Low-temperature circulating pump and low-temperature circulating refrigerating system

Abstract

The invention discloses a low-temperature circulating pump and a low-temperature circulating refrigerating system, and the low-temperature circulating pump comprises a storage part which comprises a first storage part and a second storage part which are connected in series through a super-leakage device so as to store superfluid, and the first storage part and the second storage part are respectively a paramagnetic salt storage part and an antiferromagnetic salt storage part; the pipeline is connected with the two ends of the storage part so that the superfluid can move along the pipeline to achieve heat exchange; the magnet is arranged on the outer side of the first storage part and the outer side of the second storage part, a variable magnetic field is provided for the first storage part and the second storage part, and a temperature difference is formed between the first storage part and the second storage part through the magnetocaloric effect; and the circulating flow of the superfluid in the low-temperature circulating pump is realized. The superfluid is circulated through the magnetothermal effect of the paramagnetic salt and the antiferromagnetic salt, the superfluid is always kept in a liquid state in the process, and therefore large-flow and continuous refrigeration circulation is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of ultra-low temperature refrigeration, and in particular to a low temperature circulation pump and a low temperature circulation refrigeration system. Background Art

[0002] The ultra-low temperature zone refers to a low temperature environment with a temperature below 1K. Under ultra-low temperatures, basic physics research can be carried out, and an extreme low temperature environment can also be provided for space exploration and quantum computing. Ultra-low temperature refrigeration technology is in demand in many fields such as high-energy physics, superconductivity, aerospace, and atomic energy science. Superfluid is a state of matter that is often formed under ultra-low temperature conditions. Its characteristic is that the internal friction coefficient is zero, so the superfluid can flow quickly along the flow channel, so it can be used as a refrigerant in an ultra-low temperature refrigeration system to achieve ultra-low temperature refrigeration, thereby providing an ultra-low temperature system.

[0003] The liquefaction temperature of helium (He) at one atmosphere of pressure is 4.2K, while the internal friction coefficient of liquid helium at 2.17K is zero, forming He II. At this time, He II contains ordinary fluid He and superfluid He, which can be used in ultra-low temperature refrigeration systems as a refrigerant. Continuous ultra-low temperature refrigeration using He as a refrigerant requires the use of an oil-free dry pump to drive the circulation of superfluid helium, but this design requires the superfluid helium to be heated to room temperature before entering the cold finger through multiple stages of pre-cooling during the circulation process. This process consumes a lot of energy; at the same time, due to the large volume of the gas loop from the cryogenic chamber to room temperature, it is not conducive to the realization of a compact ultra-low temperature system. A refrigeration system in which the gas loop does not pass through room temperature is called a cryogenic cycle refrigeration system. The prior art proposes to use an adsorption pump and a condensation pump to achieve low-temperature cycle refrigeration, wherein the condensation pump collects and liquefies gaseous helium in a low-temperature environment, and then allows the liquid helium to re-enter the refrigeration cycle. However, the condensation pump needs to continuously consume the low-temperature cooling capacity of adiabatic demagnetization during operation, so it will enter a low-temperature regeneration period after working for a period of time, and cannot achieve a large-flow and continuous refrigeration cycle; the adsorption pump uses an adsorbent to adsorb helium to form a negative pressure, thereby achieving a circulating flow of helium in the pump, but the existing adsorbents such as activated carbon and other materials have weak adsorption capacity for helium, and the adsorbent also needs to be reactivated after working for a period of time, so it is also impossible to achieve a large-flow and continuous refrigeration cycle.

[0004] Therefore, the prior art still needs to be improved and developed. Summary of the invention

[0005] In view of the above-mentioned deficiencies in the prior art, an object of the present invention is to provide a low-temperature circulation pump and a low-temperature circulation refrigeration system, aiming to solve the problem in the prior art that using He as an ultra-low temperature refrigerant cannot achieve a large-flow and continuous refrigeration cycle.

