Dynamic thermal management module and thermal management system based on phase change thermal storage and gravity heat pipe

Abstract

The utility model relates to a kind of dynamic thermal management module based on phase change heat storage and gravity heat pipe, from bottom to top successively including integrally-formed heat source box, phase change heat storage box and heat dissipation box, heat source is provided in heat source box, phase change heat storage box is set in heat source box top, including upper narrow lower wide and hollow phase change material special-shaped block and the gravity heat pipe inserted in phase change material special-shaped block, phase change material special-shaped block is encapsulated with high-expansion-coefficient phase change material, when high-expansion-coefficient phase change material is different state, phase change material special-shaped block high-expansion-coefficient phase change material and gravity heat pipe evaporation section contact degree is different;Solve the existing thermal management equipment in operation faces instantaneous thermal shock, supercooling in low temperature environment and in confined space difficult to realize passive thermal management, heat exchange efficiency is low, heat preservation and heat dissipation mode dynamic switching difficult, affect its application range problem.

Description

Technical Field

[0001] This utility model belongs to the field of dynamic passive thermal management technology, and relates to a dynamic thermal management module and thermal management system based on phase change thermal storage and gravity heat pipe. Background Technology

[0002] With the continuous advancement of science and technology, key fields such as energy storage, electronic communications, and aerospace are rapidly developing towards high power density and miniaturized integration. However, this trend also brings new challenges: equipment generates short-term high heat during operation and is affected by ambient temperature during idle periods. These factors pose significant threats to the safe and reliable operation of the equipment. Therefore, the demand for efficient and compact thermal management modules is increasingly urgent, which is crucial for maintaining equipment operation within a safe temperature range.

[0003] Currently, common thermal management methods employ air or liquid cooling, primarily relying on convective heat transfer to remove or provide heat. However, this approach has significant limitations: firstly, its convective heat transfer coefficient is low, resulting in less than ideal heat transfer efficiency; secondly, the equipment is relatively large and typically requires active energy-consuming devices such as fans or water pumps to improve heat transfer efficiency, making it unsuitable for high-power, compact equipment. Meanwhile, phase change materials, due to their ability to absorb or release large amounts of latent heat during phase change, can effectively mitigate temperature fluctuations and instantaneous thermal shocks, but their low thermal conductivity leads to slow heat transfer, easily causing localized overheating or undercooling, thus affecting the uniformity of equipment temperature. While gravity heat pipes possess extremely high equivalent thermal conductivity, enabling rapid heat transfer through the evaporation-condensation of the working fluid and gravity reflux, and are simple in structure and low in cost, their limited heat capacity and lack of active on / off control may accelerate heat loss in low-temperature environments.

[0004] In view of the above problems, there is an urgent need to design a novel thermal management system based on phase change thermal storage and gravity heat pipes. This system should be able to effectively resist instantaneous thermal shocks under high power density, alleviate overcooling problems in low-temperature environments, and achieve active, efficient, and passive thermal management in confined spaces. Such a system will help maintain the temperature uniformity of the equipment, ensuring that it always operates within a suitable temperature range, thereby significantly improving the reliability of the equipment. Utility Model Content

[0005] In view of this, in order to solve the problems of instantaneous thermal shock, excessively cold low-temperature environment, difficulty in achieving passive thermal management in confined spaces, and low heat exchange efficiency that affect the applicability of existing thermal management equipment, this utility model provides a dynamic thermal management module and thermal management system based on phase change thermal storage and gravity heat pipe.

[0006] To achieve the above objectives, this utility model provides the following technical solution:

[0007] A dynamic thermal management module based on phase change heat storage and gravity heat pipes includes, from bottom to top, an integrally formed heat source box, a phase change heat storage box, and a heat dissipation box. A heat source is housed within the heat source box. The phase change heat storage box is positioned above the heat source box and includes a hollow, narrow-at-the-top, wide-at-the-bottom phase change material block and a gravity heat pipe inserted within the phase change material block. The phase change material block encapsulates a phase change material with a high coefficient of thermal expansion. When the phase change material is solid, a gap exists between the interface of the phase change material within the phase change material block and the bottom of the evaporation section of the gravity heat pipe. When the phase change material is in a solid-liquid coexistence state, a portion of the phase change material within the phase change material block wraps around the bottom of the evaporation section of the gravity heat pipe. When the phase change material is liquid, the entire phase change material within the phase change material block wraps around the bottom of the evaporation section of the gravity heat pipe.

[0008] Furthermore, the area between the phase change material irregular block, the gravity heat pipe and the phase change heat storage box is a vacuum insulation layer.

[0009] Furthermore, the gravity heat pipe condenser section is provided with several fins protruding from the condenser section. Each fin is arranged in a ring around the cross-section of the condenser section to form a finned condenser placed inside the heat dissipation box.

