Dilution refrigeration system adopting modularized parallel connection

Abstract

The invention provides a dilution refrigeration system adopting modularized parallel connection, and relates to the technical field of mK-level dilution refrigeration, the dilution refrigeration system comprises a plurality of dilution refrigeration units and a transmission pump set, the plurality of dilution refrigeration units share one transmission pump set, and each dilution refrigeration unit is characterized in that a 3He concentration phase and a 3He dilution phase are stored in a mixing chamber; the evaporation chamber is communicated with a 3He dilution phase and is used for separating 3He steam from the 3He dilution phase; the gas flow adjusting device is connected between the evaporation chambers and the transmission pump set, the transmission pump set extracts at least one part of 3He steam in each evaporation chamber, and the gas flow adjusting device partially receives the 3He steam output from the transmission pump set and at least partially liquefies the 3He steam received from the transmission pump set to form 3He fluid flowing back to the mixing chamber; the multiple gas flow adjusting devices of the multiple dilution refrigeration units adjust the pipe diameters of the respective gas pipelines correspondingly, so that the 3He fluid flowing back to the mixing chambers of the multiple dilution refrigeration units is subjected to the same resistance.

Description

Technical Field

[0001] The present invention relates to the technical field of mK-class dilution refrigeration, and more specifically, to a modular parallel dilution refrigeration system. Background Art

[0002] A dilution refrigerator is a refrigerator that uses helium-3 ( 3 He) and helium-4 ( 4 He) mixed liquid phase separation characteristics to achieve extremely low temperature refrigeration equipment. In order to maintain continuous refrigeration, the dilution refrigerator separates the dilution phase entering the mixing chamber by distillation and other methods. 3 He atoms are re-extracted and circulated back to the mixing chamber, forming a continuous refrigeration cycle. By optimizing the design and operating conditions, the dilution refrigerator can achieve an extremely low temperature environment as low as a few mK. Dilution refrigerators are widely used in extremely low temperature experimental research in the fields of condensed matter physics, quantum computing, astrophysics, etc. due to their advantages such as high efficiency, stability, and vibration-free. In recent years, with the rapid development of quantum information science, dilution refrigerators, as key equipment for realizing and maintaining the extremely low temperature environment required for quantum bit superconducting circuits, have received increasing attention and research.

[0003] At present, the ultra-low temperature refrigeration power of common dilution refrigerators is usually in the order of hundreds of microwatts. However, with the continuous development of use scenarios such as quantum technology, expanding the refrigeration power of dilution refrigerators has become a technical problem that needs to be solved urgently. Summary of the invention

[0004] In order to solve at least one of the technical problems in the prior art, an embodiment of the present invention provides a dilution refrigeration system using modular parallel connection, which can increase the refrigeration power of the dilution refrigeration unit.

[0005] The present invention provides a modular parallel dilution refrigeration system, comprising a plurality of dilution refrigeration units and a transmission pump group, wherein the plurality of dilution refrigeration units are arranged in a vacuum chamber, the plurality of dilution refrigeration units share the transmission pump group, and each of the dilution refrigeration units comprises: a mixing chamber, wherein the mixing chamber stores a liquid located at an upper layer; 3 The He-concentrated phase and the lower 3 He dilution phase; evaporation chamber, and the mixing chamber 3 He dilution is connected, the above evaporation chamber is used to 3 He is separated from the dilute phase 3 He steam; a gas flow regulating device connected between the evaporation chamber and the transmission pump group, the transmission pump group extracts at least a portion of each of the evaporation chambers 3 He steam, the gas flow regulating device partially receives the gas output from the transmission pump group 3He steam, and receive from the above transfer pump group 3 The He vapor is at least partially liquefied to form a 3 wherein the plurality of gas flow regulating devices of the plurality of dilution refrigeration units adjust the diameters of their respective gas pipelines so that the gas flows back to the mixing chambers of the plurality of dilution refrigeration units respectively; 3 The resistance encountered by the fluid is the same.

[0006] Optionally, the plurality of evaporation chambers of the plurality of dilution refrigeration units are connected to the one transmission pump group via a gas transmission pipeline, so that the transmission pump group can transfer at least a portion of each of the evaporation chambers. 3 And steam is extracted.

[0007] Optionally, the gas flow regulating device is detachably connected between the evaporation chamber and the transmission pump assembly, so as to facilitate replacement of the next gas flow regulating device after adjusting the diameter of the gas pipeline once.

