CN209165834U - Refrigeration system and closed-loop refrigeration cycle circuit - Google Patents

Abstract

The utility model relates to a refrigeration system and a closed-loop refrigeration cycle. The refrigeration system comprises an outer container and a refrigeration circuit thermally coupled with a superconducting magnet coil. The refrigeration circuit is arranged in the outer container and used for communicating with the outer container. The external gas tank is connected to form a closed-loop refrigeration cycle; in use, when the superconducting magnet coil expires, the electrical energy is converted into heat energy, the refrigerant in the closed-loop refrigeration circuit is heated from liquid and evaporated into gas, and the pressure in the refrigeration circuit increases. . Since the gas tank is connected to the refrigeration circuit, the gas in the refrigeration circuit flows into the gas tank, and the gas in the refrigeration circuit is recovered by the gas tank, which can reduce the pressure bearing requirement on the refrigeration circuit; at the same time, since the gas tank is placed outside the outer container, The size and installation position of the gas tank are not limited by the inner space of the outer container.

Description

Refrigeration system and closed-loop refrigeration cycle

technical field

The utility model relates to the technical field of superconducting magnet coil refrigeration, in particular to a refrigeration system and a closed-loop refrigeration cycle.

Background technique

When the superconductor is cooled to a suitable low temperature, it acts as a conductor to transmit electrical energy without loss, and its resistance value is zero. This suitable temperature is called the "superconducting temperature" of the superconductor. Therefore, superconductors need to be provided with cooling systems to ensure that the superconductors operate at their superconducting temperature.

The general superconducting magnet cooling system is to immerse the superconducting magnet coil in the cooling liquid, and use the gasification process of the cooling liquid to cool the superconducting magnet coil. During this process, the vaporized gas will be released into the air, and the coolant needs to be replenished regularly.

In order to reduce the loss of refrigerant, the refrigerant is generally sealed in a closed-loop refrigeration circuit to prevent the volatilization of the refrigerant from being lost to the atmosphere. However, when the refrigerator cannot be refrigerated due to power failure or maintenance, or when the superconducting magnet expires, the energy stored in the superconducting magnet is converted into heat energy to vaporize the refrigerant. The pressure-bearing capacity of the closed-loop refrigeration circuit is relatively high.

Utility model content

Based on this, the present invention overcomes the defects of the prior art and provides a refrigeration system and a closed-loop refrigeration cycle to reduce the pressure-bearing capacity requirement of the closed-loop refrigeration circuit.

A refrigeration system is used for refrigeration of superconducting magnet coils, comprising an outer container and a refrigeration circuit thermally coupled with the superconducting magnet coil, the refrigeration circuit is arranged in the outer container and used to communicate with gas outside the outer container. The tanks are communicated to form a closed-loop refrigeration cycle.

In the above refrigeration system, when the superconducting magnet coil fails, the electric energy is converted into heat energy, and the refrigerant in the closed-loop refrigeration circuit is heated from liquid to gas, and the pressure in the refrigeration circuit increases. Since the gas tank is connected to the refrigeration circuit, the gas in the refrigeration circuit flows into the gas tank, and the gas in the refrigeration circuit is recovered by the gas tank, which can reduce the pressure bearing requirement on the refrigeration circuit; at the same time, since the gas tank is placed outside the outer container, The size and installation position of the gas tank are not limited by the inner space of the outer container. Under certain conditions, the pressure in the refrigeration circuit can be reduced by increasing the air storage space of the air tank as much as possible, so as to control the pressure in the refrigeration circuit within the design range.

In one of the embodiments, the outer container is provided with an inner container, and the refrigeration circuit is arranged in the inner container. In use, the inner container and the outer container can provide the refrigeration circuit with conditions for shielding the heat of the external environment, so as to reduce the influence of the heat of the external environment on the refrigeration effect of the refrigeration circuit.

