Multi-working-medium cascade low-temperature gravity assisted heat pipe cooling device

Abstract

The invention relates to the technical field of low-temperature heat pipes, and provides a multi-working-medium cascade low-temperature gravity heat pipe cooling device which comprises multiple sets of low-temperature gravity heat pipes arranged in parallel, each set of low-temperature gravity heat pipe is provided with an independent air inlet liquid filling system, and the multiple sets of low-temperature gravity heat pipes share a condensation section and an evaporation section. Working media of different two-phase temperature zones are adopted in the multiple sets of low-temperature gravity assisted heat pipes, the condensation section is used for making contact with a cold source, and the evaporation section is used for making contact with a cooled part. According to the multi-working-medium cascade low-temperature gravity assisted heat pipe cooling device, effective heat transfer of a wide temperature area is achieved in a parallel connection mode, so that each low-temperature gravity assisted heat pipe operates at the optimal working temperature of the low-temperature gravity assisted heat pipe, and the continuous cooling effect from the room temperature area to the liquid nitrogen temperature area is achieved; and besides, the applicable temperature area of the same heat pipe system is greatly widened, additional components such as a wick and other heat exchangers do not need to be introduced, the stability and flexibility of the system are improved, and different cooling requirements can be met.

Description

Technical Field

[0001] The invention relates to the technical field of low-temperature heat pipes, and in particular to a multi-working medium cascade low-temperature gravity heat pipe cooling device. Background Art

[0002] Low temperature heat pipe technology is a highly efficient heat transfer technology. Gravity heat pipe, as a form of heat pipe, is also called two-phase closed thermosyphon heat pipe. It consists of three parts: evaporation section, insulation section and condensation section. There is no liquid absorption core inside, and the liquid relies on gravity to return. The working principle of gravity heat pipe is to use the working fluid to absorb heat and vaporize in the evaporation section, and the steam flows to the condensation section under the action of pressure difference to release heat and liquefy, and the liquid then flows back to the evaporation section along the inner wall by gravity to achieve heat transfer.

[0003] In the prior art, due to its unique two-phase heat transfer mechanism, the heat transfer capacity of heat pipes is better than that of high thermal conductivity metal copper with the same cross-sectional area. However, the single working fluid limits the application of low-temperature heat pipes in a wide temperature range, and a single low-temperature heat pipe cannot be used to achieve pre-cooling in a wide temperature range. Summary of the invention

[0004] The present invention provides a multi-working medium cascade low-temperature gravity heat pipe cooling device, which is used to solve the defect that a single low-temperature heat pipe in the prior art cannot achieve pre-cooling in a wide temperature range, and realize effective heat transfer in a wide temperature range in different temperature intervals.

[0005] The present invention provides a multi-working medium cascade low-temperature gravity heat pipe cooling device, comprising: Multiple groups of low-temperature gravity heat pipes are arranged in parallel, each group of the low-temperature gravity heat pipes has an independent air intake and liquid filling system, the multiple groups of low-temperature gravity heat pipes share a condensation section and an evaporation section, and the multiple groups of low-temperature gravity heat pipes use working fluids in different two-phase temperature zones, the condensation section is used to contact with a cold source, and the evaporation section is used to contact with a cooled component.

[0006] According to a multi-working medium cascade low-temperature gravity heat pipe cooling device provided by the present invention, the condensation section includes a copper condensation plate.

[0007] According to a multi-working medium cascade low-temperature gravity heat pipe cooling device provided by the present invention, the evaporation section includes a copper evaporation plate.

[0008] A multi-working fluid cascade low-temperature gravity heat pipe cooling device provided by the present invention comprises three groups of low-temperature gravity heat pipes connected in parallel, wherein the three groups of low-temperature gravity heat pipes respectively use R134a working fluid, liquid nitrogen working fluid and liquid neon working fluid.

[0009] According to a multi-working medium cascade low-temperature gravity heat pipe cooling device provided by the present invention, the low-temperature gravity heat pipe adopts R22 or R134a as the working medium for pre-cooling in the temperature range of 250K-150K.

[0010] According to a multi-working medium cascade low-temperature gravity heat pipe cooling device provided by the present invention, the low-temperature gravity heat pipe uses nitrogen or argon as a pre-cooling working medium in a temperature range of 150K-80K.

[0011] According to a multi-working medium cascade low-temperature gravity heat pipe cooling device provided by the present invention, each of the low-temperature gravity heat pipes comprises: A first pipe section, integrally connected to the condensing section; A second pipe section is arranged at an end of the first pipe section facing away from the condensing section; The third pipe section has one end disposed at one end of the second pipe section facing away from the first pipe section, and the other end of the third pipe section is integrally connected to the evaporation section.

