Coupling heat pipe type low-temperature mechanical refrigerator

Abstract

The utility model discloses a coupling heat pipe type low-temperature mechanical refrigerator which comprises a compressor, an expansion machine, a connecting pipe and a heat pipe system, and the compressor comprises a shell heat exchanger; the expansion machine comprises a hot end heat exchanger; the connecting pipe is arranged between the compressor and the expansion machine and connects the compressor with the expansion machine; a part of the heat pipe system is arranged between the shell heat exchanger and the hot end heat exchanger, a part of the heat pipe system is arranged in the shell heat exchanger, and a part of the heat pipe system is arranged in the hot end heat exchanger. According to the technical scheme, the heat pipe is coupled with the refrigerator shell, heat dissipation of a traditional refrigerator only depending on the hot end of an expansion machine which is small in heat exchange area and large in heat dissipation capacity is converted into heat dissipation of the surface of the compressor shell and the surface of the hot end of the expansion machine together, and the heat exchange area is effectively increased; the problems that small and medium-sized low-temperature mechanical refrigerators are small in heat exchange area, high in heat exchange temperature difference, high in hot end temperature, small in heat exchange amount and the like are solved.

Description

Technical Field

[0001] The utility model relates to the technical field of low-temperature mechanical refrigerators, in particular to a coupled heat pipe type low-temperature mechanical refrigerator. Background Art

[0002] Infrared detectors are the core components of infrared detection, infrared night vision and infrared guidance devices. Cryogenic mechanical refrigerators provide a low-temperature environment for detector chips, which can reduce noise and improve imaging quality. They are the core components of infrared detectors. According to the first law of thermodynamics, the cooling capacity of a refrigerator is equal to the difference between the heat dissipation at the hot end of the refrigerator and the input electrical power. Therefore, increasing the heat dissipation at the hot end of the refrigerator can effectively increase the cooling capacity of the refrigerator. According to the second law of thermodynamics, the relative Carnot efficiency of a refrigerator is related to the temperature of the heat source and the temperature of the cold source. Increasing the heat exchange efficiency between the hot end of the refrigerator and the environment and reducing the heat exchange temperature difference can improve the relative Carnot efficiency of the refrigerator.

[0003] In practical applications, the heat dissipation of the hot end of conventional small and medium-sized Stirling refrigerators and pulse tube refrigerators usually adopts natural convection, and fins are usually added to the outside of the hot end to increase the heat exchange area to increase the heat exchange amount. A small number of small and medium-sized Stirling refrigerators and pulse tube refrigerators also use fan direct blowing or external liquid circuits (such as water) for liquid cooling. Aviation, aerospace and weapon infrared detectors require refrigerators to comply with the SWaP rule, that is, small size (Size), light weight (Weight) and high performance (Performance). However, due to system conditions, conventional small and medium-sized low-temperature refrigerators in practical applications often cannot install radiators with sufficient heat dissipation area at their hot ends, and it is difficult to use forced convection measures such as air cooling. They can only rely on natural convection for heat exchange, which has the disadvantages of small heat exchange area, high heat exchange temperature difference, high hot end temperature and small heat exchange amount, resulting in small cooling capacity and low cooling efficiency of the refrigerator. The method of using fan direct blowing or external liquid circuit to cool the hot end of the refrigerator will increase the size, weight and power consumption of the entire system, seriously limiting its engineering application. Utility Model Content

[0004] The main purpose of the utility model is to provide a coupled heat pipe low-temperature mechanical refrigerator, which aims to solve the shortcomings of the existing Stirling refrigerator and pulse tube refrigerator, such as small heat exchange area, high heat exchange temperature difference, high hot end temperature and small heat exchange amount, which leads to the problem of small cooling capacity and low cooling efficiency of the refrigerator.

[0005] To achieve the above object, the utility model proposes a coupled heat pipe low temperature mechanical refrigerator, comprising:

[0006] a compressor, the compressor comprising a shell heat exchanger;

[0007] an expander, the expander comprising a hot end heat exchanger;

[0008] a connecting pipe, the connecting pipe being provided between the compressor and the expander and connecting the compressor and the expander; and,

[0009] A heat pipe system is partially arranged between the shell heat exchanger and the hot end heat exchanger, partially arranged in the shell heat exchanger, and partially arranged in the hot end heat exchanger.

[0010] Preferably, the heat pipe system comprises a gas section heat pipe pipeline, a condensation section heat pipe pipeline, a liquid section heat pipe pipeline and an evaporation section heat pipe pipeline.

