Gravity-assisted liquid nitrogen temperature zone rapid cooling integrated Stirling refrigeration system

Abstract

The invention discloses a gravity-assisted liquid nitrogen temperature zone rapid cooling integrated Stirling refrigeration system, and relates to the technical field of refrigeration equipment. The heat exchange loop comprises a condenser, a first connecting pipe, an evaporator and a second connecting pipe, the condenser and a cold head of the refrigerator are integrally formed, one end of the first connecting pipe communicates with a liquid outlet of the condenser, and the other end of the first connecting pipe communicates with a liquid inlet of the evaporator; one end of the second connecting pipe communicates with an air outlet of the evaporator, the other end of the second connecting pipe communicates with an air inlet of the condenser, and the evaporator is used for absorbing heat of a cooled object; a heat exchange medium circulates in the heat exchange loop; the evaporator is located below the condenser. The heat exchange loop can efficiently transfer heat, the condenser and the cold head in the refrigerating machine are integrally formed, the heat can be efficiently transferred between the cold head and the condenser, the heat transfer efficiency of the whole system can be improved, and rapid cooling of a liquid nitrogen temperature area is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of refrigeration equipment, and in particular to a gravity-assisted liquid nitrogen temperature zone rapid cooling integrated Stirling refrigeration system. Background Art

[0002] In the field of cryogenic technology, Stirling refrigerators play an important role in cooling liquid nitrogen and below. They have become a key cooling method in scenarios such as blackbody optical target cooling and vacuum cold traps. In these applications, there are high requirements for temperature control accuracy or installation flexibility, so Stirling refrigerators are gradually replacing liquid nitrogen to meet these special needs.

[0003] However, in the prior art, a traditional copper cold chain is usually used to connect the cold head of the refrigerator and the object to be cooled. In actual use, this traditional connection method has obvious disadvantages due to the presence of a certain heat transfer distance between the cold source (i.e., the cold head of the refrigerator) and the object to be cooled. Specifically, it will lead to a large heat transfer temperature difference, which means that during the cooling process, the heat transfer efficiency is not high, the temperature difference is large, and the cooling time is long, which affects the working efficiency and cooling effect of the entire refrigeration system, and cannot meet some application scenarios that have high requirements for the heat transfer temperature difference or high requirements for the cooling speed. Therefore, it is necessary to improve the cooling structure of the existing Stirling refrigeration system to overcome the above problems. Summary of the invention

[0004] The object of the present invention is to provide a gravity-assisted liquid nitrogen temperature zone rapid cooling integrated Stirling refrigeration system to solve the problems existing in the above-mentioned prior art and improve the heat transfer efficiency between the cold head and the cooled object.

[0005] To achieve the above object, the present invention provides the following solutions: The present invention provides a gravity-assisted liquid nitrogen temperature zone rapid cooling integrated Stirling refrigeration system, comprising: Refrigeration machine; A heat exchange loop, the heat exchange loop includes a condenser, a first connecting pipe, an evaporator and a second connecting pipe. The condenser is integrally formed with the cold head of the refrigerator. One end of the first connecting pipe is connected to the liquid outlet of the condenser, and the other end is connected to the liquid inlet of the evaporator. One end of the second connecting pipe is connected to the air outlet of the evaporator, and the other end is connected to the air inlet of the condenser. The evaporator is used to absorb heat from the cooled object. A heat exchange medium flows in the heat exchange loop. The evaporator is located below the condenser.

[0006] Preferably, the refrigerator is a liquid nitrogen temperature zone integrated Stirling refrigerator.

[0007] Preferably, a plurality of first hollow portions are provided on the cold head.

[0008] Preferably, the first hollow portion is in the shape of an elongated strip.

[0009] Preferably, a plurality of second hollow portions are provided on the condenser.

[0010] Preferably, all of the first hollow portions and all of the second hollow portions are distributed alternately.

[0011] Preferably, the first hollow portion is close to the condenser, and the second hollow portion is close to the cold head.