[0010] Furthermore, the heat source is an electronic device (chip, IGBT module, etc.) that directly heats a phase change material with a high coefficient of thermal expansion, a power battery that facilitates energy storage, or a building material that facilitates energy conservation in buildings, used for dynamic thermal management.

[0011] Furthermore, the high expansion coefficient phase change material is a single or composite phase change material of paraffin, lauric acid, and fatty acids, and is mixed with nanoparticles and expanded graphite-based materials to enhance thermal conductivity.

[0012] Furthermore, the high expansion coefficient phase change material is a tiered arrangement of phase change materials with different melting points, such as paraffin, lauric acid, and fatty acids.

[0013] Furthermore, the cross-section of the phase change material irregular block has a trapezoidal or semi-circular shape, which is narrower at the top and wider at the bottom.

[0014] Furthermore, the finned condenser is an air-cooled type or a finned condenser wrapped with a shaped composite phase change material.

[0015] A dynamic thermal management system based on phase change thermal storage and gravity heat pipe includes the aforementioned dynamic thermal management module based on phase change thermal storage and gravity heat pipe.

[0016] The beneficial effects of this utility model are as follows:

[0017] 1. The dynamic thermal management module based on phase change heat storage and gravity heat pipe disclosed in this utility model utilizes the high latent heat and volume change characteristics of phase change materials with high expansion coefficients, combined with the large equivalent thermal conductivity of gravity heat pipes, to achieve dynamic thermal management, effectively resisting instantaneous thermal shock under high power density and alleviating the overcooling problem of equipment in low-temperature environments; by regulating the volume change of phase change materials and their contact and separation with the evaporation section of gravity heat pipes, passive switching of the heat transfer path and the working mode of the thermal management module is achieved, requiring no external energy or control, reducing energy consumption, and can quickly switch the working mode according to the temperature changes of the heat source in extreme environments and dynamic operating conditions, to dissipate heat or keep the heat source warm, and maintain the equipment working within a suitable temperature range.

[0018] 2. The dynamic thermal management module based on phase change heat storage and gravity heat pipe disclosed in this utility model has a compact design that can be arranged in an array, which greatly improves the temperature uniformity of the heat source and effectively enhances the reliability and service life of the equipment. It is low in cost and simple in structure, without the need for a complex control system or additional moving parts, which reduces the failure rate and maintenance costs. It is small in size and highly integrated, and can be customized according to the heat source. Furthermore, the presence of phase change material increases the effective heat capacity, which can better maintain the equipment temperature.

[0019] 3. The dynamic thermal management module based on phase change heat storage and gravity heat pipe disclosed in this utility model, compared to a single heat pipe or phase change material thermal management module, fully utilizes the high thermal conductivity of the gravity heat pipe and the high latent heat and volume change characteristics of the phase change material to achieve passive switching thermal management capabilities. This effectively avoids the overheating of the phase change material and the problem of the heat pipe not being able to shut down automatically in low-temperature environments. Furthermore, phase change materials with different melting points can be cascaded in the evaporation section of the heat pipe, separated by flexible partitions, increasing the temperature difference between the heat pipe and the phase change material and increasing the heat exchange rate. Therefore, active, efficient, and passive thermal management can be achieved even in confined space environments, making it suitable for critical fields such as energy storage, electronic communications, and aerospace.

[0020] 4. In the dynamic thermal management module based on phase change heat storage and gravity heat pipe disclosed in this utility model, the cross-section of the irregularly shaped phase change material block has a lower end dimension larger than the upper end dimension. Compared with a uniform size or a structure that is wider at the top and narrower at the bottom, this can increase the height difference before and after the phase change material's volume expansion and contraction. Thus, when the volume of the phase change material changes, the difference in the contact area between the evaporation section of the gravity heat pipe and the phase change material is greater, thereby achieving a greater adjustment effect in heat transfer capacity.

[0021] Other advantages, objectives, and features of this invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination and study, or may be learned from practice of this invention. The objectives and other advantages of this invention can be realized and obtained through the following description. Attached Figure Description

[0022] To make the objectives, technical solutions, and advantages of this utility model clearer, the preferred embodiments of this utility model will be described in detail below with reference to the accompanying drawings, wherein:

[0023] Figure 1 This is a schematic diagram illustrating the interaction between the high expansion coefficient phase change material and the gravity heat pipe under different heat exchange modes of this invention. Figure 1 (a) is a diagram showing the interaction between the phase change material and the gravity heat pipe in heat preservation mode / low heat transfer mode. Figure 1 (b) is a diagram showing the interaction between the phase change material and the gravity heat pipe under the medium heat exchange mode. Figure 1 (c) is a diagram showing the interaction between the phase change material and the gravity heat pipe under high heat transfer mode;

[0024] Figure 2 (a) is a graph showing the change in heat exchange capacity of the thermal management module of this utility model with the temperature of the heat source, wherein Figure 2 (b) is a graph showing the change in the contact state between the phase change material and the gravity heat pipe in the thermal management module as a function of the heat source power.

