Cooling circulation system for magnet in liquid nitrogen temperature zone
By using a cooling circulation system consisting of a helium storage tank and a liquid nitrogen cooler, liquid nitrogen is used to cool the helium and drive its flow, thus solving the problems of low cooling efficiency and safety in the liquid nitrogen temperature range for magnets and achieving a highly efficient and safe magnet cooling effect.
Patent Information
- Application Number
- CN202422695419.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-06
- Publication Date
- 2025-11-14
- Estimated Expiration
- 2034-11-06
AI Technical Summary
Existing technologies for cooling magnets in liquid nitrogen temperature ranges suffer from low efficiency and safety issues. The vaporization and expansion of liquid nitrogen can cause vaporization impacts on cooling components, making it difficult to achieve stable cooling over a long period of time.
A cooling circulation system employing a helium storage tank and a liquid nitrogen cooler utilizes liquid nitrogen as a cooling medium to cool the helium. The helium flow is driven by a compressor, and combined with return gas parameter adjustment and a helium temperature recovery module, the risks associated with liquid nitrogen vaporization and expansion are avoided, achieving efficient and stable cooling.
It achieves efficient and safe cooling of magnets in the liquid nitrogen temperature range, avoids damage to cooling components caused by the vaporization and expansion of liquid nitrogen, and ensures the long-term stable operation of the cooling system.
Smart Images
Figure CN223552342U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of magnet cooling technology, specifically to a cooling circulation system for magnets in the liquid nitrogen temperature range. Background Technology
[0002] In related technologies, to make a magnet exhibit a superconducting or near-superconducting state, it is necessary to place the magnet in an extremely cold environment, such as sealing it in a cryogenic thermostat or pressure vessel containing liquid helium or other liquid coolants, in order to ensure that the magnet maintains its superconducting operation as much as possible. Therefore, cryogenic refrigeration systems are widely used to maintain the low-temperature environment of magnets.
[0003] For cooling in the liquid nitrogen temperature range, liquid nitrogen is usually used directly for cooling. However, liquid nitrogen is easy to vaporize, so it can only be used in an open system and cannot be operated for a long time. If circulation is required, a refrigerator must be added for cooling. Moreover, the vaporization and expansion of liquid nitrogen can cause vaporization impact on the cooling components, which poses a risk.
[0004] Therefore, how to efficiently and safely cool magnets in the liquid nitrogen temperature range has become an urgent technical problem to be solved. Utility Model Content
[0005] This application provides a cooling circulation system for magnets in the liquid nitrogen temperature range, in order to solve the technical problem of how to efficiently and safely continuously cool magnets in the liquid nitrogen temperature range in related technologies.
[0006] This application provides a cooling circulation system for a liquid nitrogen temperature range magnet, comprising: a helium storage tank, with its outlet end connected to the cooling input end of the magnet and its return end connected to the cooling output end of the magnet; and a liquid nitrogen cooler, using liquid nitrogen as the cooling medium, disposed on a pipeline connecting the outlet end of the helium storage tank and the cooling input end of the magnet; the helium in the helium storage tank flows out from its outlet end, is cooled by the liquid nitrogen cooler, flows into the magnet from the cooling input end of the magnet to cool the magnet, and flows out to the return end of the helium storage tank from the cooling output end of the magnet.
[0007] In one embodiment, a compressor is provided between the helium storage tank and the liquid nitrogen cooler to drive the flow of helium.
[0008] In one embodiment, the compressor is further provided with a cooling mechanism for cooling the compressor.
[0009] In one embodiment, the liquid nitrogen cooler includes a liquid nitrogen input device and a heat exchanger; the liquid nitrogen input device injects liquid nitrogen into the heat exchanger, and the pipeline connecting the outlet end and the cooling input end passes through the heat exchanger.
[0010] In one embodiment, a liquid level detection module is provided inside the heat exchanger, and the liquid level detection module is connected to the liquid nitrogen input device.
[0011] In one embodiment, the cooling circulation system for the liquid nitrogen temperature zone magnet further includes: a return gas parameter adjustment device, disposed between the cooling output end of the magnet and the return gas end of the helium storage tank, for adjusting the return gas parameter of the helium flowing out of the cooling output end of the magnet; a parameter acquisition device, disposed between the return gas parameter adjustment device and the return gas end; and an adjustment control module, respectively connected to the return gas parameter adjustment device and the parameter acquisition device.
[0012] In one embodiment, the return gas parameter adjustment device includes: a helium gas recovery module for recovering the helium gas flowing out of the cooling output end of the magnet to room temperature; the parameter acquisition module includes a return gas temperature sensor.