[0012] Preferably, the second hollow portion is in the shape of an elongated strip.

[0013] Preferably, the evaporator includes a liquid collecting pipe, an air collecting pipe and a plurality of heat exchange tubes, the liquid collecting pipe is closed at one end and is provided with a liquid inlet at the other end, the air collecting pipe is closed at one end and is provided with an air outlet at the other end, and each of the heat exchange tubes is connected to the liquid collecting pipe at one end and is connected to the air collecting pipe at the other end.

[0014] Preferably, the cold head and the condenser are both made of copper.

[0015] Compared with the prior art, the present invention has achieved the following technical effects: The gravity-assisted liquid nitrogen temperature zone rapid cooling integrated Stirling refrigeration system of the present invention improves the structure of the refrigeration system, including the setting of a heat exchange loop and the design of hollow parts on the cold head and the condenser, thereby effectively improving the heat transfer efficiency between the cold head and the cooled object, achieving rapid cooling of the liquid nitrogen temperature zone, improving the temperature control accuracy, and enhancing the application flexibility in various application scenarios, and has significant technical advantages and good application prospects.

[0016] Furthermore, the traditional Stirling refrigeration system uses a copper cold chain to connect the cold head of the refrigerator and the object to be cooled, which has a low heat transfer efficiency and a large heat transfer temperature difference and a long cooling time due to the heat transfer distance. The present invention constructs a heat exchange loop, including a condenser, a first connecting pipe, an evaporator, and a second connecting pipe, to form a relatively closed and continuous heat exchange medium flow path, so that heat can be transferred more efficiently within this loop. Through this integrated heat exchange loop design, compared with the traditional cold chain connection method, the temperature difference caused by long-distance heat transfer is reduced, thereby effectively improving the heat transfer efficiency between the cold head and the object to be cooled.

[0017] Furthermore, a plurality of long first hollow parts are provided on the cold head, and a plurality of long second hollow parts are provided on the condenser, and all the first hollow parts are staggered with all the second hollow parts, with the first hollow parts close to the condenser and the second hollow parts close to the cold head. The design of the first hollow part increases the contact surface area between the medium in the refrigerator and the cold head, and the design of the second hollow part increases the contact surface area between the heat exchange medium in the heat exchange loop and the condenser, thereby improving the heat transfer efficiency; and because the cold head and the condenser are integrally formed, when heat is transferred between the cold head and the condenser, it can be efficiently transferred between the two, which helps to improve the heat transfer efficiency of the entire system.

[0018] Furthermore, due to the improvement in the above-mentioned heat transfer efficiency, in the actual refrigeration process, the system can absorb and transfer the heat of the object being cooled more quickly, thereby achieving rapid cooling in the liquid nitrogen temperature zone. This can better meet the needs of quickly reaching the required low temperature state for application scenarios that have high requirements for cooling speed, such as blackbody optical target refrigeration, vacuum cold trap, etc., and improve the working efficiency and performance of the equipment in these application scenarios.

[0019] Furthermore, efficient heat transfer makes the refrigeration system's temperature control more precise. When heat can be transferred quickly and stably, the refrigerator can more accurately adjust parameters such as cooling power according to the set temperature, which helps to improve the temperature control accuracy of the entire refrigeration system and better meet the application occasions with high temperature control accuracy requirements.

[0020] Furthermore, a heat exchange medium flows in the heat exchange loop, and the evaporator is located below the condenser. Due to the effect of gravity, the heat exchange medium can flow more smoothly from the condenser to the evaporator. For example, the heat exchange medium in the condenser condenses into liquid after releasing heat, and the working fluid in the evaporator evaporates into gas after absorbing heat. Due to the effect of gravity, the liquid working fluid in the condenser flows downward, and the gas heat exchange medium in the evaporator flows upward, realizing the circulation of the heat exchange medium, without the need for external power (such as a pump, etc.), thereby reducing the complexity and energy consumption of the system.