[0025] Figure labels: 1. Heat source, 2. Phase change material with high expansion coefficient, 3. Phase change material irregular block, 4. Gravity heat pipe, 5. Vacuum insulation layer, 6. Finned condenser, 7. Heat dissipation box. Detailed Implementation

[0026] The following specific examples illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification. This utility model can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this utility model.

[0027] The dynamic thermal management module based on phase change thermal storage and gravity heat pipes includes, from bottom to top, an integrally formed heat source box, a phase change thermal storage box, and a heat dissipation box. The heat source box contains a heat source 1, which is an electronic device (chip, IGBT module, etc.) that directly heats the high expansion coefficient phase change material 2, a power battery that facilitates energy storage, and building materials that facilitate building energy conservation, for dynamic thermal management.

[0028] The phase change thermal storage box is positioned above the heat source box. The connection between the phase change thermal storage box and the heat source box is separated by a partition to prevent the high-expansion-coefficient phase change material 2 in the phase change thermal storage box from melting and seeping into the heat source box. The partition is made of thermally conductive silicone grease, which reduces the contact thermal resistance between the heat source 1 and the high-expansion-coefficient phase change material 2.

[0029] The phase change thermal storage box includes a hollow, narrow-at-the-top, wide-at-the-bottom, phase change material (PCM) shaped block 3 and a gravity heat pipe 4 inserted inside the PCM shaped block 3. The upper surface of the PCM shaped block 3 has through holes. The gravity heat pipe 4 is partially inserted into the PCM shaped block 3 and then welded to it to prevent the high-expansion-coefficient PCM 2 from melting and overflowing from the PCM shaped block 3. The high-expansion-coefficient PCM 2 is encapsulated inside the PCM shaped block 3. When the high-expansion-coefficient PCM 2 is solid, there is a gap between the interface of the high-expansion-coefficient PCM 2 inside the PCM shaped block 3 and the bottom of the evaporation section of the gravity heat pipe 4. When the high-expansion-coefficient PCM 2 is in a solid-liquid coexistence state, part of the high-expansion-coefficient PCM 2 inside the PCM shaped block 3 wraps around the bottom of the evaporation section of the gravity heat pipe 4. When the high-expansion-coefficient PCM 2 is liquid, the entire high-expansion-coefficient PCM 2 inside the PCM shaped block 3 wraps around the bottom of the evaporation section of the gravity heat pipe 4. The high expansion coefficient phase change material 2 is a single or composite phase change material with a high expansion coefficient, such as paraffin, lauric acid, or fatty acids, and is mixed with nanoparticles, expanded graphite, and other materials to enhance thermal conductivity. The high expansion coefficient phase change material 2 can be composed of multiple phase change materials (paraffin, lauric acid, fatty acids) with different melting points arranged in a stepped manner.

[0030] The phase change material irregular block has a cross-section where the lower end dimension is larger than the upper end dimension, such as trapezoidal or semi-circular.

[0031] The area between the phase change material shaped block 3, the gravity heat pipe 4, and the phase change heat storage box is a vacuum insulation layer 5. The gravity heat pipe 4 is also welded and sealed to the top of the phase change heat storage box. The condensing section of the gravity heat pipe 4 has several fins protruding from the condensing section. Each fin is arranged in a ring around the cross-section of the condensing section to form a finned condenser 6, which is placed inside the heat dissipation box 7. The finned condenser 6 is an air-cooled type or a finned condenser wrapped with a shaped composite phase change material.

[0032] This dynamic thermal management module, based on phase change thermal storage and a gravity heat pipe, operates in a heat preservation mode when heat source 1 is not in operation. The high-expansion-coefficient phase change material 2 is solid and does not directly contact the bottom of the evaporation section of the gravity heat pipe 4. Figure 1As shown in (a). When heat source 1 operates at low power, some phase change material undergoes a solid-liquid phase change. At this time, the equipment temperature can be maintained solely by the phase change material. The high expansion coefficient phase change material 2 still does not directly contact the bottom of the evaporation section of gravity heat pipe 4. The thermal management module is in low heat exchange mode at this time to prevent gravity heat pipe 4 from rapidly drawing away heat in the low-temperature environment. The equipment temperature is below the optimal temperature range, such as... Figure 1 As shown in (a), when the power of heat source 1 further increases, more solid-liquid phase change material undergoes phase change. At this time, the high expansion coefficient phase change material 2 comes into contact with the evaporation section of gravity heat pipe 4. Gravity heat pipe 4 rapidly transfers heat to finned condenser 6 and, together with the phase change material, controls the temperature of the equipment. The thermal management module is in medium heat exchange mode at this time, as shown in (a). Figure 1 As shown in (b). When the heat source power reaches its maximum, the high expansion coefficient phase change material 2 completely melts and undergoes volume expansion. With the help of the special structure where the lower end of the phase change material block 3 is larger than its upper end, it comes into complete contact with the evaporation section of the gravity heat pipe 4. At this time, the thermal management module is in high heat transfer mode, as shown in (b). Figure 1 As shown in (c).