In one embodiment, the refrigeration system further includes a pre-cooling pipe, the pre-cooling pipe is arranged in the outer container, one end of the pre-cooling pipe is communicated with the refrigeration circuit, and the other end of the pre-cooling pipe is in communication with the refrigeration circuit. The closed-loop refrigeration cycle is formed by being communicated with the gas tank located outside the outer container. In use, under the drainage of the pre-cooling pipe, the refrigerant in the pre-cooling pipe can reduce the temperature in the outer container, so as to reduce the temperature in the outer container.

In one embodiment, the outer container is provided with an inner container, the refrigeration circuit is provided in the inner container, and the pre-cooling pipe is provided in the outer container and thermally coupled with the inner container. In use, under the drainage of the pre-cooling tube, the refrigerant in the pre-cooling tube flows in the outer container, and then controls the temperature in the outer container, so that under the condition of external environment changes, it passes between the inner container and the outer container. The low temperature environment can reduce the influence of the external ambient temperature on the refrigeration effect of the refrigeration circuit.

In one embodiment, the refrigeration circuit is provided with a first guide port and a second guide port, and the first guide port and the second guide port are both used for communicating with the gas tank to form the closed-loop refrigeration circular loop. In use, when the air tank and the refrigerant in the refrigeration circuit flow relatively, the refrigerant can maintain a smooth flow through the first guide port and the second guide port.

In one of the embodiments, the refrigeration system further includes a diverter, a diversion cavity is arranged in the diversion device, the diversion cavity is communicated with the refrigeration circuit, and the diversion device is used for connecting with the air tank located outside the outer container. The communication forms a closed-loop refrigeration cycle. The structure of connecting the outer container and the refrigerating circuit with the diverter is simple, and it is convenient for the refrigerating circuit and the gas tank to be connected and installed.

In one embodiment, a blockable drainage port is provided on the drainage device, and the drainage port communicates with the drainage cavity. When the refrigeration circuit needs to be evacuated, the refrigeration circuit can be evacuated by connecting the drain port to the drainage device; when cooling the superconducting magnet coil, the closed-loop refrigeration cycle can be realized by blocking the drain port. to reduce refrigerant leakage.

In one embodiment, the drain includes a drain body and a cover, the drain body is provided with the drain cavity and a communication port communicating with the drain cavity, and the cover is detachably mounted on the drain body and cooperate with the communication port to seal the communication port. When the cover is removed, the refrigeration circuit communicates with the outside world through the communication port, so that the processing operation of the refrigeration circuit can be realized through the communication port; when the cover is installed on the body of the drain, the drain chamber can be separated from the outside world Come.

In one embodiment, the refrigeration circuit includes an accumulator and a cooling pipe thermally coupled to the superconducting magnet coil, the cooling pipe is in communication with the accumulator, the accumulator is used to collect the condensed refrigerant, and the accumulator is used to store the condensed refrigerant. The liquid container is used to communicate with the gas tank outside the outer container to form a closed-loop refrigeration cycle. In the process of cooling the superconducting magnet coil, the refrigerant in the accumulator flows to the cooling pipe, and through the thermal coupling between the cooling pipe and the superconducting magnet coil, the superconducting magnet coil exchanges heat with the refrigerant in the cooling pipe, absorbing the superconducting magnet coil. The liquid refrigerant vaporized with the heat of the magnet coils flows away from the cooling tubes.

In one embodiment, the refrigeration system further includes a first condenser, and the first condenser cooperates with the liquid accumulator to condense the refrigerant vaporized in the liquid accumulator. In the process of cooling the superconducting magnet coil, the gaseous refrigerant flows from the cooling pipe to the liquid accumulator, the gaseous refrigerant exchanges heat with the first condenser, and the gaseous refrigerant condenses into liquid refrigerant and is stored in the liquid accumulator In this way, the refrigerant circulates in the cooling pipe and the accumulator.

In one of the embodiments, the first condenser is arranged in a liquid accumulator. The manner in which the first condenser is arranged in the accumulator can facilitate the condensation of gaseous refrigerant into liquid refrigerant.

A closed-loop refrigerating cycle includes a communicating gas tank and the refrigerating system.