[0012] According to a multi-working medium cascade low-temperature gravity heat pipe cooling device provided by the present invention, the first pipe section is a copper pipe; the second pipe section is a stainless steel pipe; and the third pipe section is a copper pipe.

[0013] According to a multi-working medium cascade low-temperature gravity heat pipe cooling device provided by the present invention, the plurality of low-temperature gravity heat pipes are all round pipes.

[0014] According to a multi-working medium cascade low-temperature gravity heat pipe cooling device provided by the present invention, the diameters of the plurality of low-temperature gravity heat pipes are equal or unequal.

[0015] The multi-working medium cascade low-temperature gravity heat pipe cooling device provided by the present invention comprises a plurality of groups of low-temperature gravity heat pipes arranged in parallel, each group of low-temperature gravity heat pipes having an independent air intake and liquid filling system, the plurality of groups of low-temperature gravity heat pipes sharing a condensation section and an evaporation section, and the plurality of groups of low-temperature gravity heat pipes using working medium in different two-phase temperature zones, the condensation section being used for contacting with a cold source, and the evaporation section being used for contacting with a cooling element; utilizing the optimal heat transfer characteristics of different working mediums within a specific range, effective heat transfer in a wide temperature zone is achieved in a parallel manner, so that each low-temperature gravity heat pipe operates at its optimal operating temperature, thereby achieving a continuous cooling effect from room temperature to a liquid nitrogen temperature zone.

[0016] The multi-media cascade low-temperature gravity heat pipe cooling device provided by the present invention greatly broadens the applicable temperature range of the same heat pipe system, and does not require the introduction of additional components such as liquid absorption cores, other heat exchangers, etc., thereby improving the stability and flexibility of the system and being able to adapt to different cooling needs. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 It is a structural schematic diagram of the multi-working medium cascade low-temperature gravity heat pipe cooling device provided by the present invention.

[0019] Figure 2 It is a cross-sectional view of the multi-working medium cascade low-temperature gravity heat pipe cooling device provided by the present invention.

[0020] Reference numerals: 1. Low-temperature gravity heat pipe; 2. Condensation section; 3. Evaporation section; 11. First pipe section; 12. Second pipe section; 13. Third pipe section. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] In the description of the embodiments of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limitations on the embodiments of the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0023] In the prior art, heat pipes have a better heat transfer capacity than high thermal conductivity copper metal with the same cross-sectional area due to their unique two-phase heat transfer mechanism. However, the single working fluid limits the application of low-temperature heat pipes in a wide temperature range, and it is impossible to use a single low-temperature heat pipe to achieve pre-cooling in a wide temperature range. When cooling an object with a relatively high thermal mass, such as a superconducting magnet, from room temperature to the temperature range of liquid nitrogen or liquid helium, there is no single working fluid that covers the two-phase region from room temperature to extremely low temperatures, so it is impossible to use a single low-temperature heat pipe to achieve pre-cooling in a wide temperature range.

[0024] In view of the above technical problems, the following Figure 1-Figure 2 , an embodiment of the present invention provides a multi-working fluid cascade low-temperature gravity heat pipe cooling device.

[0025] A multi-working fluid cascade low-temperature gravity heat pipe cooling device provided by an embodiment of the present invention includes multiple groups of low-temperature gravity heat pipes 1 arranged in parallel, each group of low-temperature gravity heat pipes 1 has an independent air intake and liquid filling system, allowing each group of low-temperature gravity heat pipes 1 to be accurately filled with working fluid and pressure controlled. Multiple groups of low-temperature gravity heat pipes 1 share a condensation section 2 and an evaporation section 3, which can ensure efficient heat exchange and structural stability. Using working fluids in different two-phase temperature zones in multiple groups of low-temperature gravity heat pipes 1 can allow the system to use the most suitable working fluid in different temperature ranges, thereby improving cooling efficiency and adaptability. The condensation section 2 is used to contact with the cold source, and the condensation section 2 condenses the working fluid in the heat pipe into a liquid through heat exchange. The evaporation section 3 is used to contact with the cooled part, and the working fluid absorbs heat and vaporizes in the evaporation section 3, thereby achieving a cooling effect.

[0026] The cold source is the starting point for providing cooling, usually the source of refrigerant or cooling liquid. The condensation section 2 is in contact with the cold source. The condensation section 2 is the condensation part of the heat pipe. In the condensation section 2, the steam rising from the evaporation section 3 is cooled and liquefied, releasing heat. The low-temperature gravity heat pipe 1 contains a working fluid, which absorbs heat in the evaporation section 3 and is converted into steam.