[0011] Preferably, the evaporation section heat pipe circuit is arranged in the hot end heat exchanger.

[0012] Preferably, the condensing section heat pipe circuit is arranged in the shell heat exchanger.

[0013] Preferably, one end of the gas section heat pipe pipeline is connected to the condensing section heat pipe pipeline, and the other end is connected to the evaporating section heat pipe pipeline.

[0014] Preferably, one end of the liquid section heat pipe pipeline is connected to the condensing section heat pipe pipeline, and the other end is connected to the evaporating section heat pipe pipeline.

[0015] Preferably, the cross section of the liquid section heat pipe is circular and its inner wall has a capillary structure.

[0016] Preferably, the condensing section heat pipe pipeline is a channel opened in the compressor casing.

[0017] Preferably, the channel is arranged helically around the compressor casing.

[0018] Compared with the prior art, the beneficial effects of the present invention are:

[0019] (1) The technical solution of the utility model is to couple the heat pipe with the refrigerator casing, thereby converting the heat dissipation of the traditional refrigerator, which only relies on the heat exchange area but large heat dissipation demand of the expander hot end, into heat dissipation by the compressor casing surface and the expander hot end surface together, thereby effectively increasing the heat exchange area, solving the problems of small heat exchange area, high heat exchange temperature difference, high hot end temperature and small heat exchange amount in practical applications of small and medium-sized low-temperature mechanical refrigerators, and improving the cooling capacity and refrigeration efficiency of the refrigerator.

[0020] (2) The utility model integrates the heat pipe system into a traditional refrigerator, does not require additional heat dissipation equipment, has a compact structure, small size and light weight, and meets the structural requirements of infrared detectors for aviation, aerospace and weapons. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0022] Figure 1 It is a structural schematic diagram of an embodiment of the coupled heat pipe low-temperature mechanical refrigerator of the utility model;

[0023] Figure 2 for Figure 1 Cross-sectional diagram of the heat pipe of the liquid section of the middle refrigerator;

[0024] Figure 3 for Figure 1 Structural diagram of the working principle of the refrigerator.

[0025] Description of Figure Numbers:

[0026] Label name Label name 100 Coupled heat pipe cryogenic mechanical refrigerator 4 Heat pipe system 1 compressor 41 Gas section heat pipe pipeline 11 Shell heat exchanger 42 Condensation section heat pipe 2 Connecting pipe 43 Liquid section heat pipe line 3 Expander 44 Evaporation section heat pipe pipeline 31 Hot end heat exchanger

[0027] The realization of the purpose, functional features and advantages of the utility model will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0029] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back...) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0030] In addition, the descriptions of "first", "second", etc. in the present utility model are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in this field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present utility model.

[0031] In view of the fact that the existing refrigerators are often unable to install radiators with sufficient heat dissipation area, there are disadvantages such as small heat exchange area, high heat exchange temperature difference, high hot end temperature and small heat exchange amount, resulting in the problem of small cooling capacity and low cooling efficiency of the refrigerator, the utility model proposes a coupled heat pipe low-temperature mechanical refrigerator, referring to Figures 1 to 3 , Figure 1 It is a structural schematic diagram of an embodiment of the coupled heat pipe low-temperature mechanical refrigerator of the utility model; Figure 2 for Figure 1 Cross-sectional diagram of the heat pipe of the liquid section of the middle refrigerator; Figure 3 for Figure 1 The working principle of the refrigerator is shown in FIG.

[0032] In the embodiment of the present utility model, Figure 1 As shown, the coupled heat pipe low-temperature mechanical refrigerator 100 includes a compressor 1, an expander 3, a connecting pipe 2 and a heat pipe system 4, wherein the compressor 1 includes a shell heat exchanger 11; the expander 3 includes a hot end heat exchanger 31; the connecting pipe 2 is arranged between the compressor 1 and the expander 3, and connects the compressor 1 with the expander 3; the heat pipe system 4 is partially arranged between the shell heat exchanger 11 and the hot end heat exchanger 31, partially arranged in the shell heat exchanger 11, and partially arranged in the hot end heat exchanger 31.