In the above closed-loop refrigeration cycle, the gas tank is arranged outside the outer container, and the gas tank is communicated with the refrigeration circuit to form a closed-loop refrigeration cycle. Since the gas tank is placed outside the outer container, the size and installation position of the gas tank are not limited by the inner space of the outer container. If the allowable conditions allow, the pressure in the refrigeration circuit is reduced by increasing the air storage space of the gas tank as much as possible, so as to control the pressure in the refrigeration circuit within a lower design range.

In one of the embodiments, the working pressure in the refrigeration circuit is -1 bar to 30 bar. When the working pressure of the refrigeration circuit is limited to -1 bar to 30 bar, the safety of the refrigeration circuit can be improved and the manufacturing difficulty can be reduced.

Description of drawings

1 is a schematic structural diagram of a refrigeration system according to an embodiment;

Fig. 2 is the internal structure diagram of outer layer container;

FIG. 3 is a partial enlarged view of A in FIG. 2 .

Description of reference numbers:

110, outer container, 110a, air extraction hole, 120, inner container, 210, refrigeration circuit, 210a, first guide port, 210b, second guide port, 211, accumulator, 212, cooling pipe, 220 , gas tank, 221, air outlet, 222, pressure gauge, 223, first pressure relief valve, 224, second pressure relief valve, 225, diversion hole, 230, pre-cooling pipe, 240, drainage device, 240a, drainage cavity, 240b, drain port, 240c, conducting port, 241, drain body, 241a, communicating port, 242, cover, 250, refrigerator, 251, first condenser, 252, second condenser, 260 , Connecting tube, 300, superconducting magnet coil, 400, self-cooling superconducting switch, 500, air duct.

Detailed ways

In order to facilitate the understanding of the present utility model, the present utility model will be more fully described below with reference to the related drawings. The preferred embodiments of the present invention are shown in the accompanying drawings. However, the present invention may be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that a thorough and complete understanding of the present disclosure is provided.

It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. In contrast, when an element is referred to as being "directly on" another element, there are no intervening elements present. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for the purpose of illustration only and do not represent the only embodiment.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the technical field to which the present invention belongs. The terms used in the description of the present invention herein are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

1 and 2 , in one embodiment, a refrigeration system is provided for superconducting magnet coil refrigeration, comprising an outer container 110 and a refrigeration circuit 210 thermally coupled with the superconducting magnet coil 300 , the refrigeration system is The circuit 210 is arranged in the outer container 110 and is used to communicate with the gas tank 220 located outside the outer container 110 to form a closed-loop refrigeration cycle.

The above refrigeration system, in use, when the superconducting magnet coil 300 expires, the electrical energy is converted into heat energy, the refrigerant in the closed-loop refrigeration circuit 210 is heated and evaporated from liquid to gas, and the pressure in the refrigeration circuit 210 increases. Since the air tank 220 is communicated with the refrigeration circuit 210, the gas in the refrigeration circuit 210 flows into the air tank 220, and the gas in the refrigeration circuit 210 is recovered by the air tank 220, which can reduce the pressure bearing requirement on the refrigeration circuit 210; The 220 is placed outside the outer container 110 , and the size and installation position of the gas tank 220 are not limited by the inner space of the outer container 110 . Under certain conditions, the pressure in the refrigeration circuit 210 can be reduced by increasing the air storage space of the air tank 220 as much as possible, so as to control the pressure in the refrigeration circuit 210 within the design range.

In one embodiment, the outer container 110 is provided with an inner container 120 , and the refrigeration circuit 210 is provided in the inner container 120 . In use, the inner container 120 and the outer container 110 can provide the refrigeration circuit 210 with conditions for shielding the external ambient heat, so as to reduce the influence of the external ambient heat on the cooling effect of the refrigeration circuit 210 .