[0027] like Figure 1 and Figure 2 As shown, the multi-working fluid cascade low-temperature gravity heat pipe cooling device provided by the present invention utilizes the optimal heat transfer characteristics of different working fluids within a specific range, and realizes effective heat transfer in a wide temperature range by parallel connection, so that each low-temperature gravity heat pipe operates at its optimal working temperature, thereby achieving a continuous cooling effect from room temperature to liquid nitrogen temperature zone, covering a wider temperature range.

[0028] The independent air intake and liquid filling system makes the working fluid filling and pressure control of each group of low-temperature gravity heat pipes 1 more precise, which helps to optimize the heat exchange efficiency and system stability. The shared condensation section 2 and evaporation section 3 simplify the structure while ensuring the high efficiency of heat exchange.

[0029] The multi-media cascade low-temperature gravity heat pipe cooling device provided by the present invention greatly broadens the applicable temperature range of the same heat pipe system, and does not require the introduction of additional components such as liquid absorption cores, other heat exchangers, etc., thereby improving the stability and flexibility of the system and being able to adapt to different cooling needs.

[0030] The multi-media cascade low-temperature gravity heat pipe cooling device provided by the present invention significantly improves the energy recovery efficiency and overall efficiency of the system by optimizing the distribution of inter-stage heat exchangers. It not only improves the cooling capacity, but also reduces the energy loss of the system; it can achieve the maximum cooling efficiency and cooling temperature difference through multi-stage optimization, not only achieving the same cooling temperature difference, but also greatly improving the cooling efficiency and energy saving effect.

[0031] like Figure 1 and Figure 2As shown, in a feasible embodiment of the present invention, the condensation section 2 includes a copper condensation plate, and the evaporation section 3 includes a copper evaporation plate. The copper condensation plate can quickly transfer the cold energy provided by the cold source to the working medium in the low-temperature gravity heat pipe 1 to condense it. The copper evaporation plate can efficiently absorb heat from the cooled part and transfer it to the working medium in the low-temperature gravity heat pipe 1 to evaporate it.

[0032] It should be noted that the high thermal conductivity of copper helps to improve the heat exchange efficiency of the heat pipe. The thermal conductivity of copper is much higher than that of other commonly used metals. Under the same temperature gradient, copper can transfer more heat, which helps to speed up the condensation and evaporation process, thereby improving the heat exchange efficiency of the entire heat pipe cooling system. The use of copper material can reduce the thermal resistance in the heat exchange process, allowing heat to be transferred more smoothly between the condensation section 2 and the evaporation section 3, which helps to maintain the stable operation of the system and reduce energy loss.

[0033] Therefore, using copper material to manufacture the condensing section 2 and the evaporating section 3 is an effective choice, which can not only improve the heat exchange efficiency of the heat pipe, but also help to enhance the structural stability and reliability of the system.

[0034] More specifically, in one embodiment of the present invention, three groups of low-temperature gravity heat pipes 1 are connected in parallel, and the three groups of low-temperature gravity heat pipes 1 use R134a (tetrachloroethane) working fluid, liquid nitrogen working fluid and liquid neon working fluid respectively.

[0035] Among them, R134a is a commonly used low-temperature refrigerant with good thermophysical properties and chemical stability. It is suitable for heat exchange in medium and low temperature areas and can provide a stable cooling effect.

[0036] Liquid nitrogen has a very low boiling point (-196°C) and is suitable for heat exchange in cryogenic areas. When liquid nitrogen is used as a working fluid, it can provide extremely high cooling efficiency and is particularly suitable for occasions that require extremely low temperatures.

[0037] Liquid neon has a boiling point (-246°C) slightly higher than liquid nitrogen and is also a cryogenic fluid. Liquid neon may have better performance than liquid nitrogen in certain specific applications, such as in some low-temperature physics experiments or superconducting technology.

[0038] In the above embodiments, by adopting working fluids in different two-phase temperature zones (R134, liquid nitrogen, liquid neon), the cooling device in this embodiment can adapt to cooling requirements in different temperature ranges, such as low-temperature physics experiments, superconducting technology, medical equipment, etc.

[0039] Furthermore, in the temperature range of 250K-150K, R22 (chlorodifluoromethane) or R134a (tetrachloroethane) is selected as the main pre-cooling working fluid. In the temperature range of 150K-80K, liquid nitrogen or liquid argon is selected as the main pre-cooling working fluid to achieve the effect of cooling high thermal mass objects such as superconducting magnets from room temperature to the liquid nitrogen temperature range.