[0013] In one embodiment, the return gas parameter adjustment device further includes: a pressure reducing valve disposed between the helium gas warming module and the return gas end, for adjusting the return gas pressure; the parameter acquisition module includes a return gas pressure sensor.
[0014] In one embodiment, the regulation control module includes a PID control module.
[0015] In one embodiment, the cooling circulation system for the liquid nitrogen temperature zone magnet further includes a helium source connected to the helium storage tank.
[0016] In this embodiment, the magnet at liquid nitrogen temperature is cooled by the aforementioned cooling circulation system. Specifically, a helium storage tank and a liquid nitrogen cooler are provided. The liquid nitrogen cooler, which uses liquid nitrogen as the cooling medium, is used between the magnet and the helium storage tank to cool the helium in the helium storage tank. Low-temperature helium has a higher density and lower flow resistance at the same flow rate. After the helium reaches the liquid nitrogen temperature, it is introduced into the magnet, which can provide efficient circulating cooling of the magnet at the liquid nitrogen temperature level. This also avoids the risk of vaporization impact on the cooling components caused by the vaporization expansion of liquid nitrogen due to the circulating cooling. Attached Figure Description
[0017] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the present invention and, together with the description, serve to explain the principles of the present invention.
[0018] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0019] Figure 1 This is a modular schematic diagram of a cooling circulation system for a liquid nitrogen temperature range magnet provided according to an embodiment of this application;
[0020] Figure 2 This is a modular schematic diagram of another cooling circulation system for a liquid nitrogen temperature zone magnet provided according to an embodiment of this application.
[0021] Figure 3 This is a schematic diagram of a cooling circulation system for a liquid nitrogen temperature range magnet provided according to an embodiment of this application.
[0022] Figure Labels
[0023] 1. Helium storage tank; 2. Liquid nitrogen cooler; 21. Liquid nitrogen input device; 22. Heat exchanger; 23. Liquid level detection module; 3. Magnet; 31. Cooling input end; 32. Cooling output end; 4. Compressor; 41. Cooling mechanism; 5. Return gas parameter adjustment device; 51. Helium return temperature module; 52. Pressure reducing valve; 6. Return gas parameter acquisition module; 61. Return gas temperature sensor; 62. Return gas pressure sensor; 7. Adjustment and control module; 8. Helium source; 10. First pressure sensor; 20. First temperature sensor; 30. Second pressure sensor; 40. Second temperature sensor; 50. Third pressure sensor; 60. Third temperature sensor; 70. Gas mass flow meter. Detailed Implementation
[0024] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.
[0025] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.
[0026] As described in the background section, there are many problems with cooling in the liquid nitrogen temperature range in related technologies. The applicant attempted to use a helium circulation system as a cryogenic refrigeration system to maintain the low-temperature environment of the magnet. However, most existing small helium circulation systems cool the magnet by driving a helium fan and using a refrigerator for cooling, but this method is costly and the helium fan has a limited head, making it unsuitable for systems with large pressure drops.
[0027] Based on the above problems, this application proposes a cooling circulation system for magnets in the liquid nitrogen temperature range. For example... Figures 1 to 3 As shown, the cooling circulation system includes: a helium storage tank 1 and a liquid nitrogen cooler 2. The outlet 11 of the helium storage tank 1 is connected to the cooling input 31 of the magnet 3, and the return end 12 of the helium storage tank 1 is connected to the cooling output 32 of the magnet 3. The liquid nitrogen cooler 2 uses liquid nitrogen as the cooling medium and is installed on the pipeline connecting the outlet 11 of the helium storage tank 1 and the cooling input 31 of the magnet 3. The helium in the helium storage tank 1 flows out from its outlet 11, is cooled by the liquid nitrogen cooler 2, then flows into the magnet 3 from the cooling input 31 to cool the magnet 3, and finally flows out through the cooling output 32 of the magnet 3 to the return end 12 of the helium storage tank 1.
[0028] In this embodiment, the magnet 3 at liquid nitrogen temperature is cooled by a cooling circulation system. Specifically, a liquid nitrogen cooler 2, which uses liquid nitrogen as the cooling medium, is used between the magnet 3 and the helium storage tank 1 to cool the helium flowing out of the helium storage tank 1. The low-temperature helium has a higher density and lower flow resistance at the same flow rate. After the helium reaches the liquid nitrogen temperature, it is introduced into the magnet 3, which can efficiently circulate and cool the magnet 3 at the liquid nitrogen temperature level. This also avoids the risk of vaporization impact on the cooling components caused by the vaporization expansion of liquid nitrogen due to the use of liquid nitrogen circulation cooling.