[0021] Furthermore, the present invention adopts a liquid nitrogen temperature zone integrated Stirling refrigerator as a refrigerator, combined with optimized heat exchange loop and other structures, so that the entire refrigeration system can be installed and used more flexibly in different application scenarios, such as black body optical target refrigeration, vacuum cold trap, etc. Compared with the traditional refrigeration method that relies on liquid nitrogen, this integrated Stirling refrigeration system is not limited by liquid nitrogen supply, etc., and can be more conveniently laid out and adjusted according to the needs of specific application scenarios, thereby improving the flexibility of application. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only 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.

[0023] Figure 1 It is a structural schematic diagram of the gravity-assisted liquid nitrogen temperature zone rapid cooling integrated Stirling refrigeration system of the present invention; Figure 2 A partial structural diagram of the gravity-assisted liquid nitrogen temperature zone rapid cooling integrated Stirling refrigeration system of the present invention Figure 1 ; Figure 3 A partial structural diagram of the gravity-assisted liquid nitrogen temperature zone rapid cooling integrated Stirling refrigeration system of the present invention Figure 2 ; Figure 4 A partial structural diagram of the gravity-assisted liquid nitrogen temperature zone rapid cooling integrated Stirling refrigeration system of the present invention Figure 3 ; Figure 5 It is a structural schematic diagram of an evaporator in the gravity-assisted liquid nitrogen temperature zone rapid cooling integrated Stirling refrigeration system of the present invention; In the figure: 100, gravity-assisted liquid nitrogen temperature zone rapid cooling integrated Stirling refrigeration system; 10. Refrigerator; 11. Shock absorber; 12. Compressor; 13. Expander; 14. Cold head; 141. First hollow portion; 20. heat exchange loop; 21. condenser; 211. second hollow portion; 22. first connecting pipe; 23. second connecting pipe; 24. evaporator; 241. gas collecting pipe; 242. heat exchange pipe; 243. liquid collecting pipe. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only 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.

[0025] The object of the present invention is to provide a gravity-assisted liquid nitrogen temperature zone rapid cooling integrated Stirling refrigeration system to solve the problems existing in the above-mentioned prior art and improve the heat transfer efficiency between the cold head and the cooled object.

[0026] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0027] like Figures 1 to 5 As shown, this embodiment provides a gravity-assisted liquid nitrogen temperature zone rapid cooling integrated Stirling refrigeration system 100, comprising: Refrigerator 10; The heat exchange loop 20 includes a condenser 21, a first connecting pipe 22, an evaporator 24 and a second connecting pipe 23. The condenser 21 is integrally formed with the cold head 14 of the refrigerator 10. One end of the first connecting pipe 22 is connected to the liquid outlet of the condenser 21, and the other end is connected to the liquid inlet of the evaporator 24. One end of the second connecting pipe 23 is connected to the air outlet of the evaporator 24, and the other end is connected to the air inlet of the condenser 21. The evaporator 24 is used to absorb heat from the object to be cooled. A heat exchange medium flows in the heat exchange loop 20. The evaporator 24 is located below the condenser 21.

[0028] In this embodiment, the heat exchange medium flowing in the heat exchange loop 20 is nitrogen.

[0029] The gravity-assisted liquid nitrogen temperature zone rapid cooling integrated Stirling refrigeration system 100 of this embodiment uses a heat exchange loop 20 to transfer heat between the cold head 14 and the object to be cooled. Since the condenser 21 in the heat exchange loop 20 is integrally formed with the cold head 14 in the refrigerator 10, heat can be efficiently transferred between the cold head 14 and the condenser 21, which helps to improve the heat transfer efficiency of the entire system and achieve rapid cooling of the liquid nitrogen temperature zone. The heat exchange loop 20 forms a relatively closed and continuous heat exchange medium flow path, so that heat can be more efficiently transferred within this loop. Through this two-phase loop heat transfer method, the heat transfer efficiency is high, and the heat loss and temperature difference caused by long-distance heat transfer are reduced, thereby effectively improving the heat transfer efficiency between the cold head 14 and the object to be cooled.

