of the thermosyphon in the cold season are eliminated, but also the time for the working temperature difference required for actuating the thermosyphon in the beginning and end periods of the cold season is ensured, so that the actual efficiency of the cold conduction and the working time are improved. During the warm season, intensive condensation section B utilizes the environment of a large temperature difference between day and night on the plateau, when the temperature at night drops to the phase change temperature, phase-change cold storage material 30 undergoes phase transition to store cold, thereby achieving the reverse transfer of heat inside the permafrost to the atmospheric environment, and controlling the temperature rises of the permafrost in real-time.

[0071] Specifically, at night, phase-change cold storage material 30 undergoes phase transition to store cold while the radiative refrigeration material undergoes heat radiative cooling when the outer wall temperature of intensive condensing section B is reduced to the phase change temperature of phase-change cold storage material 30. Finally, the outer wall temperature of intensive condensation section B is reduced to or even lower than the phase change temperature of phase-change cold storage material 30, at which time the outer wall temperature of condensing section C is higher than the outer wall temperature of intensive condensing section B, and a maximum temperature difference is formed between the temperature of intensive condensation section B and the temperature of heat-release retardative evaporation section A, thus the actual power of the device is improved.

[0072] During the daytime, heat-insulating refrigeration coating 60 undergoes surface cooling by using a high reflectivity of the heat reflection material to sunlight, and on the other hand, it undergoes radiative heat dissipation by using the radiative refrigeration material during an atmospheric window having a certain wavelength, thereby keeping the outer wall temperature of intensive condensation section B almost unchanged. Meanwhile, the temperature difference formed between the outer wall temperature of intensive condensation section B and the outer wall temperature of heat-release retardative evaporation section A is greater than a working temperature difference for actuating the device, and heat from heat-release retardative evaporation section A is transferred to phase-change cold storage material 30 in phase-change cold storage cavity 3, which promotes phase-change cold storage material 30 undergoing phase transition to absorb heat. When the atmospheric temperature is decreased, phase-change cold storage material 30 releases heat and stores cold, and the released heat is dissipated by heat conduction between the cold storage units, radiating fins 6, and heat radiation of the radiative refrigeration material.

[0073] In this embodiment, heat is transferred from the permafrost layer to the atmospheric environment along with a vertical direction under the effect of a double temperature difference between heat-release retardative evaporation section A and intensive condensation section B, and between heat-release retardative evaporation section A and condensation section C, so that the regulation efficiency of the device on heat is further improved, and the problem of engineering damages caused by the cold conduction being unevenly distributed in both space and time and being discontinuously distributed in time is prevented.

[0074] As shown in FIG. 3, according to the third embodiment of the present invention, the heat-release retardative cold conduction device with multi-cavity and multi-phase change comprises at least an inner cavity 1, a heat-release retardative cavity 2, a phase-change cold storage cavity 3, and a heat dissipation cavity 4. Wherein inner cavity 1 is a hollow sealing structure with an unobstructed central core and two closed ends, and refrigerant 10 is placed in the cavity, and the hollow sealing structure is used to store refrigerant 10 and provide a convective heat transfer channel for refrigerant 10 when it is converted between liquid and gas phases. Heat-release retardative cavity 2 is encased on a bottom region outside of inner cavity 1, and phase-change heat storage material 20 is placed in heat-release retardative cavity 2, where phase-change heat storage material 20 undergoes phase transition at low temperatures to regulate the spatiotemporal distributions of heat. Phase-change cold storage cavity 3 is encased on the outside of inner cavity 1 and is located in a region above heat-release retardative cavity 2. Specifically, heat insulation cavity 5 is connected to heat-release retardative cavity 2 and is located above heat-release retardative cavity 2, while phase-change cold storage cavity 3 is connected to heat insulation cavity 5 and is further located above heat insulation cavity 5. In addition, a phase-change cold storage material 30 is placed in phase-change cold storage cavity 3, where phase-change cold storage material 30 undergoes phase transition at low temperatures to store cold and cool down. Heat dissipation cavity 4 is encased on the outside of inner cavity 1 and is located in a region above phase-change cold storage cavity 3, which can be connected to phase-change cold storage cavity 3, and a unidirectional heat conductive material 40 is placed in heat dissipation cavity 4.