[0008] Optionally, the gas flow regulating device comprises: a supporting body; a gas pipeline, which is configured to be coiled around the outside of the supporting body in the height direction of the supporting body, and the gas pipeline is used to receive the gas received from the transmission pump group; 3 He steam is at least partially throttled and liquefied based on the Joule-Thomson effect to form the above 3 He fluid; an extrusion assembly, arranged on the outside of the gas pipeline, the extrusion assembly being configured to, when driven by an external force, squeeze the gas pipeline along the width direction of the support body to reduce the diameter of the gas pipeline, thereby regulating the gas flowing back to the mixing chamber 3 And the resistance of the fluid.

[0009] Optionally, two surfaces of the support body close to the extrusion assembly are respectively provided with extrusion surfaces, and the two extrusion surfaces are configured to have recesses respectively, and the two recesses provide space for the extrusion assembly to extrude the gas pipeline.

[0010] Optionally, the extrusion assembly includes: two first rod portions, which are respectively arranged on the outsides of the two recesses, and the two first rod portions extend along the height direction of the support body; two second rod portions, which respectively pass through the two ends of the two first rod portions along the width direction of the support body to limit the support body between the two first rod portions; two first limiting members, which are respectively arranged at one end of the two second rod portions; and two second limiting members, which are respectively rotatably arranged at the other ends of the two second rod portions to respectively adjust the positions of the two second rod portions between the two ends of the two first rod portions.

[0011] Optionally, through holes are provided at opposite ends of the two first rod portions to allow the second rod portion to pass through.

[0012] Optionally, the two second limit members are nuts, and the two second rod portions are each provided with a threaded portion, and the two nuts are respectively threadedly engaged with the two threaded portions; wherein, when driven by an external force, the two nuts drive the two first rod portions to approach each other, so as to squeeze the gas pipeline along the width direction of the support body, thereby reducing the diameter of the gas pipeline.

[0013] Optionally, the above-mentioned mixing chamber 3 The He-enriched phase is configured to respond to the above 3 He dilution phase 3 The concentration of He decreases to the above 3 He dilution phase compensation 3 At the same time, it absorbs the surrounding heat to perform cooling.

[0014] Optionally, each of the dilution refrigeration units further comprises: a multi-stage heat exchange assembly, each stage of the heat exchange assembly comprising a first side and a second side, the first side being used to communicate with the mixing chamber. 3 He dilution phase and the evaporation chamber, the second side is used for the 3 He fluid flows back to the above-mentioned mixing chamber 3 The He concentrated phase is used for heat exchange with the first side.

[0015] According to an embodiment of the present invention, a modular parallel dilution refrigeration system includes a plurality of dilution refrigeration units and a transmission pump group. The plurality of dilution refrigeration units are arranged in a vacuum chamber. The plurality of dilution refrigeration units share a transmission pump group. Each dilution refrigeration unit includes a mixing chamber, an evaporation chamber and a gas flow regulating device. The mixing chamber stores gas located at the upper layer. 3 The He-concentrated phase and the lower 3 He dilution phase, evaporation chamber and mixing chamber 3 He dilution is connected, and the evaporation chamber is used to 3 He is separated from the dilute phase 3 He steam, gas flow control device is connected between the evaporation chamber and the transmission pump group, and the transmission pump group extracts at least a part of each evaporation chamber 3 He steam and gas flow control device partially receives the output from the transmission pump group 3 He steam and transfer the 3 The He vapor is at least partially liquefied to form a 3The multiple gas flow regulating devices of the multiple dilution refrigeration units adjust the diameters of their respective gas pipelines so that the gas flows back to the mixing chambers of the multiple dilution refrigeration units. 3 The He fluid is subject to the same resistance, which can increase the cooling power of the dilution refrigeration unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a side view of two dilution refrigeration units and a transmission pump group connected in parallel according to an embodiment of the present invention;

[0017] Figure 2 is a perspective view of two dilution refrigeration units connected in parallel according to an embodiment of the present invention;

[0018] Figure 3 is a first perspective stereoscopic diagram of a gas flow regulating device according to an embodiment of the present invention;

[0019] Figure 4 is a second perspective stereoscopic diagram of a gas flow regulating device according to an embodiment of the present invention;

[0020] Figure 5 is a side view of a gas flow regulating device according to an embodiment of the present invention;

[0021] Figure 6 yes Figure 5 Cross-section view along the AA direction.