Specifically, in this embodiment, the refrigeration system further includes a pre-cooling pipe 230, the pre-cooling pipe 230 is arranged in the outer container 110, and one end of the pre-cooling pipe 230 is communicated with the refrigeration circuit 210, so The other end of the pre-cooling pipe 230 is used to communicate with the gas tank 220 located outside the outer container 110 to form the closed-loop refrigeration cycle. In use, under the drainage of the pre-cooling pipe 230 , the refrigerant in the pre-cooling pipe 230 can reduce the temperature in the outer container 110 , so as to reduce the temperature in the outer container 110 .

Further, in this embodiment, the outer container 110 is provided with an inner container 120 , the refrigeration circuit 210 is provided in the inner container 120 , and the pre-cooling pipe 230 is provided in the outer container 110 and Thermally coupled to inner container 120 . In use, under the drainage of the pre-cooling pipe 230, the refrigerant in the pre-cooling pipe 230 flows in the outer container 110, and then the temperature in the inner container 120 is controlled. The low temperature environment between the outer containers 110 reduces the influence of the external ambient temperature on the refrigeration effect of the refrigeration circuit 210 .

It should be noted that the pre-cooling pipe 230 may be located between the inner container 120 and the outer container 110 , or may be located in the inner container 120 . When the pre-cooling pipe 230 is located in the inner container 120, the refrigerant flows in the inner container 120; when the pre-cooling pipe 230 is located between the inner container 120 and the outer container 110, the refrigerant flows in the inner container 120 and the outer container 110. Flow between the containers 110; when there are cooling pipes 230 between the inner container 120 and the outer container 110 and in the inner container 120, the refrigerant is between the inner container 120 and the outer container 110, and the inner container Flow within 120.

It should be noted that, in general use, the above-mentioned outer container 110 refers to a 300K container, and 300K is 300 Kelvin (temperature); that is, the external environment where the 300K container is located is room temperature. The inner container 120 refers to a 50K container, and 50K is 50 Kelvin (temperature); that is, the external environment where the 50K container is located is about 50K.

The outer container 110 is provided with at least one air extraction hole 110a, and the air extraction hole 110a is used to discharge the gas between the inner container 120 and the outer container 110, so that the space between the two is in a vacuum state, so as to achieve a vacuum Insulation.

3 , in one embodiment, the refrigeration circuit 210 is provided with a first flow guide port 210a and a second flow guide port 210b, and the first flow guide port 210a and the second flow guide port 210b are both used for The closed-loop refrigeration cycle is formed by communicating with the gas tank 220 . In use, when the air tank 220 and the refrigerant in the refrigeration circuit 210 flow relatively, the refrigerant can maintain a smooth flow through the first guide port 210a and the second guide port 210b.

Referring to FIG. 3 , in an embodiment, the refrigeration system further includes a drain 240 , a drain cavity 240 a is arranged in the drain 240 , the drain cavity 240 a communicates with the refrigeration circuit 210 , and the drain 240 It is used to communicate with the gas tank 220 located outside the outer container 110 to form a closed-loop refrigeration cycle. The structure of connecting the outer container 110 and the refrigeration circuit 210 with the diverter 240 is simple, and it is convenient for the refrigeration circuit 210 and the gas tank 220 to be connected and installed.

Specifically, in this embodiment, the refrigeration circuit 210 includes the above-mentioned pre-cooling pipe 230 and a communication pipe 260. One end of the communication pipe 260 is communicated with the first diversion port 210a, and the other end of the pre-cooling pipe 230 is connected to the first diversion port 210a. The drainage cavity 240a is in communication; one end of the pre-cooling pipe 230 is communicated with the second diversion port 201b, and the other end of the pre-cooling pipe 230 is communicated with the drainage cavity 240a.

Further, one end of the communication pipe 260 is communicated with the top of the drainage cavity 240a, and one end of the pre-cooling pipe 230 is communicated with the top of the drainage cavity 240a.

In one embodiment, the drain 240 is provided with a blockable drain port 240b, and the drain port 240b communicates with the drain cavity 240a. When the refrigeration circuit 210 needs to be evacuated, the refrigeration circuit 210 can be evacuated by connecting the drain port 240b to the drainage device; when cooling the superconducting magnet coil 300, the closed loop can be realized by blocking the drain port 240b. Refrigeration loop, so as to reduce refrigerant leakage.