[0075] In this embodiment, heat-release retardative cavity 2 and a corresponding portion of inner cavity 1 encased by heat-release retardative cavity 2 constitute a heat-release retardative evaporation section A, phase-change cold storage cavity 3 and a corresponding portion of inner cavity 1 encased by phase-change cold storage cavity 3 constitute an intensive condensation section B, and heat dissipation cavity 4 and a corresponding portion of inner cavity 1 encased by heat dissipation cavity 4 constitute a condensation section C.

[0076] Compared to the second embodiment described above, the heat-release retardative cold conduction device with multi-cavity and multi-phase change is further provided with a heat dissipation cavity 4, and a unidirectional heat conductive material 40 is stored in heat dissipation cavity 4 to further improve the outward heat conductive effect of condensation section C.

[0077] Furthermore, in this embodiment, radiating fins 6 are also provided on the outer wall of phase-change cold storage cavity 3 and the outer wall of heat dissipation cavity 4, where radiating fins 6 facilitate heat dissipation. The outside of radiating fin 6 is also coated with a heat-insulating refrigeration coating 60, which utilizes the principles of heat-reflective cooling and radiative refrigeration to prevent the heat disturbance of sunlight on phase-change cold storage material 30 and to provide a radiative refrigeration effect.

[0078] Furthermore, this embodiment is the same as the second embodiment described above in that, heat is transferred from the permafrost layer to the atmospheric environment along with a vertical direction under the effect of a double temperature difference between heat-release retardative evaporation section A and intensive condensation section B, and between heat-release retardative evaporation section A and condensation section C, so that the regulation efficiency of the device on heat is further improved, and the problem of engineering damages caused by the cold conduction being unevenly distributed in both space and time and being discontinuously distributed in time is prevented. The specific process is the same as in the second embodiment, so there will be no repetition here.

[0079] Furthermore, according to other embodiments of the present invention, referring further to FIGS. 1 to 3, the heat-release retardative cold conduction device with multi-cavity and multi-phase change may be further provided with a heat insulation cavity 5, which is encased on the outside of the inner cavity 1 and is located between heat-release retardative cavity 2 and phase-change cold storage cavity 3. Moreover, two ends of heat insulation cavity 5 are respectively connected to heat-release retardative cavity 2 and phase-change cold storage cavity 3, and a heat insulation material 50 is placed in heat insulation cavity 5. Heat insulation cavity 5 and a corresponding portion of inner cavity 1 encased by heat insulation cavity 5 constitute a heat insulation section D. In practical applications, heat insulation section D is located in a portion above 0.5 m of the active layer up to the filling layer in the permafrost, wherein no heat exchange occurs in heat insulation section D. In some embodiments, heat insulation material 50 includes acrogel, aluminum silicate fiber, polyurethane or the like, but the present invention is not limited thereto.

[0080] Furthermore, in some embodiments, liquid ammonia may be used as refrigerant 10, but the present invention is not limited thereto. Refrigerant 10 may also be other materials such as, for example, organic materials such as 3-heptanone, decane, 2-heptanone, diethylene glycol, n-octane, mercury, and composite low-temperature phase-change materials formed by mixing low melting point molten salts such as CaCl.sub.2, MgCl.sub.2, KCl or the like. In addition, a certain amount of gases such as inert gases and carbon dioxide may also be added to the inner cavity.

[0081] Furthermore, in some embodiments, phase-change cold storage material 30 is composed of a single phase-change material or a plurality of phase-change materials that undergo solid-liquid phase transition, and phase-change cold storage material 30 undergoes phase transition at low temperatures to store cold and cool down.