[0033] The utility model arranges part of the heat pipe system 4 between the shell heat exchanger 11 of the compressor 1 and the hot end heat exchanger 31 of the expander 3 and part of the heat pipe system 4 inside the compressor 1, so as to transfer the heat at the hot end of the expander 3 with a higher temperature but a smaller heat exchange area to the shell of the compressor 1 with a lower temperature but a larger heat exchange area, thereby increasing the heat exchange between the refrigerator and the environment, reducing the hot end temperature of the expander 3, and finally improving the cooling capacity and relative Carnot efficiency of the refrigerator.

[0034] For further information, please refer to Figure 1The coupled heat pipe type low temperature mechanical refrigerator 100 proposed in the utility model is formed by coupling a refrigerator system and a heat pipe system 4. The refrigerator system is composed of a compressor 1, a connecting pipe 2 and an expander 3. The heat pipe system 4 includes a gas section heat pipe pipeline 41, a condensation section heat pipe pipeline 42, a liquid section heat pipe pipeline 43 and an evaporation section heat pipe pipeline 44, and is filled with a certain mass of refrigerant. When the refrigerator is running stably, the temperature of the hot end heat exchanger 31 with a smaller heat exchange area is the highest, usually higher than the ambient temperature by more than 40°C, while the temperature of the compressor 1 shell heat exchanger 11 with a larger heat exchange area is close to the ambient temperature. By coupling the heat pipe system 4 with a multi-section pipeline setting with the refrigerator system, the temperature in the hot end heat exchanger 31 with a smaller heat exchange area is transmitted to the compressor 1 shell with a larger heat exchange area, thereby increasing the heat exchange efficiency.

[0035] Preferably, in one embodiment of the present invention, please refer to Figure 1 , the evaporation section heat pipe pipeline 44 is arranged in the hot end heat exchanger 31, and the evaporation section heat pipe pipeline 44 is coupled with the expander 3 through the hot end heat exchanger 31. For the hot end heat exchanger 31 with a circular radial cross section, the evaporation section heat pipe pipeline 44 is a spiral structure, and its cross section is preferably rectangular, which further increases the heat exchange area. The hot end heat exchanger 31 adopts an inner and outer two-ring split structure. First, a spiral evaporation section heat pipe pipeline 44 is processed on the inner side of the hot end heat exchanger 31, and then the hot end heat exchanger 31 sleeve is put on the outer side. The two are welded at the ends to finally form a hot end heat exchanger 31 with a spiral evaporation section heat pipe pipeline 44 inside; for the hot end heat exchanger 31 with a rectangular radial cross section, 4 holes can be evenly distributed in the X direction, the Y direction and the Z direction to form a cubic structure together. The 12 evaporation section heat pipe pipelines 44 constitute the edges of the cube, and the punching points are welded to keep the internal seal.

[0036] Please refer to Figure 1 Preferably, the condensing section heat pipe pipeline 42 is arranged in the shell heat exchanger 11, and the condensing section heat pipe pipeline 42 is coupled with the compressor 1 through the compressor 1 shell heat exchanger 11. By setting a coupling structure, the heat exchange efficiency between the condensing section heat pipe pipeline 42 and the shell heat exchanger 11 is improved.

[0037] For further information, see Figure 1, one end of the gas section heat pipe pipeline 41 is connected to the condensing section heat pipe pipeline 42, and the other end is connected to the evaporating section heat pipe pipeline 44; similarly, one end of the liquid section heat pipe pipeline 43 is connected to the condensing section heat pipe pipeline 42, and the other end is connected to the evaporating section heat pipe pipeline 44. The gas section heat pipe pipeline 41, the condensing section heat pipe pipeline 42, the liquid section heat pipe pipeline 43 and the evaporating section heat pipe pipeline 44 are connected to each other to form a closed pipeline. When the refrigerator is running stably, the refrigerant in the heat pipe evaporates in the evaporating section heat pipe pipeline 44 and absorbs heat to become gas. The gaseous working medium enters the condensing section heat pipe pipeline 42 along the pipeline counterclockwise to condense and release heat to become liquid. The liquid working medium returns to the evaporating section heat pipe pipeline 44 counterclockwise along the liquid section heat pipe pipeline 43, completing a cycle. After continuous circulation, the heat in the hot end heat exchanger 31 is continuously transferred to the compressor 1 shell heat exchanger 11, and the heat is transferred to the environment through the larger heat exchange area of ​​the compressor 1 shell. The compressor 1 shell heat exchanger 11 can also add fins or use air cooling or water cooling to further enhance the heat dissipation effect.