[0029] In one embodiment, a compressor 4 is disposed between the helium storage tank 1 and the liquid nitrogen cooler 2 to drive the flow of helium. The compressor 4 provides a high-pressure environment and a large driving force for the cooling circulation system, improving the helium flow efficiency and further enhancing the cooling efficiency of the magnet 3. To ensure the stable operation of the compressor 4, in one embodiment, a cooling mechanism 41 is also provided on the compressor 4 for cooling the compressor 4. In this embodiment, the cooling mechanism 41 can be a water-cooling mechanism or an air-cooling mechanism.
[0030] In one embodiment, the liquid nitrogen cooler 2 includes a liquid nitrogen input device 21 and a heat exchanger 22. The liquid nitrogen input device 21 injects liquid nitrogen into the heat exchanger 22, and the pipe connecting the outlet end 11 and the cooling input end 31 passes through the heat exchanger 22. In this embodiment, the cooling medium of the heat exchanger 22 is liquid nitrogen, and the pipe connecting the outlet end 11 and the cooling input end 31 can stably cool the helium gas before it enters the magnet 3 to the liquid nitrogen temperature under the cooling of liquid nitrogen. At the same time, injecting liquid nitrogen into the heat exchanger 22 through the liquid nitrogen input device 21 can provide a continuous cold source for the heat exchanger 22, ensuring that the helium gas entering the magnet 3 can be maintained at the liquid nitrogen temperature for a long time.
[0031] In one embodiment, to ensure a sufficient cooling capacity for the helium gas, a liquid level detection module 23 is also provided in the heat exchanger 22, and the liquid level detection module 23 is connected to the liquid nitrogen input device 21. The exemplary liquid level detection module 23 can also be a photoelectric liquid level sensor or a mechanical liquid level sensor.
[0032] In this embodiment, the liquid nitrogen input device 21 may include a liquid nitrogen source and a cryogenic valve. The cryogenic valve opens after receiving a signal from the liquid level detection module 23 that indicates insufficient liquid nitrogen level, so that the liquid nitrogen source replenishes the heat exchanger with liquid nitrogen.
[0033] In one embodiment, to ensure the stability of the helium flow rate in the cooling circulation system, a return gas parameter regulating device 5 is also provided in the cooling circulation system. This device is positioned between the cooling output end 32 of the magnet 3 and the return gas end 12 of the helium storage tank 1 to regulate the return gas parameter of the helium flowing out from the cooling output end 32 of the magnet 3. A parameter acquisition device 6 is positioned between the return gas parameter regulating device 5 and the return gas end 12. An adjustment control module 7 is connected to both the return gas parameter regulating device 5 and the parameter acquisition device 6. The adjustment control module 7 uses the return gas parameters acquired by the parameter acquisition device 6 to control the return gas parameter regulating device to adjust the return gas parameters in real time, ensuring that the return gas parameters are within a set range. This improves the reliability and safety of the cooling circulation system and meets the requirements for long-term operation of the cooling circulation system.
[0034] In one embodiment, the return gas parameters may include return gas temperature and return gas pressure. After the cooled helium gas cools the magnet 3, the helium flowing out of the magnet 3 remains at low temperature, and the coldness continues to accumulate. Excessively low return gas temperature can cause temperature fluctuations in the returned helium, thus affecting the stability of the flow input. Especially when a compressor 4 is installed on the pipeline at the outlet 11, an excessively low return gas temperature will adversely affect the compressor 4. Therefore, in this embodiment, the return gas temperature needs to be adjusted to room temperature. The return gas parameter adjustment device 5 includes: a helium gas warming module 51, used to warm the helium flowing out of the cooling output end 32 of the magnet 3 to room temperature; and a parameter acquisition device 6 including a return gas temperature sensor 61. For example, the helium gas warming module 51 can use a heating device to heat the return gas to room temperature. The adjustment and control module 7 adjusts the heating device based on the returned gas temperature collected by the return gas temperature sensor 61 to ensure that the return gas temperature is stably maintained at the set temperature. In this embodiment, a variable frequency heating device can be used.
[0035] Furthermore, the return gas pressure affects the helium output flow rate, especially when a compressor 4 is installed on the pipeline at the outlet 11, significantly impacting the output flow rate of the compressor 4. Therefore, in this embodiment, the return gas pressure needs to be adjusted in real time. The return gas parameter adjustment device 5 further includes a pressure reducing valve 52, located between the helium reheating module and the return gas end 12, used to adjust the return gas pressure. The parameter acquisition device 6 includes a return gas pressure sensor 62. The adjustment control module 7 adjusts the opening of the pressure reducing valve 52 based on the reheated return gas pressure collected by the return gas pressure sensor 62 to ensure that the return gas pressure is stably maintained at the set pressure.
[0036] In one embodiment, the adjustment control module 7 can be a PID control module, or a single-chip microcomputer control unit or MCU.