[0022] In the accompanying drawings, the meanings of the reference numerals are as follows:

[0023] 1. Vacuum chamber;

[0024] 100. Dilution refrigeration unit;

[0025] 2. Mixing chamber;

[0026] 3. Evaporation chamber;

[0027] 4. Heat exchange components;

[0028] 5. Gas transmission pipeline;

[0029] 6. Transmission pump set;

[0030] 7. Gas flow regulating device;

[0031] 101, support body;

[0032] 102. Gas pipelines;

[0033] 103, first rod portion;

[0034] 104, second rod portion;

[0035] 105. A first limiting member;

[0036] 106. A second limiting member. DETAILED DESCRIPTION

[0037] Below, embodiments of the present invention will be described with reference to the accompanying drawings. However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present invention. In the following detailed description, for ease of explanation, many specific details are set forth to provide a comprehensive understanding of embodiments of the present invention. However, it is apparent that one or more embodiments may also be implemented without these specific details. In addition, in the following description, descriptions of known structures and technologies are omitted to avoid unnecessary confusion of concepts of the present invention.

[0038] The terms used herein are only for describing specific embodiments and are not intended to limit the present invention. The terms "comprise", "include", etc. used herein indicate the existence of the features, steps, operations and / or components, but do not exclude the existence or addition of one or more other features, steps, operations or components.

[0039] All terms (including technical and scientific terms) used herein have the meanings commonly understood by those skilled in the art unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification and should not be interpreted in an idealized or overly rigid manner.

[0040] In the case of using expressions such as "at least one of A, B, and C, etc.", it should generally be interpreted in accordance with the meaning of the expression generally understood by those skilled in the art (for example, "a system having at least one of A, B, and C" should include but is not limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc.). In the case of using expressions such as "at least one of A, B, or C, etc.", it should generally be interpreted in accordance with the meaning of the expression generally understood by those skilled in the art (for example, "a system having at least one of A, B, or C" should include but is not limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc.).

[0041] In order to solve the problem of low refrigeration power of a single dilution refrigeration unit, according to an inventive concept of one aspect of the present invention, a modular parallel dilution refrigeration system includes a plurality of dilution refrigeration units and a transmission pump group, the plurality of dilution refrigeration units are arranged in a vacuum chamber, the plurality of dilution refrigeration units share a transmission pump group, each dilution refrigeration unit includes a mixing chamber, an evaporation chamber and a gas flow regulating device, the mixing chamber stores gas located at the upper layer3 The He-concentrated phase and the lower 3 He dilution phase, evaporation chamber and mixing chamber 3 He dilution is connected, and the evaporation chamber is used to 3 He is separated from the dilute phase 3 He steam, gas flow control device is connected between the evaporation chamber and the transmission pump group, and the transmission pump group extracts at least a part of each evaporation chamber 3 He steam and gas flow control device partially receives the output from the transmission pump group 3 He steam and receives it from the transfer pump group 3 The He vapor is at least partially liquefied to form a 3 The multiple gas flow regulating devices of the multiple dilution refrigeration units adjust the diameters of their respective gas pipelines so that the gas flows back to the mixing chambers of the multiple dilution refrigeration units. 3 The He fluid is subject to the same resistance, which can increase the cooling power of the dilution refrigeration unit.

[0042] According to an embodiment of the present invention, a modular parallel dilution refrigeration system is provided, which includes a plurality of dilution refrigeration units and a transmission pump group. The plurality of dilution refrigeration units are arranged in a vacuum chamber, and the plurality of dilution refrigeration units share a transmission pump group. Each dilution refrigeration unit includes a mixing chamber, an evaporation chamber, and a gas flow regulating device. The mixing chamber stores the gas located at the upper layer. 3 The He-concentrated phase and the lower 3 He dilution phase. 3 He dilution is connected, and the evaporation chamber is used to 3 He is separated from the dilute phase 3 The gas flow regulating device is connected between the evaporation chamber and the transmission pump group, and the transmission pump group extracts at least a portion of each evaporation chamber. 3 He steam and gas flow control device partially receives the output from the transmission pump group 3 He steam and receives it from the transfer pump group 3 He vapor is at least partially liquefied and is separated from the unliquefied 3 He mixed to form a flow back to the mixing chamber 3 The multiple gas flow control devices of the multiple dilution refrigeration units adjust the diameters of their respective gas pipelines so that the gas flowing back to the mixing chambers of the multiple dilution refrigeration units is 3 The resistance encountered by the fluid is the same.