In one embodiment, the drain 240 includes a drain body 241 and a cover 242. The drain body 241 is provided with the drain cavity 240a and a communication port 241a communicating with the drain cavity 240a. The cover 242 can It is disassembled and installed on the diverter body 241 and cooperates with the communication port 241a to seal the communication port 241a. When the cover body 242 is removed, the refrigeration circuit 210 communicates with the outside world through the communication port 241a, so that the processing operation of the refrigeration circuit 210 can be realized through the communication port 241a; when the cover body 242 is installed on the drain body 241, the The drainage cavity 240a is separated from the outside.

Specifically, in this embodiment, the drain port 240b is opened on the cover body 242 . A conducting port 240c is also opened on the cover body 242 , and the conducting port 240c is used to communicate with the gas tank 220 .

It should be noted that, generally, different devices have different types and specifications of connectors. In this embodiment, the drain port 240b is used for connecting the vacuum pump; the conducting port 240c is used for communicating with the gas tank 220 . Of course, if a joint adapter is used, the gas tank 220 can also be communicated with the drain port 240b.

In one embodiment, the refrigeration circuit 210 includes an accumulator 211 and a cooling pipe 212 thermally coupled to the superconducting magnet coil 300 , the cooling pipe 212 communicates with the accumulator 211 , and the accumulator 211 is used for collecting For the condensed refrigerant, the accumulator 211 is used to communicate with the gas tank 220 located outside the outer container 110 to form a closed-loop refrigeration cycle. During the process of cooling the superconducting magnet coil 300 , the refrigerant in the accumulator 211 flows to the cooling pipe 212 , and through the thermal coupling between the cooling pipe 212 and the superconducting magnet coil 300 , the superconducting magnet coil 300 and the cooling pipe 212 are thermally coupled. The heat exchange of the refrigerant is carried out, and the liquid refrigerant that absorbs the heat of the superconducting magnet coil 300 is vaporized and flows out of the cooling pipe 212 .

Specifically, in this embodiment, one end of the cooling pipe 212 communicates with the top of the drainage cavity 240a, and the other end of the cooling pipe 212 communicates with the bottom of the drainage cavity 240a. In use, the liquid refrigerant flows into the cooling tube 212 from the bottom of the drainage cavity 240a, and the gaseous refrigerant in the cooling tube 212 flows into the drainage cavity 240a from the top of the drainage cavity 240a.

It should be explained that the aforementioned "communication with the top of the drainage cavity 240a" and "communication with the bottom of the drainage cavity 240a" are relative concepts, and what is to be expressed here is that there is a height difference between the two positions, that is, the top of the drainage cavity 240a is higher than the top of the drainage cavity 240a. at the bottom of the drainage cavity 240a.

Further, in this embodiment, a self-cooling superconducting switch 400 is disposed between the inlet end and the outlet end of the cooling pipe 212 .

In an embodiment, the refrigeration system further includes a first condenser 251 , and the first condenser 251 cooperates with the liquid accumulator 211 to condense the refrigerant vaporized in the liquid accumulator 211 . In the process of cooling the superconducting magnet coil 300, the gaseous refrigerant flows from the cooling pipe 212 to the accumulator 211, the gaseous refrigerant exchanges heat with the first condenser 251, and the gaseous refrigerant condenses into liquid refrigerant and stores it In the accumulator 211 , the refrigerant circulates in the cooling pipe 212 and the accumulator 211 in this way.

In one embodiment, the first condenser 251 is disposed in the liquid accumulator 211 . The manner in which the first condenser 251 is disposed in the accumulator 211 can facilitate the condensation of gaseous refrigerant into liquid refrigerant.