[0006] A first aspect of the present invention provides a low-temperature circulation pump, comprising:

[0007] A storage part, the storage part comprises a first storage part and a second storage part connected in series through a superdrain to store superfluid, and the first storage part and the second storage part are a paramagnetic salt storage part and an antiferromagnetic salt storage part respectively;

[0008] A pipeline, wherein the pipeline connects two ends of the storage part so that the superfluid moves along the pipeline to achieve heat exchange;

[0009] A magnet is arranged on the outside of the first storage part and the second storage part, providing a changing magnetic field for the first storage part and the second storage part, forming a temperature difference between the first storage part and the second storage part through a magnetocaloric effect, and realizing the circulation of the superfluid in the low-temperature circulation pump.

[0010] In one embodiment, the superfluid is 3 He and 4 Superfluidity in He mixed solution 4 He or pure 4 Superfluidity in He 4 He.

[0011] In one embodiment, the first storage portion and the second storage portion are cylindrical structures.

[0012] In one embodiment, one of the first storage section and the second storage section stores paramagnetic salt particles and the superfluid to form the paramagnetic salt storage section, and the other stores antiferromagnetic salt particles and the superfluid to form the antiferromagnetic salt storage section.

[0013] In one embodiment, the magnet is a superconducting magnetic coil surrounding the first storage portion and the second storage portion.

[0014] In one embodiment, the magnet provides a linearly changing magnetic field to the first storage portion and the second storage portion.

[0015] In one embodiment, the super leak is a material having micro-nano pores.

[0016] In one embodiment, the pipeline connection is provided with a functional part, which is a component using superfluid helium as a refrigerant, including a heat exchanger, a dilution refrigeration unit or a superfluid pulse tube unit.

[0017] In one embodiment, valves are provided at the connections between the two ends of the storage portion and the pipeline.

[0018] A second aspect of the present invention provides a low-temperature circulation refrigeration system, comprising a low-temperature circulation pump as described in any one of the above items.

[0019] The present invention discloses a low-temperature circulation pump and a low-temperature circulation refrigeration system, wherein the low-temperature circulation pump comprises: a storage part, wherein the storage part comprises a first storage part and a second storage part connected in series through a superdrain to store a superfluid, and the first storage part and the second storage part are a paramagnetic salt storage part and an antiferromagnetic salt storage part respectively; a pipeline, wherein the pipeline connects the two ends of the storage part so that the superfluid moves along the pipeline to realize heat exchange; and a magnet, wherein the magnet is arranged on the outside of the first storage part and the second storage part, and provides a variable magnetic field for the first storage part and the second storage part, and forms a temperature difference between the first storage part and the second storage part through a magnetocaloric effect, so as to realize the circulation flow of the superfluid in the low-temperature circulation pump. The present invention circulates the superfluid through the magnetocaloric effect of paramagnetic salt and antiferromagnetic salt, and the superfluid always remains in a liquid state during the process, thereby realizing a large flow and continuous refrigeration cycle. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, 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 present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0021] Figure 1 It is a schematic diagram of the structure of the low-temperature circulation pump described in the present invention.

[0022] Figure 2 It is a schematic diagram of the relationship between the magnetic field change and the temperature change in the low-temperature circulation pump of the present invention. DETAILED DESCRIPTION

[0023] The present invention provides a low temperature circulation pump and a low temperature circulation refrigeration system. To make the purpose, technical solution and effect of the present invention clearer and more specific, the present invention is further described in detail below. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0024] It should be noted that the directions or positional relationships indicated by terms such as “center”, “up”, “down”, “left”, “right”, “inside”, “outside”, “vertical” and “horizontal” are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention and simplifying the description. They do not indicate or imply that the structure referred to must have a specific direction or must be constructed in a specific direction, and should not be understood as a limitation on the present invention.

[0025] In addition, unless there is a special limitation on the articles in the text, "one" and "the" may refer to a single one or multiple ones. If there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. 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 the 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 invention.

[0026] The boiling point of helium is 4.2K, which is much lower than other gases. Therefore, the separation of helium was not achieved until the end of the 19th century. With the successful liquefaction of helium, phenomena such as superconductivity and superfluidity have been discovered one after another, and the field of low-temperature physics has made great progress. Superfluidity is a quantum effect in the macroscopic range, which is often formed under ultra-low temperature conditions. Objects with superfluid properties are called superfluids. They are characterized by extremely high thermal conductivity and zero internal friction coefficient, that is, completely inviscid. Therefore, superfluids can flow endlessly without friction. At the same time, due to their extremely high thermal conductivity, superfluids are an excellent refrigerant and are often used to realize refrigeration systems in ultra-low temperature environments.