[0082] In some embodiments, heat-insulating refrigeration coating 60 is a composite coating composed of a solar reflective material and a radiative refrigeration material, wherein the solar reflective material includes TiO.sub.2, HfO.sub.2, Al, Ag, Cu, or the like, which reduces the surface temperature of the device by sunlight reflection, while the radiative refrigeration material includes SiO.sub.2, SiC, aluminum phosphate, phosphite, C-containing elemental materials, and metal oxides such as Al.sub.2O.sub.3 or the like, which performs radiative refrigeration through an atmospheric window having a wavelength band of 8 to 13 m. In addition, with respect to the materials used for heat-insulating refrigeration coating 60, it should be noted that the present invention is not limited to the above-described materials.

[0083] Furthermore, in some embodiments, referring further to FIGS. 1 to 3, a desired material used for the structure of the heat-release retardative cold conduction device with multi-cavity and multi-phase change is carbon steel coated with an anti-corrosion coating 70, wherein anti-corrosion coating 70 prevents corrosion of the carbon steel due to moisture and ions.

[0084] Furthermore, in some embodiments, in order to monitor the outer wall temperatures of each section in real time, temperature sensors may also be provided in each section of the heat-release retardative cold conduction device with multi-cavity and multi-phase change, such as heat-release retardative A, heat insulation section D, intensive condensation section B, condensation section C, and so on.

[0085] Furthermore, referring to FIGS. 4 to 5, another aspect of the present invention further provides a method of calculating transfer heat for a heat-release retardative cold conduction device with multi-cavity and multi-phase change, wherein FIG. 4 shows a flow diagram of the method of calculating transfer heat for the heat-release retardative cold conduction device with multi-cavity and multi-phase change according to one embodiment of the present invention, FIG. 5 shows a flow diagram of the method of calculating transfer heat for the heat-release retardative cold conduction device with multi-cavity and multi-phase change according to another embodiment of the present invention.

[0086] Referring to FIG. 4, one embodiment of the present invention is based on the heat-release retardative cold conduction device with multi-cavity and multi-phase change as shown in FIG. 1. In the heat-release retardative cold conduction device with multi-cavity and multi-phase change, heat-release retardative cavity 2 and a corresponding portion of inner cavity 1 encased by heat-release retardative cavity 2 constitute a heat-release retardative evaporation section A, and phase-change cold storage cavity 3 and a corresponding portion of inner cavity 1 encased by phase-change cold storage cavity 3 constitute an intensive condensation section B. Accordingly, the method of calculating transfer heat for the heat-release retardative cold conduction device with multi-cavity and multi-phase change comprises at least the following steps of S11 to S13.

[0087] In step S11, a first temperature difference is determined based on a difference between the outer wall temperature of heat-release retardative evaporation section A and the outer wall temperature of intensive condensation section B as collected.

[0088] In step S12, a first heat transfer resistance is determined based on sum values of a heat-conducting resistance from the outer wall to the inner wall of heat-release retardative evaporation section A, an evaporative heat transfer resistance of the inner surface of heat-release retardative evaporation section A, a heat-conducting resistance from the inner wall to the outer wall of intensive condensation section B, a condensational heat transfer resistance of the inner surface of intensive condensation section B, and a heat transfer resistance between the outer wall of intensive condensation section B and the air.

[0089] In step S13, a transfer heat of the device is determined based on the first temperature difference and the first heat transfer resistance.

[0090] Wherein, if the first temperature difference is greater than or equal to a predetermined working temperature difference for actuating the device, the transfer heat of the heat-release retardative cold conduction device with multi-cavity and multi-phase change is a ratio of the first temperature difference to the first heat transfer resistances, and if the first temperature difference is less than the working temperature difference, the transfer heat of the heat-release retardative cold conduction device with multi-cavity and multi-phase change is zero.

[0091] That is, the transfer heat of the heat-release retardative cold conduction device with multi-cavity and multi-phase change can be represented by the following equation.