Specifically, in this embodiment, a second condenser 252 is provided between the outer container 110 and the inner container 120 , and the second condenser 252 is provided between the inner container 120 and the outer container 110 . The second condenser 252 is thermally coupled with the cooling pipe 230 and the pre-cooling pipe 230 .

Specifically, in this embodiment, the refrigeration system includes a refrigerator 250, the refrigerator 250 is provided with a primary cold head and a secondary cold head, and the primary cold head is the second condenser 252, so The secondary cold head is the first condenser 252 .

Yet another embodiment provides a closed-loop refrigeration cycle including a communicating air tank 220 and the refrigeration system described in any one of the foregoing embodiments.

In the above closed-loop refrigeration cycle, the gas tank 220 is disposed outside the outer container 110, and the gas tank 220 communicates with the refrigeration circuit 210 to form a closed-loop refrigeration cycle. Since the gas tank 220 is placed outside the outer container 110 , the size and installation position of the gas tank 220 are not limited by the inner space of the outer container 110 . If the allowable conditions permit, the pressure in the refrigeration circuit 210 is reduced by increasing the air storage space of the air tank 220 as much as possible, so as to control the pressure in the refrigeration circuit 210 within a lower design range.

In one embodiment, the working pressure in the refrigeration circuit is -1 bar to 30 bar. When the working pressure of the refrigeration circuit is limited to -1 bar to 30 bar, the safety of the refrigeration circuit can be improved and the manufacturing difficulty can be reduced.

For example, the maximum storage volume of liquid helium in the liquid accumulator 211 is 10L. If the volume of the gas tank 220 is greater than 500L, the maximum working pressure in the closed-loop refrigeration cycle is less than 16bar.

Specifically, in this embodiment, an air guide tube 500 is provided between the air tank 220 and the diverter 240. One end of the air guide tube 500 is communicated with the air guide 240, and the other end of the air guide tube 500 is communicated with the air tank 220. The air conduit 500 enables the air tank 220 and the refrigeration circuit 210 to form a closed-loop refrigeration cycle. Of course, in other embodiments, the air conduit 500 can also adopt other structures instead to realize the communication between the air tank 220 and the flow guide 240 ; for example, the air tank 220 is directly disposed on the flow guide 240 .

In yet another embodiment, an air tank 220 is provided. The air tank 220 is provided with an air guide port 221 and a guide hole 225. The air guide port 221 is used to inflate or exhaust the air tank 220; 225 is used to communicate with the refrigeration circuit 210 to form a closed-loop refrigeration cycle. The gas tank 220 is also provided with a pressure gauge 222 and a first pressure relief valve 223 . The pressure gauge 222 is used to monitor and display the pressure value in the air tank 220; when the air pressure in the air tank 220 is greater than the first preset value, the first pressure relief valve 223 is opened to release the pressure.

Further, the gas tank 220 further includes a second pressure relief valve 224, and when the air pressure in the gas tank 220 is greater than a second preset value, the second pressure relief valve 224 is opened to release the pressure. The first preset value is smaller than the second preset value. Compared with the second pressure relief valve 224 , the pressure relief speed of the first pressure relief valve 223 is lower than that of the second pressure relief valve 224 .

Generally, all the gas refrigerant in the gas tank 220 can be stored in the accumulator 211 after being liquefied into a liquid refrigerant.

A method of injecting refrigerant for superconducting magnet coil refrigeration, comprising the following steps:

Injecting refrigerant: connecting the gas tank 220 located outside the outer container 110 and the refrigeration circuit 210 located in the outer container 110 to form a closed-loop refrigeration cycle, so that the high-pressure gaseous refrigerant in the gas tank 220 flows to the low-pressure refrigeration circuit 210 ; Condensing the refrigerant to condense the gaseous refrigerant in the refrigeration circuit 210 into a liquid refrigerant.