[0043] According to an embodiment of the present invention, in the dilution refrigeration unit, mainly using 3 He and 4 He mixed working fluid for refrigeration, when 3 He and4 When the He mixture is below 0.86K, it will separate into two phases. The upper phase is the concentrated phase, and its main components are 3 He, that is 3 He solution. The lower layer is the dilute phase, the main components are 3 He and 4 He mixture, where 3 He accounts for about 6.4%~6.6%.

[0044] According to an embodiment of the present invention, the liquid flowing back into the mixing chamber of the dilution refrigeration unit 3 The resistance factors of He fluid include pipeline resistance, gravity, flow resistance inside heat exchange components, etc. Pipeline resistance is due to 3 The He fluid needs to pass through the pipe when it flows back to the mixing chamber. The friction, bends and cross-sectional changes of the inner wall of the pipe will cause flow resistance. The gravity factor is 3 When He fluid flows from room temperature back to the mixing chamber, it needs to overcome gravity (especially when the mixing chamber is located at a lower position), which will increase the flow resistance. The flow resistance factor inside the heat exchange component is 3 When the He fluid flows back to the mixing chamber, it needs to pass through multiple stages of heat exchange components to reduce the temperature. The internal structure of the heat exchange components will increase the flow resistance. 3 When He vapor flows back to the mixing chamber, it will be partially liquefied to form a gas-liquid two-phase flow, and the flow resistance of the gas-liquid two-phase flow will be greater than that of the single-phase flow.

[0045] Figure 1 is a side view of two dilution refrigeration units and a transmission pump group connected in parallel according to an embodiment of the present invention, Figure 2 is a perspective view of two dilution refrigeration units connected in parallel according to an embodiment of the present invention.

[0046] According to an embodiment of the present invention, a modular parallel dilution refrigeration system includes a plurality of dilution refrigeration units 100 and a transmission pump group 6. The plurality of dilution refrigeration units are arranged in a vacuum chamber 1. The plurality of dilution refrigeration units 100 share a transmission pump group 6. The plurality of dilution refrigeration units 100 may be two, three, four, etc. Taking two dilution refrigeration units 100 as an example, Figure 1 and Figure 2 As shown, when two adjacent dilution refrigeration units 100 are connected in parallel, a common transmission pump group 6 is required to make the mixing chambers 2 of the two dilution refrigeration units 100 flow back to the mixing chambers 2 of the two dilution refrigeration units 100. 3The resistance of He fluid is the same. A gas flow regulating device 7 is arranged between the evaporation chambers 3 of the two dilution refrigeration units 100 and the common transmission pump group 6. By adjusting the pipe diameters of the two gas flow regulating devices 7, the flow resistance of the fluid flowing through the gas pipelines 102 of the two gas flow regulating devices 7 is made the same, that is, at least a part of the fluid drawn from each evaporation chamber 3 through the transmission pump group 6 is 3 Half of the He vapor passes through the gas flow control device 7 between the evaporation chamber 3 on one side and the common transmission pump group 6, and the liquefied and unliquefied He vapor are at least partially throttled. 3 He mixed to form 3 He fluid, after 3 He fluid flows back to the mixing chamber 2, 3 The other half of the He vapor is at least partially throttled between the liquefied and unliquefied gas through the gas flow control device 7 between the evaporation chamber 3 on the other side and the common transmission pump group 6. 3 He mixed to form 3 He fluid, after 3 The He fluid flows back to the mixing chamber 2. The He fluid flows back to the mixing chamber 2 of the two dilution refrigeration units 100. 3 The He fluid is subjected to the same resistance, which can ensure the two dilution refrigeration units 100 3 The He fluid refluxes evenly, avoiding flow imbalance caused by uneven resistance, making the operation more stable. Moreover, the parallel connection makes 3 The total flow of He increases, more 3 He participates in the refrigeration cycle, saving expensive 3 He, improved the cooling efficiency. 3 The increase in the total flow rate of He and the balance of the reflux resistance also improve the efficiency of heat exchange and enhance the refrigeration effect. At the same time, connecting two dilution refrigeration units 100 in parallel reduces the load of a single dilution refrigeration unit 100, reduces the risk of failure, and improves reliability.