[0038] In one embodiment of the present invention, please refer to Figure 2 The cross section of the liquid section heat pipe pipeline 43 is circular and its inner wall has a capillary structure. A plurality of thin tubular channel structures are provided from the inner wall of the liquid section heat pipe pipeline 43 to the center. After the gas working medium enters the condensing section heat pipe pipeline 42 along the gas section heat pipe pipeline 41 and becomes liquid, it returns to the evaporating section heat pipe pipeline 44 counterclockwise along the liquid section heat pipe pipeline 43 under the action of the capillary force generated by the capillary structure.

[0039] In one embodiment of the present invention, please refer to Figure 3 The condensing section heat pipe pipeline 42 is a channel opened in the shell of the compressor 1. By setting the condensing section heat pipe pipeline 42 as a channel structure, it is convenient to transport the liquid in the pipeline and facilitate the heat exchange between the liquid in the pipeline and the shell heat exchanger 11 of the compressor 1. Preferably, the channel is spirally arranged around the shell of the compressor 1. The spiral arrangement structure further increases the heat exchange area between the channel and the shell heat exchanger 11, thereby improving the heat exchange efficiency.

[0040] Please refer to Figure 3The following uses the example of a linear Stirling refrigerator to explain the working principle of the refrigerator: When alternating current is passed through the coil, an alternating magnetic field is generated in the outer yoke, the inner yoke and the air gap between the two. The magnetic steel is subjected to axial electromagnetic force in the alternating magnetic field, performs reciprocating linear motion and drives the piston fixed to the magnetic steel to perform periodic compression and expansion processes. The cold storage device, the push piston and the mechanical spring in the cold finger constitute a single-degree-of-freedom small-damping spring oscillator system, which performs axial reciprocating motion under the action of the pressure wave from the connecting pipe 2. The working fluid gas in the expansion chamber at the front end of the cold storage device periodically expands to generate cooling capacity, and the heat is transported to the hot end heat exchanger 31. Part of the heat in the hot end heat exchanger 31 is directly dissipated into the environment, and the other part is transported to the compressor 1 casing by the heat pipe and then discharged into the atmosphere, thereby accelerating heat dissipation.

[0041] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A coupled heat pipe low temperature mechanical refrigerator, characterized in that: include: A compressor (1), the compressor (1) comprising a shell heat exchanger (11); An expander (3), the expander (3) comprising a hot end heat exchanger (31); a connecting pipe (2), the connecting pipe (2) being provided between the compressor (1) and the expander (3) and connecting the compressor (1) and the expander (3); and, A heat pipe system (4), wherein the heat pipe system (4) is partially arranged between the shell heat exchanger (11) and the hot end heat exchanger (31), partially arranged in the shell heat exchanger (11), and partially arranged in the hot end heat exchanger (31).

2. The coupled heat pipe cryogenic mechanical refrigerator according to claim 1, characterized in that: The heat pipe system (4) comprises a gas section heat pipe pipeline (41), a condensation section heat pipe pipeline (42), a liquid section heat pipe pipeline (43) and an evaporation section heat pipe pipeline (44).

3. The coupled heat pipe cryogenic mechanical refrigerator according to claim 2, characterized in that: The evaporation section heat pipe circuit (44) is arranged in the hot end heat exchanger (31).

4. The coupled heat pipe cryogenic mechanical refrigerator according to claim 2, characterized in that: The condensation section heat pipe circuit (42) is arranged in the shell heat exchanger (11).

5. The coupled heat pipe cryogenic mechanical refrigerator according to claim 2, characterized in that: One end of the gas section heat pipe pipeline (41) is connected to the condensation section heat pipe pipeline (42), and the other end is connected to the evaporation section heat pipe pipeline (44).

6. The coupled heat pipe cryogenic mechanical refrigerator according to claim 2, characterized in that: One end of the liquid section heat pipe pipeline (43) is connected to the condensation section heat pipe pipeline (42), and the other end is connected to the evaporation section heat pipe pipeline (44).

7. The coupled heat pipe cryogenic mechanical refrigerator according to claim 2, characterized in that: The cross section of the liquid section heat pipe (43) is circular and its inner wall has a capillary structure.

8. The coupled heat pipe cryogenic mechanical refrigerator according to claim 2, characterized in that: The condensation section heat pipe line (42) is a groove opened in the outer shell of the compressor (1).

9. The coupled heat pipe cryogenic mechanical refrigerator according to claim 8, characterized in that: The channel is arranged helically around the compressor (1) casing.

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