In the above-mentioned method of injecting refrigerant, since the air pressure in the air tank 220 is relatively high and the air pressure in the refrigeration cycle is relatively low, when the air tank 220 is communicated with the refrigeration circuit 210 to form a closed-loop cooling circuit, the gaseous refrigerant in the air tank 220 will be reduced. Quickly flow from the high-pressure gas tank 220 to the low-pressure refrigeration circuit 210, so that the air pressure in the gas tank 220 and the refrigeration circuit 210 are in a relatively balanced state; by condensing the gaseous refrigerant in the refrigeration circuit 210 into a liquid refrigerant, The air pressure in the refrigeration circuit 210 is continuously kept lower than the air pressure in the air tank 220 , so that the gaseous refrigerant automatically flows to the refrigeration circuit 210 by utilizing the pressure difference.

The above method is described below in conjunction with the above-mentioned refrigeration system:

The situation where the air pressure in the air tank 220 is higher than the air pressure in the refrigeration circuit 210 includes the following two situations:

Case 1: When the refrigerant storage amount in the closed-loop refrigeration cycle is lower than the preset amount, gaseous refrigerant is injected into the gas tank 220 , so that the air pressure in the gas tank 220 will be higher than the air pressure in the refrigeration circuit 210 .

Case 2: When the refrigeration circuit is connected to the atmosphere, the air in the refrigeration circuit 210 is discharged by means of vacuuming, so that the air pressure in the air tank 220 is higher than the air pressure in the refrigeration circuit 210 .

In one embodiment, the gaseous refrigerant is helium. After the helium gas is condensed into liquid helium, its temperature is low, and the liquid helium can be used to provide the required low temperature environment for the superconducting magnet coil 300 ; this can ensure the normal use of the superconducting magnet coil 300 .

In one embodiment, before injecting the refrigerant, the following steps are further included:

pre-cooling the refrigeration circuit 210; by pre-cooling the refrigeration circuit 210, the temperature in the outer container 110 can be reduced; in the process of injecting refrigerant into the refrigeration circuit 210, the temperature in the inner container 120 is relatively low, so the gaseous refrigeration can be improved The condensing speed of the refrigerant in the refrigeration circuit 210 is reduced, thereby reducing the injection time of the refrigerant.

In one embodiment, the pre-cooling refrigeration circuit 210 includes the following steps:

injecting pre-coolant into the refrigeration circuit 210 to reduce the temperature of the refrigeration circuit 210;

Pre-coolant in refrigeration circuit 210 is removed.

Using the refrigeration circuit 210 as the pre-coolant to pre-cool the outer container 110 and the structure of the refrigeration circuit 210 is simple; at the same time, the use of the refrigeration circuit 210 to complete both the pre-coolant transportation and the refrigerant transportation can facilitate the simplification of the interior of the outer container 110 structure.

In one embodiment, the pre-coolant is liquid nitrogen. Liquid nitrogen has the characteristics of low boiling point and low cost. Choosing liquid nitrogen as the pre-coolant can save the cost of pre-cooling.

The above method will be described below with reference to the above-mentioned refrigeration system: when injecting liquid nitrogen into the refrigeration circuit 210, the cover body 242 is opened, and the liquid nitrogen is injected from the port of the pre-cooling pipe 230 communicating with the drainage cavity 240a, and enters the pre-cooling pipe 212. The refrigerant flows to the accumulator 211 and the cooling pipe 212; the liquid nitrogen gasifies into nitrogen gas after absorbing heat, and the nitrogen gas is discharged from the nozzle of the communication pipe 260 connected to the drainage cavity 240a.

It should be noted that when the liquid nitrogen is injected into the pre-cooling tube 230, since the temperature in the outer container 110 is 270K-300K and the temperature of the liquid nitrogen is 77K, the liquid nitrogen that enters is rapidly vaporized, and the temperature of the nitrogen formed after vaporization is close to There is a large temperature difference between 100K, 270K and 100K, and forced convection is formed in the refrigeration circuit 210, so that the temperature in the outer container 110 is reduced to 77K.

In one embodiment, before pre-cooling the refrigeration circuit 210, the following steps are further included:

Purging and removing impurities: gaseous pre-coolant is introduced into the refrigeration circuit 210 to remove impurities in the refrigeration circuit 210 by filling the refrigeration circuit 210 with the gaseous pre-coolant.