[00005] $q = {\begin{matrix} \frac{1}{.Math. R_{i}^{}} (T_{3} - T_{2}) & (T_{3} - T_{2} T) \\ 0 & (T_{3} - T_{2} < T) \end{matrix}$

Where q is a transfer heat of the device,

[00006] $.Math. R_{i}^{}$

is the first heat transfer resistance and

[00007] $.Math. R_{i}^{} = R_{1} + R_{2} + R_{3}^{} + R_{4}^{} + R_{5}^{}, R_{1}$

is the heat-conducting resistance from the outer wall to the inner wall of heat-release retardative evaporation section A, R.sub.2 is the evaporative heat transfer resistance of the inner surface of heat-release retardative evaporation section A,

[00008] $R_{3}^{}$

is the heat-conducting resistance from the inner wall to the outer wall of intensive condensation section B,

[00009] $R_{4}^{}$

is the condensational heat transfer resistance of the inner surface of intensive condensation section B,

[00010] $R_{5}^{}$

is the heat transfer resistance between the outer wall of intensive condensation section B and the air, T.sub.2 is the outer wall temperature of intensive condensation section B, T.sub.3 is the outer wall temperature of heat-release retardative evaporation section A, the first temperature difference is T.sub.3T.sub.2, T is the working temperature difference for actuating the device. Meanwhile, Q is an annual refrigerating capacity of the heat-release retardative cold conduction device with multi-cavity and multi-phase change and

[00011] $Q =_{t_{1}}^{t_{2}} q d t,$

where t.sub.1 segment is the refrigeration onset time of the cold conduction device in a year, t.sub.2 segment is the refrigeration end time of the cold conduction device in a year.

[0092] Furthermore, referring to FIG. 5, if the heat-release retardative cold conduction device with multi-cavity and multi-phase change further comprises a condensation section C, as shown in FIGS. 2 to 3, i.e., in a condition where phase-change cold storage cavity 3 does not completely encase a top region outside of inner cavity 1, and a top portion of inner cavity 1 constitutes a condensation section C, and/or in a condition where the heat-release retardative cold conduction device with multi-cavity and multi-phase comprises a heat dissipation cavity 4 that is encased on the outside of inner cavity 1 and is located in a region above phase-change cold storage cavity 3, and heat dissipation cavity 4 and a corresponding portion of inner cavity 1 encased by heat dissipation cavity 4 constitute a condensation section C, the method of calculating transfer heat for the heat-release retardative cold conduction device with multi-cavity and multi-phase change comprises at least the following steps of S21 to S25.

[0093] In step S21, a first temperature difference is determined based on a difference between the outer wall temperature of heat-release retardative evaporation section A and the outer wall temperature of intensive condensation section B as collected.

[0094] In step S22, a second temperature difference is determined based on a difference between the outer wall temperature of heat-release retardative evaporation section A and the outer wall temperature of condensation section C as collected.

[0095] In step S23, a first heat transfer resistance is determined based on sum values of a heat-conducting resistance from the outer wall to the inner wall of heat-release retardative evaporation section A, an evaporative heat transfer resistance of the inner surface of heat-release retardative evaporation section A, a heat-conducting resistance from the inner wall to the outer wall of intensive condensation section B, a condensational heat transfer resistance of the inner surface of intensive condensation section B, and a heat transfer resistance between the outer wall of intensive condensation section B and the air.

[0096] In step S24, a second heat transfer resistance is determined based on sum values of a heat-conducting resistance from the outer wall to the inner wall of heat-release retardative evaporation section A, an evaporative heat transfer resistance of the inner surface of heat-release retardative evaporation section A, a heat-conducting resistance from the inner wall to the outer wall of condensation section C, a condensational heat transfer resistance of the inner surface of condensation section C, and a heat transfer resistance between the outer wall of condensation section C and the air.

[0097] In step S25, a transfer heat of the device is determined based on the first temperature difference, the second temperature difference, the first heat transfer resistance and the second heat transfer resistance.