[0027] When the temperature drops to 2.17K, helium atoms occupy the lowest energy ground state. At this time, helium atoms gather to form a superfluid, which can overcome gravity and flow upward, pass through extremely small pores and has extremely high heat conduction efficiency. Therefore, superfluid helium has broad application prospects in cooling objects to ultra-low temperature refrigeration.

[0028] Superfluid helium (helium II, He II) has special two-fluid properties, which can be described by the two-fluid model, that is, superfluid helium is composed of two independent, mutually permeable fluids. One is the condensed part in the ground state, with entropy equal to zero and no viscosity, which is a superfluid; the other is the normal fluid in the excited state (uncondensed), with entropy not equal to zero and viscosity, which is an ordinary fluid. The sum of the densities of the two fluids is equal to the total density of He II, and the ratio between the two changes with temperature. In this case, superfluid helium has a fountain effect, also called the thermo-mechanical effect, which refers to the phenomenon that superfluid helium flows in capillaries due to temperature differences. This is because superfluid helium absorbs heat when heated, and the superfluid portion at the heated end of the capillary is reduced. Since only superfluid can flow through the capillary, the superfluid component at the unheated end flows through the capillary to the heated end, causing the liquid level at the heated end of the capillary to rise, forming a pressure difference, thereby causing the superfluid helium to eject, which is manifested as an increase in pressure on the hotter side, driving the inviscid superfluid helium to flow to the colder side, thus forming a pressure difference and inducing continuous flow.

[0029] Therefore, the present invention utilizes the characteristics of superfluids, and forms a temperature difference between superfluids, thereby realizing the circulation of superfluids in the system through the fountain effect. The superfluid remains in a liquid state in the system, and no additional gas circuit is required. A compact refrigeration system structure can be achieved, and no heating and cooling process is required. The energy consumption is low and there is no low-temperature regeneration period, and a large flow and continuous refrigeration effect can be achieved. Further, the present invention adjusts the temperature of the superfluid under ultra-low temperature conditions through the magnetocaloric effect, thereby achieving precise temperature control. Among them, the magnetocaloric effect refers to the fact that the temperature of a magnetic material changes synchronously with the change of the magnetic field when the magnetic field changes. For different materials and different magnetic field change ranges, the temperature change law caused by the magnetocaloric effect is not the same. For paramagnetic salts, the temperature is proportional to the magnetic field strength; for antiferromagnetic salts, it is inversely proportional. In this way, the present invention sets adjacent paramagnetic salt areas and antiferromagnetic salt areas to form a temperature difference between superfluids, so that the superfluid circulates in the circulating pump, achieving a large flow and continuous refrigeration effect.

[0030] Specifically, the present invention provides a low-temperature circulation pump, wherein, as Figure 1As shown, the low-temperature circulation pump includes: a storage part 100, a pipeline 200 and a magnet 300. The storage part 100 includes a first storage part 110 and a second storage part 120 connected in series through a superdrain 130 to store superfluids respectively, and the first storage part 110 and the second storage part 120 are a paramagnetic salt storage part and an antiferromagnetic salt storage part respectively; the pipeline 200 connects the two ends of the storage part 100 so that the superfluid moves along the pipeline 200 to achieve heat exchange; the magnet 300 is arranged on the outside of the first storage part 110 and the second storage part 120 to provide a changing magnetic field for the first storage part 110 and the second storage part 120, and a temperature difference is formed between the first storage part 110 and the second storage part 120 through the magnetocaloric effect, so as to realize the circulation of the superfluid in the low-temperature circulation pump. By selecting one of the first storage section 110 and the second storage section 120 to form a paramagnetic salt storage section and the other to form an antiferromagnetic salt storage section, the magnetocaloric effect between the first storage section 110 and the second storage section 120 is opposite, so that when the magnet 300 applies the same changing magnetic field to the first storage section 110 and the second storage section 120, a temperature difference is formed between the first storage section 110 and the second storage section 120, so that the superfluid stored in the first storage section 110 and the second storage section 120 circulates along the pipeline 200 under the action of the fountain effect, thereby achieving a large-flow and continuous cooling effect.