[0030] Heat exchange medium flows in the heat exchange loop 20, and the evaporator 24 is located below the condenser 21. Due to the effect of gravity, the heat exchange medium can flow more smoothly from the condenser 21 to the evaporator 24. For example, the heat exchange medium (usually liquid) that absorbs heat in the condenser 21 evaporates into gas after the working fluid in the evaporator 24 absorbs heat. Due to the effect of gravity, the liquid working fluid in the condenser 21 flows downward, and the gas heat exchange medium in the evaporator 24 flows upward, realizing the circulation of the heat exchange medium. No external power (such as a pump, etc.) is required, thereby reducing the complexity and energy consumption of the system. In the evaporator 24, the heat exchange medium can absorb the heat of the cooled object more fully, because the stable medium flow can ensure that the heat exchange tubes 242 in each part of the evaporator 24 have enough heat exchange medium to participate in the heat exchange. The heat transfer process of the entire heat exchange loop 20 is optimized, and the refrigeration efficiency of the system is improved.

[0031] In the optional scheme of this embodiment, it is more preferred that the refrigerator 10 adopts a liquid nitrogen temperature zone integrated Stirling refrigerator. The liquid nitrogen temperature zone integrated Stirling refrigerator is a commercially available product well known to technicians, and usually includes a damper 11, a compressor 12, an expander 13 and a cold head 14. In this embodiment, the connection relationship and working principle between the damper 11, the compressor 12, the expander 13 and the cold head 14 are not described in detail. The liquid nitrogen temperature zone integrated Stirling refrigerator has a compact structure, high refrigeration efficiency, reliable and stable operation and a wide range of applications.

[0032] In the optional scheme of this embodiment, it is more preferred that a plurality of first hollow portions 141 are provided on the cold head 14. The design of the first hollow portions 141 increases the contact surface area between the medium in the refrigerator 10 (i.e., the refrigerant medium) and the cold head 14, thereby improving the heat exchange efficiency between the refrigerant medium and the cold head 14.

[0033] In this embodiment, the first hollow portion 141 is in an elongated strip shape, so that the first hollow portion 141 in an elongated strip shape can further increase the contact area between the refrigerant medium and the cold head 14 , thereby improving the heat exchange efficiency.

[0034] In the optional scheme of this embodiment, it is more preferred that a plurality of second hollow portions 211 are provided on the condenser 21. The design of the second hollow portions 211 increases the contact surface area between the heat exchange medium in the heat exchange loop 20 and the condenser 21, thereby improving the heat transfer efficiency between the heat exchange medium and the condenser 21.

[0035] In the optional scheme of this embodiment, it is more preferred that all the first hollow parts 141 and all the second hollow parts 211 are staggered. The staggered distribution of the long hollow parts can maximize the use of space to enhance heat transfer without increasing the overall volume of the cold head 14 and the condenser 21. This design enables the cold head 14 and the condenser 21 to achieve higher heat exchange efficiency in a limited space. Compared with other heat transfer enhancement methods that may increase the volume of the equipment, this staggered hollow design is more conducive to maintaining the compactness of the refrigeration system structure, and meets the requirements of refrigeration equipment in some space-constrained application scenarios, such as in some miniaturized vacuum cold trap devices, it is necessary to ensure efficient refrigeration while not making the equipment too large.

[0036] In the optional scheme of this embodiment, it is more preferred that the first hollow portion 141 is close to the condenser 21, and the second hollow portion 211 is close to the cold head 14. The first hollow portion 141 is close to the condenser 21, and when the temperature of the cold head 14 decreases, the temperature of the cold head 14 near the first hollow portion 141 will decrease rapidly. Since the second hollow portion 211 is close to the cold head 14, the heat of the heat exchange medium in the part of the condenser 21 close to the cold head 14 can be quickly released and quickly absorbed by the cold head 14, forming a smoother heat transfer cycle. It is like establishing an efficient "heat highway" between two adjacent areas, reducing the detours and obstacles in the heat transfer process, thereby improving the heat transfer efficiency.