[0098] Wherein, if both the first temperature difference and the second temperature difference are greater than or equal to the working temperature difference, the transfer heat of the heat-release retardative cold conduction device with multi-cavity and multi-phase change is the sum of a ratio of the first temperature difference to the first heat transfer resistances and a ratio of the second temperature difference to the second heat transfer resistance. If the first temperature difference is greater than or equal to the working temperature difference and the second temperature difference is less than the working temperature difference, the transfer heat of the heat-release retardative cold conduction device with multi-cavity and multi-phase change is the ratio of the first temperature difference to the first heat transfer resistance. If the second temperature difference is greater than or equal to the working temperature difference and the first temperature difference is less than the working temperature difference, the transfer heat of the heat-release retardative cold conduction device with multi-cavity and multi-phase change is the ratio of the second temperature difference to the second heat transfer resistance. If both the first temperature difference and the second temperature difference are less than the working temperature difference, the transfer heat of the heat-release retardative cold conduction device with multi-cavity and multi-phase change is zero.

[0099] That is, the transfer heat of the heat-release retardative cold conduction device with multi-cavity and multi-phase change can be represented by the following equation.

[00012] $q = {\begin{matrix} \frac{1}{.Math. R_{i}} (T_{3} - T_{1}) + \frac{1}{.Math. R_{i}^{}} (T_{3} - T_{2}) & (T_{3} - T_{1} T & T_{3} - T_{1} T) \\ \frac{1}{.Math. R_{i}^{}} (T_{3} - T_{2}) & (T_{3} - T_{1} < T & T_{3} - T_{2} T) \\ \frac{1}{.Math. R_{i}} (T_{3} - T_{1}) & (T_{3} - T_{1} T & T_{3} - T_{2} < T) \\ 0 & (T_{3} < T_{1} + T & T_{3} < T_{2} + T) \end{matrix}$

Where q is a transfer heat of the device,

[00013] $.Math. R_{i}^{}$

is the first heat transfer resistance and

[00014] $.Math. R_{i}^{} = R_{1} + R_{2} + R_{3}^{} + R_{4}^{} + R_{5}^{},$

R.sub.i is the second heat transfer resistance and R.sub.i=R.sub.1+R.sub.2+R.sub.3+R.sub.4+R.sub.5, R.sub.1 is the heat-conducting resistance from the outer wall to the inner wall of heat-release retardative evaporation section A, R.sub.2 is evaporative heat transfer resistance of the inner surface of heat-release retardative evaporation section A, R.sub.3 is the heat-conducting resistance from the inner wall to the outer wall of condensation section C, R.sub.4 is the evaporative heat transfer resistance of the inner surface of condensation section C, R.sub.5 is the heat transfer resistance between the outer wall of condensation section C and the air,

[00015] $R_{3}^{}$

is the heat-conducting resistance from the inner wall to the outer wall of intensive condensation section B,

[00016] $R_{4}^{}$

is the condensational heat transfer resistance of the inner surface of intensive condensation section B,

[00017] $R_{5}^{}$

is the heat transfer resistance between the outer wall of intensive condensation section B and the air, T.sub.2 is the outer wall temperature of intensive condensation section B, T.sub.3 is the outer wall temperature of heat-release retardative evaporation section A, T.sub.1 is the outer wall temperature of condensation section C, T.sub.3T.sub.2 is the first temperature difference, T.sub.3T.sub.1 is the second temperature difference, T is the working temperature difference for actuating the device. Meanwhile, Q is an annual refrigerating capacity of the heat-release retardative cold conduction device with multi-cavity and multi-phase change and

[00018] $Q =_{t_{1}}^{t_{2}} qdt,$

where t.sub.1 segment is the refrigeration onset time of the cold conduction device in a year, t.sub.2 segment is the refrigeration end time of the cold conduction device in a year.

[0100] It should be noted that according to the method of calculating the transfer heat in the two embodiments described above, the execution of each of the steps S11 to S12 as well as the execution of each of the steps S21 to S24 are not intended to be sequentially limited, and each of the steps does not have a specific sequential relationship.