[0031] In one embodiment, the superfluid is 3 He and 4 Superfluidity in He mixed solution 4 He or pure 4 Superfluidity in He 4 He, different superfluid helium is selected based on different working conditions. Whether it is a mixed liquid or pure 4 He, there are two kinds of helium in the superfluid helium at the same time, which has the properties of two fluids. The ratio of the two kinds of helium will change with the temperature, so that when the temperature changes, the content of superfluid helium in the fluids in different temperature areas is different. The superfluid helium flows spontaneously through the potential difference to form a pressure difference, thereby inducing a fountain effect, making the superfluid circulate in the low-temperature circulation pump, avoiding the low-temperature regeneration period to ensure continuous refrigeration, and avoiding the process of heating the superfluid to room temperature and then condensing, thereby reducing the overall energy consumption.

[0032] In one embodiment, the first storage portion 110 and the second storage portion 120 are cylindrical structures to ensure uniform stress of the whole, extend the service life, and avoid leakage of the superfluid stored inside.

[0033] In one embodiment, one of the first storage section 110 and the second storage section 120 stores paramagnetic salt particles and the superfluid to form the paramagnetic salt storage section, and the other stores antiferromagnetic salt particles and the superfluid to form the antiferromagnetic salt storage section. Optionally, the first storage section 110 is the paramagnetic salt storage section, and the second storage section 120 is the antiferromagnetic salt storage section; or the first storage section 110 is the antiferromagnetic salt storage section, and the second storage section 120 is the paramagnetic salt storage section. As long as the magnetocaloric effect between the first storage section 110 and the second storage section 120 is opposite, the changing magnetic field can be effectively utilized to form a more obvious temperature gradient between the first storage section 110 and the second storage section 120, so as to realize the circulation of the superfluid in the low-temperature circulation pump with a smaller magnetic field change, and lower energy consumption.

[0034] In one embodiment, the magnet 300 is a superconducting magnetic coil surrounding the first storage part 110 and the second storage part 120. Specifically, the magnet 300 is an integrated superconducting magnetic coil, which surrounds the first storage part 110 and the second storage part 120 at the same time, thereby making the overall structure of the cryogenic circulation pump more compact, reducing the use of superconducting magnets, and further reducing the cost of the cryogenic circulation pump.

[0035] In one embodiment, the magnet 300 provides a linearly changing magnetic field to the first storage section 110 and the second storage section 120, and the greater the amplitude of the magnetic field change, the better the performance of the cryogenic circulation pump. By setting the magnetocaloric effect between the first storage section 110 and the second storage section 120 to be opposite, the required temperature gradient can be achieved through a smaller magnetic field change. Optionally, the lower limit of the changing magnetic field is 0, and the upper limit of the changing magnetic field is set based on the required performance of the cryogenic circulation pump. The limited magnetic field change not only ensures the normal use of the cryogenic circulation pump, but also further reduces energy consumption. Optionally, the changing magnetic field is a linearly changing magnetic field that changes between 0-1.5T.

[0036] In one embodiment, the super leak 130 is a material with micro-nano pores. The super leak formed by the material with micro-nano pores serves as a capillary channel between the first storage part 110 and the second storage part 120, allowing only a portion of the super fluid to pass through, thereby forming a pressure difference between the first storage part 110 and the second storage part 120, ensuring that the super fluid circulates along the low-temperature circulation pump under the fountain effect.

[0037] In one embodiment, the pipe 200 is connected with a functional part 210 to achieve the required refrigeration function when the superfluid flows through the functional part 210. Specifically, the functional part 210 is a component using superfluid helium as a refrigerant, wherein the functional part 210 can be a heat exchanger, a dilution refrigeration unit or a superfluid pulse tube unit according to different refrigeration requirements to cope with different refrigeration methods. Optionally, the pipe 200 is a capillary pipe and is arranged in a reciprocating structure, thereby providing a larger contact area between the overall refrigeration system and the circulating superfluid to ensure the overall refrigeration effect.