[0040] In the above embodiments, the cascade cooling system connects cryogenic gravity heat pipes of different temperatures in parallel so that each cryogenic gravity heat pipe operates at its optimal operating temperature, thereby achieving a continuous cooling effect from room temperature to liquid nitrogen temperature zone, and is therefore called cascade cooling.

[0041] This embodiment is particularly suitable for applications that require efficient thermal management in different temperature ranges, such as in the fields of spacecraft thermal control and superconducting magnet cooling. The cascade cooling system can significantly reduce the cooling time and improve the cooling efficiency.

[0042] The cascade cooling system is capable of achieving refrigeration temperatures as low as -170°C, significantly expanding the refrigeration temperature range of conventional systems. This capability gives the cascade cooling system a significant advantage in applications requiring extremely low temperatures.

[0043] like Figure 1 and Figure 2 As shown, in one embodiment of the present invention, each low-temperature gravity heat pipe 1 includes a first pipe section 11 , a second pipe section 12 and a third pipe section 13 .

[0044] The first pipe section 11 is integrally connected to the condensing section 2, that is, the first pipe section 11 and the condensing section 2 are both made of copper material. The integrated connection method is crucial to improving the heat transfer efficiency, reducing the energy loss during the heat transfer process, and ensuring the efficient transfer of heat from the condensing section 2 to the first pipe section 11, thereby enhancing the heat transfer efficiency.

[0045] The second pipe section 12 is arranged at the end of the first pipe section 11 facing away from the condensation section 2. The second pipe section 12 needs to be insulated from the outside. Therefore, the material of the second pipe section 12 needs to be selected to prevent heat from being transferred from the inside of the heat pipe to the external environment, thereby maintaining the temperature gradient of the working medium inside the heat pipe.

[0046] One end of the third pipe segment 13 is arranged at an end of the second pipe segment 12 facing away from the first pipe segment 11, and the other end of the third pipe segment 13 is integrally connected to the evaporation segment 3. Similar to the first pipe segment 11, the third pipe segment 13 ensures that heat can be transferred from the evaporation segment 3 to the working medium inside the heat pipe, thereby enhancing the heat transfer efficiency.

[0047] Therefore, this embodiment of the present invention not only achieves efficient heat transfer inside the heat pipe through the arrangement of the first pipe segment 11, the second pipe segment 12 and the third pipe segment 13, but also maintains the working efficiency and stability of the heat pipe through insulation treatment.

[0048] More specifically, the first pipe section 11 is a copper pipe; the second pipe section 12 is a stainless steel pipe; and the third pipe section 13 is a copper pipe. The first pipe section 11 and the third pipe section 13 are copper pipes, which can maximize the efficiency of heat transfer from the condensation section 2 to the inside of the low-temperature gravity heat pipe 1. The stainless steel pipe has good corrosion resistance and mechanical strength. The second pipe section 12 is an insulating part in the heat pipe. The stainless steel pipe can reduce heat loss through appropriate insulation measures while maintaining structural strength.

[0049] The first pipe section 11 is welded to the second pipe section 12, and the third pipe section 13 is welded to the second pipe section 12. Welding is a reliable connection method that can provide good sealing and structural strength. Through welding, a tight connection between the first pipe section 11, the second pipe section 12 and the third pipe section 13 can be ensured, heat loss at the connection can be reduced, and the overall heat transfer efficiency of the heat pipe can be improved.

[0050] Therefore, the low-temperature gravity heat pipe 1 of the present invention optimizes the structural strength, heat transfer efficiency and corrosion resistance by using pipe sections of different materials and welding connection methods. The first pipe section 11 and the third pipe section 13 use copper pipes to improve the heat transfer efficiency, and the second pipe section 12 uses stainless steel pipes to provide corrosion resistance and mechanical strength. At the same time, the three pipe sections are connected by welding to ensure the overall performance and reliability of the heat pipe. This design has significant advantages in occasions where efficient heat transfer and long-term stable operation are required.

[0051] In a feasible embodiment of the present invention, the plurality of low-temperature gravity heat pipes 1 are all round pipes; round pipe-shaped heat pipes are convenient in manufacturing, installation and maintenance, and also help to improve heat transfer efficiency. Round pipe-shaped heat pipes can evenly distribute heat, reduce heat accumulation on the pipe wall, and thus improve heat exchange efficiency.