[0101] In addition, according to the above two embodiments, the method of calculating transfer heat for a heat-release retardative cold conduction device with multi-cavity and multi-phase change may further comprise the step of determining parameters of phase-change cold storage material 30 in intensive condensation section B and parameters of phase-change heat storage material 20 in heat-release retardative evaporation section A based on the first temperature difference and the first heat transfer resistance.

[0102] Wherein, parameters of phase-change cold storage material 30 include the mixing amount, the latent heat of phase change, the phase change temperature, the degree of supercooling of phase-change cold storage material 30 or the like. Wherein, the mixing amount of phase-change cold storage material 30 in intensive condensation section B is specifically represented as:

[00019] $m \frac{\frac{1}{.Math. R_{i}^{}} (T_{3} - T_{2}) d t}{H}$

where H is the latent heat of phase change of phase-change cold storage material 30, and m is the mixing amount of phase-change cold storage material 30.

[0103] In some embodiments, phase-change cold storage material 30 has a phase change temperature of less than 1.5 C. and a degree of supercooling of less than 2 C., but the present invention is not limited thereto.

[0104] On the other hand, parameters of phase-change heat storage material 20 include the mixing amount, the latent heat of phase change, the phase change temperature, the degree of supercooling of phase-change heat storage material 20 or the like. Wherein, the mixing amount of phase-change heat storage material 20 in heat-release retardative evaporation section A is specifically represented as:

[00020] $m^{} \frac{\frac{1}{.Math. R_{i}^{}} (T_{3} - T_{2}) d t}{H^{}}$

where H is the latent heat of phase change of phase-change heat storage material 20, and m is the mixing amount of phase-change heat storage material 20.

[0105] In some embodiments, phase-change heat storage material 20 has a phase change temperature of less than 1.0 C. and a degree of supercooling of less than 2 C., but the present invention is not limited thereto.

[0106] In summary, the heat-release retardative cold conduction device with multi-cavity and multi-phase change provided by the present invention utilizes the principles of low-temperature phase-change energy storage, heat reflective cooling and radiative refrigeration, and regulates the temperature through heat changes in inner cavity 1, heat-release retardative cavity 2, phase-change cold storage cavity 3 or the like. Phase-change heat storage material 20 in heat-release retardative cavity 2 undergoes phase transition at low temperature to regulate heat distribution in space and time, and phase-change cold storage material 30 in phase-change cold storage cavity 3 undergoes phase transition at low temperature to store cold, so as to provide low-temperature conditions for continuous cold conduction. On the other hand, heat-insulating refrigeration coating 60 not only prevents the heat disturbance of sunlight on phase-change cold storage material 30 but also provides a radiative refrigeration effect. In addition, according to the heat-release retardative cold conduction device with multi-cavity and multi-phase change of the present invention, the regulation efficiency of the device on heat is improved, and the problem of engineering damages caused by the cold conduction being unevenly distributed in both space and time and being discontinuously distributed in time is eliminated. In addition, both heat-release retardative evaporation section A and intensive condensation section B of the present invention do not rely on solar energy, wind energy and other resources, which have the advantages of energy saving, low carbon and environmentally friendly, and provide a new idea for permafrost engineering in seasons or areas where solar energy, wind energy and other resources are not abundant.

[0107] All the above are only some of the preferred embodiments of the invention and are not intended to limit the invention. The invention may also have a variety of other embodiments, and without departing from the spirit and substance of the invention, a person skilled in the art may make various changes and modifications in accordance with the invention, but such changes and modifications shall fall within the protection scope of the invention.

HEAT-RELEASE RETARDATIVE COLD CONDUCTION DEVICE WITH MULTI-CAVITY AND MULTI-PHASE CHANGE AND METHOD OF CALCULATING TRANSFER HEAT THEREOF

Inventors

Cpc classification

Classification Explorer

F28D15/02

MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING

Classification Explorer

F24T10/40

MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING

International classification

Classification Explorer

F24T10/40

MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING

Abstract

Claims

Description