[0037] In this embodiment, the second hollow portion 211 is in an elongated shape, so that the second hollow portion 211 in an elongated shape can further increase the contact area between the heat exchange medium and the condenser 21 and improve the heat exchange efficiency.

[0038] In the optional scheme of this embodiment, it is more preferred that the evaporator 24 includes a liquid collecting pipe 243, an air collecting pipe 241 and a plurality of heat exchange tubes 242, the liquid collecting pipe 243 is closed at one end and is provided with a liquid inlet at the other end, the air collecting pipe 241 is closed at one end and is provided with an air outlet at the other end, and each heat exchange tube 242 is connected to the liquid collecting pipe 243 at one end and is connected to the air collecting pipe 241 at the other end.

[0039] In the optional solution of this embodiment, it is more preferred that the cold head 14 and the condenser 21 are both made of copper; the cold head 14 and the condenser 21 are both made of copper, which can achieve efficient heat conduction. When the temperature of the cold head 14 decreases, its heat can be quickly transferred to the condenser 21 through the copper material.

[0040] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A gravity-assisted liquid nitrogen temperature zone rapid cooling integrated Stirling refrigeration system, characterized in that: include: Refrigeration machine; A heat exchange loop, the heat exchange loop includes a condenser, a first connecting pipe, an evaporator and a second connecting pipe. The condenser is integrally formed with the cold head of the refrigerator. One end of the first connecting pipe is connected to the liquid outlet of the condenser, and the other end is connected to the liquid inlet of the evaporator. One end of the second connecting pipe is connected to the air outlet of the evaporator, and the other end is connected to the air inlet of the condenser. The evaporator is used to absorb heat from the cooled object. A heat exchange medium flows in the heat exchange loop. The evaporator is located below the condenser.

2. The gravity-assisted liquid nitrogen temperature zone rapid cooling integrated Stirling refrigeration system according to claim 1, characterized in that: The refrigerator is a liquid nitrogen temperature zone integrated Stirling refrigerator.

3. The gravity-assisted liquid nitrogen temperature zone rapid cooling integrated Stirling refrigeration system according to claim 1, characterized in that: The cold head is provided with a plurality of first hollow parts.

4. The gravity-assisted liquid nitrogen temperature zone rapid cooling integrated Stirling refrigeration system according to claim 3, characterized in that: The first hollow portion is in a strip shape.

5. The gravity-assisted liquid nitrogen temperature zone rapid cooling integrated Stirling refrigeration system according to claim 3, characterized in that: The condenser is provided with a plurality of second hollow parts.

6. The gravity-assisted liquid nitrogen temperature zone rapid cooling integrated Stirling refrigeration system according to claim 5, characterized in that: All of the first hollow portions and all of the second hollow portions are distributed alternately.

7. The gravity-assisted liquid nitrogen temperature zone rapid cooling integrated Stirling refrigeration system according to claim 5, characterized in that: The first hollow portion is close to the condenser, and the second hollow portion is close to the cold head.

8. The gravity-assisted liquid nitrogen temperature zone rapid cooling integrated Stirling refrigeration system according to claim 5, characterized in that: The second hollow portion is in a strip shape.

9. The gravity-assisted liquid nitrogen temperature zone rapid cooling integrated Stirling refrigeration system according to claim 1, characterized in that: The evaporator includes a liquid collecting pipe, an air collecting pipe and a plurality of heat exchange tubes. The liquid collecting pipe is closed at one end and provided with a liquid inlet at the other end. The air collecting pipe is closed at one end and provided with an air outlet at the other end. Each of the heat exchange tubes is connected to the liquid collecting pipe at one end and connected to the air collecting pipe at the other end.

10. The gravity-assisted liquid nitrogen temperature zone rapid cooling integrated Stirling refrigeration system according to claim 1, characterized in that: The cold head and the condenser are both made of copper.

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