[0052] Furthermore, the diameters of the multiple cryogenic gravity heat pipes 1 may be equal or unequal. If the diameters are equal, the cryogenic gravity heat pipes 1 will be consistent in terms of heat transfer performance, structural strength, and material usage, which helps to simplify the design and manufacturing process. If the diameters are unequal, heat pipes of different diameters may be selected based on specific application requirements and heat transfer requirements. For example, in areas where higher heat transfer efficiency is required, heat pipes with larger diameters may be selected to increase the heat exchange area; while in areas where space is limited or material usage needs to be reduced, heat pipes with smaller diameters may be selected.

[0053] This embodiment provides greater design flexibility by allowing the diameters of the cryogenic gravity heat pipes 1 to be equal or unequal, which helps to meet the specific needs and restrictions in different application scenarios. The cryogenic gravity heat pipe cooling device in this embodiment is suitable for a variety of application scenarios, including but not limited to low-temperature physics experiments, superconducting technology, medical equipment, aerospace and other fields. By adjusting the diameter and number of heat pipes, the heat transfer efficiency and structural strength of the system can be optimized to meet the needs of different applications.

[0054] In summary, the multi-working fluid cascade low-temperature heat pipe cooling device provided in the embodiment of the present invention connects multiple low-temperature gravity heat pipes with different working fluids in parallel, and uses the most suitable working fluid in different temperature ranges, thereby achieving a continuous cooling effect from room temperature to extremely low temperature.

[0055] In the description of the embodiments of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific circumstances.

[0056] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "mode", "specific mode", or "some modes" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or mode are included in at least one embodiment or mode of the embodiment of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or mode. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or modes in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or modes described in this specification and the features of the different embodiments or modes, without contradiction.

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A multi-working medium cascade low-temperature gravity heat pipe cooling device, characterized in that: include: A plurality of groups of low-temperature gravity heat pipes (1) are arranged in parallel, each group of the low-temperature gravity heat pipes (1) having an independent air intake and liquid filling system, the plurality of groups of low-temperature gravity heat pipes (1) share a condensation section (2) and an evaporation section (3), and the plurality of groups of low-temperature gravity heat pipes (1) use working fluids in different two-phase temperature zones, the condensation section (2) is used to contact a cold source, and the evaporation section (3) is used to contact a cooled component.

2. The multi-working medium cascade low-temperature gravity heat pipe cooling device according to claim 1, characterized in that: The condensation section (2) comprises a copper condensation plate.

3. The multi-working medium cascade low-temperature gravity heat pipe cooling device according to claim 1, characterized in that: The evaporation section (3) comprises a copper evaporation plate.

4. The multi-working medium cascade low-temperature gravity heat pipe cooling device according to claim 1, characterized in that: The invention comprises three groups of low-temperature gravity heat pipes (1) connected in parallel, wherein the three groups of low-temperature gravity heat pipes (1) respectively use R134a working fluid, liquid nitrogen working fluid and liquid neon working fluid.

5. The multi-media cascade low-temperature gravity heat pipe cooling device according to any one of claims 1 to 3, characterized in that: The low-temperature gravity heat pipe (1) uses R22 or R134a as a pre-cooling working fluid in a temperature range of 250K-150K.

6. The multi-media cascade low-temperature gravity heat pipe cooling device according to any one of claims 1 to 3, characterized in that: The low-temperature gravity heat pipe (1) uses nitrogen or argon as a pre-cooling working fluid in a temperature range of 150K-80K.

7. The multi-media cascade low-temperature gravity heat pipe cooling device according to claim 1, characterized in that: Each of the low-temperature gravity heat pipes (1) comprises: A first pipe section (11) is integrally connected to the condensation section (2); A second pipe section (12) is arranged at an end of the first pipe section (11) facing away from the condensation section (2); A third pipe section (13) has one end arranged at an end of the second pipe section (12) facing away from the first pipe section (11), and the other end of the third pipe section (13) is integrally connected to the evaporation section (3).

8. The multi-media cascade low-temperature gravity heat pipe cooling device according to claim 7, characterized in that: The first pipe section (11) is a copper pipe; the second pipe section (12) is a stainless steel pipe; and the third pipe section (13) is a copper pipe.

9. The multi-media cascade low-temperature gravity heat pipe cooling device according to claim 1, characterized in that: The plurality of low-temperature gravity heat pipes (1) are all round pipes.

10. The multi-working medium cascade low-temperature gravity heat pipe cooling device according to claim 9, characterized in that: The diameters of the plurality of low-temperature gravity heat pipes (1) are equal or unequal.

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