[0038] In one embodiment, valves are provided at the connection between the two ends of the storage part 100 and the pipeline 200. Optionally, valves 220 are provided at the connection between the two ends of the pipeline 200 and the storage part 100 to control the circulation flow of the superfluid in the low-temperature circulation pump when the magnetic field is enhanced (magnetization process) and the magnetic field is weakened (demagnetization process), respectively, so as to control the overall refrigeration effect.

[0039] The present invention forms a temperature gradient region in the low-temperature circulation pump by utilizing the difference in magnetocaloric effect between paramagnetic salt and antiferromagnetic salt in a changing magnetic field, thereby utilizing the fountain effect of superfluid to realize the circulation of superfluid and achieve a large flow and continuous refrigeration effect. The principle and setting parameters of the low-temperature circulation pump of the present invention are briefly introduced below in conjunction with the accompanying drawings.

[0040] like Figure 1 As shown, the cryogenic circulating pump of the present invention first forms a closed circulation loop through a storage part 100 and a pipeline 200, wherein a superfluid is stored in the storage part 100, and the pipeline 200 is respectively connected to both ends of the storage part 100 to form a loop for the circulation of the superfluid, and a functional part 210 is arranged on the pipeline 200 to achieve heat exchange when the superfluid flows through, thereby achieving a refrigeration effect. Specifically, the functional part 210 is a component that uses superfluid helium as a refrigerant, and can be set as a heat exchanger, a dilution refrigeration unit or a superfluid pulse tube unit according to different required refrigeration methods.

[0041] In this embodiment, valves 220 are respectively provided at the connection points between the two ends of the pipeline 200 and the two ends of the storage part 100 to respectively control the flow rate of the superfluid flowing out of the two ends of the storage part 100.

[0042] Furthermore, the storage unit 100 includes a first storage unit 110 and a second storage unit 120 connected in series via a superdrain 130, and superfluid is stored in the first storage unit 110 and the second storage unit 120. The superfluid is 3 He and 4 Superfluidity in He mixed solution 4He or pure 4 Superfluidity in He 4 When it is necessary to drive a superfluid pulse tube refrigerator, the working fluid is pure He. 4 He; When it is necessary to drive a dilution refrigerator, the working fluid is selected 3 He and 4 He mixed liquid. Further, the superleak 130 is a material with micro-nano pores, and optionally, the superleak 130 is made of porous Vycorglass. Further, the first storage part 110 and the second storage part 120 are cylindrical structures, and paramagnetic salt particles and antiferromagnetic salt particles are stored in the first storage part 110 and the second storage part 120 respectively to ensure that the magnetocaloric effect between the first storage part 110 and the second storage part 120 is opposite.

[0043] In this embodiment, the first storage part 110 stores antiferromagnetic salt particles to form an antiferromagnetic salt storage part, and the second storage part 120 stores paramagnetic salt particles to form a paramagnetic salt storage part. Optionally, the void volume of the antiferromagnetic salt particles in the first storage part 110 is 30% of the volume of the entire first storage part 110, and the void volume of the paramagnetic salt particles in the second storage part 120 is 30% of the volume of the entire second storage part 120, so as to ensure that the superfluid stored in the first storage part 110 and the second storage part 120 can flow smoothly. A porous heat-resistant glass (Vic glass) with micro-nano pores is arranged between the first storage part 110 and the second storage part 120 as the super leak 130 to ensure that only superfluid can flow between the first storage part 110 and the second storage part 120 through the super leak 130, so as to ensure that the superfluid flows through the super leak 130 when a temperature gradient is formed between the first storage part 110 and the second storage part 120, and a pressure difference is formed between the first storage part 110 and the second storage part 120, thereby forming a fountain effect to realize the circulation of the superfluid in the low-temperature circulation pump.