[0037] In one embodiment, a gas mass flow meter 70 is provided between the pressure reducing valve 52 and the helium storage tank 1.
[0038] In one embodiment, in order to ensure that the system has sufficient circulating helium and has a pressure stabilization function, it may also include a helium source 8, such as a helium cylinder connected to a helium storage tank 1 to continuously supply helium to the helium storage tank 1.
[0039] In one embodiment, the cooling circulation system may also be equipped with multiple pressure sensors, temperature sensors, and flow meters. For example, a first pressure sensor 10 and a first temperature sensor 20 may be installed on the pipeline between the compressor 4 and the liquid nitrogen cooler 2; a second pressure sensor 30 and a second temperature sensor 40 may be installed on the pipeline between the liquid nitrogen cooler 2 and the cooling input end 31 of the magnet 3; and a third pressure sensor 50 and a third temperature sensor 60 may be installed between the cooling output end 32 of the magnet 3 and the return gas parameter adjustment device 5, so as to collect data of the cooling circulation system during operation, which facilitates data collection and subsequent data analysis.
[0040] It should be noted that, in addition to magnets made of superconducting tapes, magnets made of conventional conductive materials, such as copper conductors, exhibit excellent conductivity at extremely low temperatures, such as -150 degrees Celsius or even -273 degrees Celsius (i.e., absolute zero), due to the extremely low resistivity of copper. Therefore, the conductor materials mentioned in this application are not limited to superconducting tapes or copper, but include any conductor material whose resistivity can be reduced and conductivity improved through the aforementioned cooling cycle system.
[0041] In the above embodiments of this application, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.
[0042] The above description is only a preferred embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this application, and these improvements and modifications should also be considered within the scope of protection of this application.
Claims
1. A cooling circulation system for magnets in the liquid nitrogen temperature range, characterized in that, include: A helium storage tank, with its outlet end connected to the cooling input end of the magnet and its return end connected to the cooling output end of the magnet; A liquid nitrogen cooler, using liquid nitrogen as the cooling medium, is installed on the pipeline connecting the outlet end of the helium storage tank and the cooling input end of the magnet. Helium gas in the helium storage tank flows out from its outlet end, is cooled by the liquid nitrogen cooler, flows into the magnet from the cooling input end of the magnet to cool the magnet, and flows out to the return end of the helium storage tank from the cooling output end of the magnet.
2. The cooling circulation system for liquid nitrogen temperature range magnets as described in claim 1, characterized in that, A compressor is installed between the helium storage tank and the liquid nitrogen cooler to drive the flow of helium.
3. The cooling circulation system for liquid nitrogen temperature range magnets as described in claim 2, characterized in that, The compressor is also equipped with a cooling mechanism for cooling the compressor.
4. The cooling circulation system for liquid nitrogen temperature range magnets as described in claim 1, characterized in that, The liquid nitrogen cooler includes a liquid nitrogen input device and a heat exchanger; the liquid nitrogen input device injects liquid nitrogen into the heat exchanger, and the pipeline connecting the outlet end and the cooling input end passes through the heat exchanger.
5. The cooling circulation system for a liquid nitrogen temperature range magnet as described in claim 4, characterized in that, The heat exchanger is equipped with a liquid level detection module, which is connected to the liquid nitrogen input device.
6. The cooling circulation system for a liquid nitrogen temperature range magnet as described in any one of claims 1 to 3, characterized in that, Also includes: A return gas parameter adjustment device is installed between the cooling output end of the magnet and the return gas end of the helium storage tank to adjust the return gas parameter of the helium flowing out of the cooling output end of the magnet. A parameter acquisition device is installed between the return gas parameter adjustment device and the return gas end; The adjustment and control module is connected to the return gas parameter adjustment device and the parameter acquisition device, respectively.
7. The cooling circulation system for a liquid nitrogen temperature range magnet as described in claim 6, characterized in that, The return gas parameter adjustment device includes: The helium recovery module is used to restore the helium flowing out of the cooling output end of the magnet to room temperature; The parameter acquisition device includes a return gas temperature sensor.
8. The cooling circulation system for a liquid nitrogen temperature range magnet as described in claim 7, characterized in that, The return gas parameter adjustment device further includes: A pressure reducing valve is installed between the helium reheating module and the return gas end to regulate the return gas pressure. The parameter acquisition device includes a return air pressure sensor.
9. The cooling circulation system for a liquid nitrogen temperature range magnet as described in claim 6, characterized in that, The regulation and control module includes a PID control module.
10. The cooling circulation system for a liquid nitrogen temperature range magnet as described in claim 1, characterized in that, Also includes: A helium source is connected to the helium storage tank.