[0033] The heat exchange capacity of the thermal management module described in this utility model varies with the temperature of the heat source as follows: Figure 2 As shown in (a), when the temperature of heat source 1 is below the freezing point of the high expansion coefficient phase change material 2, the thermal management module is in heat preservation mode to prevent the temperature of heat source 1 from falling below the optimal temperature range. When the temperature of heat source 1 exceeds the freezing point but is below the melting point, the phase change material is in a paste state, utilizing some latent heat for heat management, and the thermal management module is in low heat transfer mode. When the heat source temperature rises further, the high expansion coefficient phase change material 2 melts further, expanding in volume and partially contacting the evaporation section of the gravity heat pipe 4. The thermal management module utilizes the latent heat of phase change and the high thermal conductivity of the heat pipe for heat dissipation, and is in medium heat transfer mode. When the temperature exceeds the melting temperature, the high expansion coefficient phase change material 2 completely envelops the evaporation section of the gravity heat pipe 4, maximizing the heat transfer area, and the thermal management module is in high heat transfer mode. The contact state between the high expansion coefficient phase change material 2 and the gravity heat pipe 4 changes with the heat source power as follows: Figure 2 As shown in (b), its variation curve is similar to... Figure 2 (a) Similarly, there exists a critical power. At this power, the high-expansion-coefficient phase change material 2 begins to contact the evaporation section of the gravity heat pipe 4. Exceeding this power, the rate of change of the contact height between the high-expansion-coefficient phase change material 2 in the phase change material shaped block 3 and the gravity heat pipe 4 gradually increases, preventing overheating of the phase change material and the heat source.

[0034] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of this utility model and are not intended to limit it. Although this utility model has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solution of this utility model without departing from the spirit and scope of this technical solution, and all such modifications or substitutions should be covered within the scope of the claims of this utility model.

Claims

1. A dynamic thermal management module based on phase change thermal storage and gravity heat pipes, characterized by, From bottom to top, it includes an integrally formed heat source box, a phase change heat storage box, and a heat dissipation box. The heat source box contains a heat source (1). The phase change heat storage box is located above the heat source box and includes a hollow phase change material shaped block (3) that is narrow at the top and wide at the bottom, and a gravity heat pipe (4) inserted inside the phase change material shaped block (3). The phase change material shaped block (3) contains a high expansion coefficient phase change material (2). When the high expansion coefficient phase change material (2) is in a solid state, the phase change material shaped block... There is a gap between the interface of the high expansion coefficient phase change material (2) in block (3) and the bottom of the evaporation section of gravity heat pipe (4). When the high expansion coefficient phase change material (2) is in a solid-liquid coexistence state, the high expansion coefficient phase change material (2) in the phase change material block (3) partially wraps the bottom of the evaporation section of gravity heat pipe (4). When the high expansion coefficient phase change material (2) is in a liquid state, the high expansion coefficient phase change material (2) in the phase change material block (3) completely wraps the bottom of the evaporation section of gravity heat pipe (4).

2. The phase change material based and gravity assisted heat pipe based dynamic thermal management module of claim 1, wherein, The area between the phase change material shaped block (3), the gravity heat pipe (4) and the phase change heat storage box is a vacuum insulation layer (5).

3. The dynamic thermal management module based on phase change thermal storage and gravity heat pipe as described in claim 1, characterized in that, The gravity heat pipe (4) has several fins protruding from the condensing section outside. Each fin is arranged in a ring around the cross-section of the condensing section to form a finned condenser (6) placed inside the heat dissipation box (7).

4. The phase change material and gravity assisted heat pipe based dynamic thermal management module of claim 1, wherein, The heat source (1) is an electronic device, power battery, or building material that directly heats the high expansion coefficient phase change material (2) for its dynamic thermal management.

5. The phase change material and gravity assisted heat pipe based dynamic thermal management module of claim 1, wherein, The phase change material shaped block (3) has a trapezoidal or semi-circular cross-section that is narrow at the top and wide at the bottom.

6. The phase change material and gravity assisted heat pipe based dynamic thermal management module of claim 3, wherein, The finned condenser (6) is an air-cooled finned condenser or a finned condenser wrapped with a shaped composite phase change material.

7. A dynamic thermal management system based on phase change thermal storage and gravity heat pipes, characterized in that, It includes the dynamic thermal management module based on phase change thermal storage and gravity heat pipe as described in any one of claims 1 to 6.

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