[0044] In this embodiment, the magnet 300 is a superconducting magnetic coil, and the magnet 300 surrounds the first storage part 110 and the second storage part 120 at the same time to apply the same linearly changing magnetic field to the first storage part 110 and the second storage part 120. The linearly changing magnetic field can prevent the temperature difference between the first storage part 110 and the second storage part 120 from changing abruptly. At the same time, since the magnetocaloric effect between the first storage part 110 and the second storage part 120 is opposite, the magnet 300 only needs a smaller changing magnetic field to form the required temperature gradient between the first storage part 110 and the second storage part 120, so a smaller superconducting magnetic coil can be used, thereby reducing the use of the magnet 300, reducing costs and making the structure of the low-temperature circulation pump more compact, and it can both heat up and cool down, and the formed temperature gradient is larger than that of a single heating process, and the working performance is stronger.

[0045] In this embodiment, the superfluid is a mixture 3 He and 4 He superfluid helium, further, the initial superfluid helium 3 The concentration of He is 3%. The relationship between the pressure and temperature of the superfluid helium in the cryogenic circulation pump is:

[0046]

[0047] Where P is the pressure of superfluid helium, T is the current temperature of superfluid helium, Δ1, Δ2, A, B, C and V are all constants, where Δ1 = 8.65 K, Δ2 = 15.7 K, A = 23.2 J / mol, B = 6.75×10 -6 J / molK 4 , C=500J / mol, V=27.58×10 -6 m 3 / mol.

[0048] In this way, the temperature required for the superfluid helium to achieve the required pressure and fountain effect can be determined by calculation, thereby determining the changing magnetic field provided by the magnet 300 for the first storage section 110 and the second storage section 120, thereby more effectively achieving the circulation of the superfluid helium in the low-temperature circulation pump and providing a large-flow and continuous refrigeration effect.

[0049] The working process of the low temperature circulation pump described in this embodiment is as follows:

[0050] like Figure 2As shown, the bottom (black) is the curve of magnetic field intensity change, the top (blue) is the curve of temperature change of paramagnetic salt with magnetic field intensity, and the middle (red) is the curve of temperature change of antiferromagnetic salt with magnetic field intensity. Therefore, in the low-temperature circulating pump of the present invention, when the magnet 300 applies a gradually linearly increasing magnetic field to the first storage part 110 and the second storage part 120, as the magnetization process proceeds, the overall magnetic field intensity increases. Due to the magnetocaloric effect, the temperature of the paramagnetic salt in the second storage part 120 increases and the temperature of the antiferromagnetic salt in the first storage part 110 decreases, and a temperature gradient is generated between the first storage part 110 and the second storage part 120. The temperature of the superfluid helium in the second storage part 120 is greater than that of the superfluid helium in the first storage part 110. The temperature of the helium increases, so the concentration of superfluid helium in the second storage section 120 decreases, a chemical potential difference is formed between the superfluid helium in the second storage section 120 and the superfluid helium in the first storage section 110, and the superfluid helium in the first storage section 110 moves to the second storage section 120 through the super leak 130, so that the pressure in the second storage section 120 increases, so that the superfluid helium in the second storage section 120 flows out through the pipeline 200, passes through the functional section 210 and enters the first storage section 110, so that the superfluid helium in the low temperature circulation pump When the magnet 300 applies a gradually linearly decreasing magnetic field to the first storage section 110 and the second storage section 120, as the demagnetization process proceeds, the overall magnetic field strength decreases. Due to the magnetocaloric effect, the temperature of the paramagnetic salt in the second storage section 120 decreases and the temperature of the antiferromagnetic salt in the first storage section 110 increases, resulting in a temperature gradient between the first storage section 110 and the second storage section 120. The temperature of the superfluid helium in the first storage section 110 is greater than that in the second storage section 120. The concentration of superfluid helium in the first storage section 110 decreases, and a chemical potential difference is formed between the superfluid helium in the first storage section 110 and the superfluid helium in the second storage section 120. The superfluid helium in the second storage section 120 moves to the first storage section 110 through the super leak 130, so that the pressure in the first storage section 110 increases, so that the superfluid helium in the first storage section 110 flows out through the pipeline 200, passes through the functional section 210, and enters the second storage section 120, thereby realizing the circulation of the superfluid helium in the low-temperature circulation pump.