By purging and removing impurities with the gaseous pre-coolant, a certain gas can be prevented from being condensed into solid impurities by the injected liquid pre-coolant, so that the solid impurities affect the normal use of the refrigeration circuit 210 .

It should be noted that the superconducting magnet coil 300 is made of superconducting material. When the preset liquid helium amount is stored in the accumulator 211, the superconducting coil can be subjected to current-energized excitation up-field.

The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity, all possible combinations of the technical features in the above-described embodiments are not described. However, as long as there is no contradiction between the combinations of these technical features, All should be regarded as the scope described in this specification.

The above-mentioned embodiments only represent several embodiments of the present utility model, and the descriptions thereof are specific and detailed, but should not be construed as a limitation on the scope of the utility model patent. It should be pointed out that for those of ordinary skill in the art, some modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent for this utility model shall be subject to the appended claims.

Claims (13)

1. a refrigeration system, is used for the refrigeration of superconducting magnet coil, it is characterized in that, comprise outer layer container and the refrigeration circuit thermally coupled with superconducting magnet coil, described refrigeration circuit is arranged in the outer layer container and is used for and is located in the refrigerating circuit. The air tanks outside the outer container are connected to form a closed-loop refrigeration cycle. 2 . The refrigeration system according to claim 1 , wherein an inner container is arranged in the outer container, and the refrigeration circuit is arranged in the inner container. 3 . 3 . The refrigeration system according to claim 1 , further comprising a pre-cooling pipe, the pre-cooling pipe is arranged in the outer container, one end of the pre-cooling pipe is communicated with the refrigeration circuit, and the pre-cooling pipe is connected to the refrigeration circuit. 4 . The other end of the pipe is used to communicate with the gas tank located outside the outer container to form the closed-loop refrigeration cycle. 4 . The refrigeration system according to claim 3 , wherein the outer container is provided with an inner container, and the refrigeration circuit is disposed in the outer container and thermally coupled with the inner container. 5 . 5. The refrigeration system according to claim 1, wherein the refrigeration circuit is provided with a first flow guide port and a second flow guide port, and the first flow guide port and the second flow guide port are both used for It communicates with the gas tank to form a closed-loop refrigeration cycle. 6. The refrigeration system according to any one of claims 1-5, further comprising a flow guide, wherein a flow guide is provided with a suction cavity, the flow cavity is communicated with the refrigeration circuit, and the flow guide is used for It communicates with the gas tank outside the outer container to form a closed-loop refrigeration cycle. 7 . The refrigeration system according to claim 6 , wherein a blockable drain port is provided on the drain device, and the drain port communicates with the drain chamber. 8 . 8 . The refrigeration system according to claim 6 , wherein the drain device comprises a drain body and a cover body, the drain body is provided with the drain cavity and a communication port communicating with the drain cavity, and the The cover body is detachably mounted on the flow guide body and cooperates with the communication port to seal the communication port. 9 . The refrigeration system according to claim 1 , wherein the refrigeration circuit comprises a liquid accumulator and a cooling pipe thermally coupled with the superconducting magnet coil, the cooling pipe is in communication with the liquid accumulator, and the liquid accumulator is in communication with the liquid accumulator. 10 . The accumulator is used to collect the condensed refrigerant, and the accumulator is used to communicate with the gas tank outside the outer container to form a closed-loop refrigeration cycle. 10 . The refrigeration system according to claim 9 , further comprising a first condenser, the first condenser cooperates with the accumulator to condense the refrigerant vaporized in the accumulator. 11 . 11. The refrigeration system according to claim 10, wherein the first condenser is arranged in a liquid accumulator. 12. A closed-loop refrigeration cycle, characterized in that it comprises a connected gas tank and the refrigeration system according to any one of claims 1-11. 13 . The closed-loop refrigeration cycle according to claim 12 , wherein the working pressure in the refrigeration circuit is -1 bar to 30 bar. 14 .