[0051] In this way, the low-temperature circulation pump of the present invention forms an alternating heating and cooling process on the first storage part 110 and the second storage part 120 through pulsed magnetic field changes, thereby forming a larger temperature gradient than a single heating process, providing stronger working performance, and ensuring that the low-temperature circulation pump of the present invention can achieve a large flow and continuous refrigeration effect.

[0052] Furthermore, based on the above-mentioned low-temperature circulation pump, the present invention also provides a low-temperature circulation refrigeration system, which includes any low-temperature circulation pump as described above, and a space or object to be refrigerated that forms heat exchange with the low-temperature circulation pump.

[0053] In summary, the present invention discloses a low-temperature circulation pump and a low-temperature circulation refrigeration system, wherein the low-temperature circulation pump comprises: a storage part, wherein the storage part comprises a first storage part and a second storage part connected in series through a superdrain to store a superfluid, and the first storage part and the second storage part are a paramagnetic salt storage part and an antiferromagnetic salt storage part, respectively; a pipeline, wherein the pipeline connects the two ends of the storage part, so that the superfluid moves along the pipeline to achieve heat exchange; and a magnet, wherein the magnet is arranged on the outside of the first storage part and the second storage part, and provides a variable magnetic field for the first storage part and the second storage part, and forms a temperature difference between the first storage part and the second storage part through the magnetocaloric effect, so as to realize the circulation flow of the superfluid in the low-temperature circulation pump. The present invention circulates the superfluid through the magnetocaloric effect of paramagnetic salt and antiferromagnetic salt, and the superfluid always remains in a liquid state during the process, thereby realizing a large flow and continuous refrigeration cycle.

[0054] The embodiments described above are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, it should be understood by those skilled in the art that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features therein may be replaced by equivalents. However, these modifications or replacements do not deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should be included in the protection scope of the present invention.

Claims

1. A low temperature circulation pump, characterized in that: include: A storage part, the storage part comprises a first storage part and a second storage part connected in series through a superdrain to store superfluid, and the first storage part and the second storage part are a paramagnetic salt storage part and an antiferromagnetic salt storage part respectively; A pipeline, wherein the pipeline connects two ends of the storage part so that the superfluid moves along the pipeline to achieve heat exchange; A magnet is arranged on the outside of the first storage part and the second storage part, providing a changing magnetic field for the first storage part and the second storage part, forming a temperature difference between the first storage part and the second storage part through a magnetocaloric effect, and realizing the circulation of the superfluid in the low-temperature circulation pump.

2. The cryogenic circulation pump according to claim 1, characterized in that: The superfluid is 3 He and 4 Superfluidity in He mixed solution 4 He or pure 4 Superfluidity in He 4 He.

3. The cryogenic circulation pump according to claim 1, characterized in that: The first storage portion and the second storage portion are cylindrical structures.

4. The cryogenic circulation pump according to claim 3, characterized in that: One of the first storage section and the second storage section stores paramagnetic salt particles and the superfluid to form the paramagnetic salt storage section, and the other stores antiferromagnetic salt particles and the superfluid to form the antiferromagnetic salt storage section.

5. The cryogenic circulation pump according to claim 1, characterized in that: The magnet is a superconducting magnetic coil surrounding the first storage portion and the second storage portion.

6. The cryogenic circulation pump according to claim 5, characterized in that: The magnet provides a linearly changing magnetic field to the first storage portion and the second storage portion.

7. The cryogenic circulation pump according to claim 1, characterized in that: The super porous material is a material with micro-nano pores.

8. The cryogenic circulation pump according to claim 1, characterized in that: The pipeline connection is provided with a functional part, which is a component using superfluid helium as a refrigerant, including a heat exchanger, a dilution refrigeration unit or a superfluid pulse tube unit.

9. The cryogenic circulation pump according to claim 1, characterized in that: Valves are provided at the connection points between the two ends of the storage part and the pipeline.

10. A low temperature cycle refrigeration system, characterized in that: It comprises a low-temperature circulation pump as described in any one of claims 1 to 9.

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