[0047] According to an embodiment of the present invention, in order to further expand the refrigeration power, the dilution refrigeration unit 100 can be flexibly added to achieve the most reasonable efficiency ratio and avoid the increase of invalid power while meeting the requirements of the refrigeration power. Multiple dilution refrigeration units 100 can share a transmission pump group 6, which can reduce the number of external transmission pump groups 6, reduce the difficulty of the control system, and further reduce the cost. At the same time, the operator can replace or remove a dilution refrigeration unit 100 among the multiple dilution refrigeration units 100 separately, which provides greater convenience for subsequent maintenance and adjustment of the refrigeration power.

[0048] According to an embodiment of the present invention, the mixing chamber 2 3 The He-enriched phase is configured to respond to 3 He dilution phase 3The concentration of He decreases to 3 He dilution phase compensation 3 At the same time, it absorbs the surrounding heat to perform cooling.

[0049] According to an embodiment of the present invention, the mixing chamber 2 stores 3 He concentrated phase (i.e. 3 He solution) and 3 He dilution phase (i.e. 3 He and 4 He mixture), when the evaporation chamber 3 reaches the preset temperature, about 0.6K~1K (Kelvin), generally 0.8K, 3 The saturated vapor pressure of He is significantly higher than 4 He is thus selectively evaporated. 3 The He concentration decreases accordingly, and the 3 The He dilute phase will replenish the evaporation chamber 3 3 He, thereby making the mixing chamber 2 3 He in concentrated phase 3 Direction 3 He dilutes and dissolves, when 3 When He passes through the phase interface, it absorbs the surrounding heat, and the temperature of the mixing chamber 2 and the surrounding cold plate drops, achieving dilution refrigeration. 3 He is selectively evaporated to become 3 He steam, through the transmission pump group 6 (including vacuum pump, compressor, etc.) 3 He vapor is drawn out of the evaporation chamber 3, pressurized and then refluxed. In order to make the dilution refrigeration continuous and cyclic, 3 The He steam is at least partially throttled and decompressed by the gas flow control device 7 and then liquefied and separated from the unliquefied He steam. 3 He mixed to form 3 He fluid, and then flows back to the mixing chamber 2 3 He concentrates the phase and then passes through the phase interface where the concentrated phase and the dilute phase separate, thus performing dilution refrigeration in a cycle.

[0050] According to an embodiment of the present invention, multiple evaporation chambers 3 of multiple dilution refrigeration units 100 are connected to a transmission pump group 6 through a gas transmission pipeline 5, so that the transmission pump group 6 can transfer at least a portion of each evaporation chamber 3. 3 And steam is extracted.

[0051] According to the embodiment of the present invention, a plurality of dilution refrigeration units 100 share one transmission pump set 6, which can reduce the number of external transmission pump sets 6, reduce the difficulty of the control system, and further reduce the cost.

[0052] Figure 3is a first perspective stereogram of a gas flow regulating device according to an embodiment of the present invention, Figure 4 It is a second perspective stereoscopic image of a gas flow regulating device according to an embodiment of the present invention.

[0053] According to an embodiment of the present invention, Figure 3 and Figure 4 As shown, the gas flow regulating device 7 is detachably connected between the evaporation chamber 3 and the transmission pump group 6, so as to facilitate replacement of the next gas flow regulating device 7 after adjusting the diameter of the gas pipeline 102 once.

[0054] According to an embodiment of the present invention, if the output from the transmission pump group 6 is to be 3 To adjust the He steam flow rate at different levels, the gas flow device 7 can be removed and replaced with a new gas flow device 7, and the gas pipeline 102 can be re-extruded along the width direction of the support body 101 to adjust the diameter of the gas pipeline 102, thereby adjusting the 3 The flow rate of He fluid flowing through the gas pipeline 102 is adjusted by 3 The flow rate of He fluid is increased to match the dilution refrigeration unit 100, expand its performance limit, and lay a good foundation for further development of the dilution refrigeration unit 100.

[0055] According to an embodiment of the present invention, Figure 3 and Figure 4 As shown, the gas flow regulating device 7 includes a support body 101, a gas pipeline 102 and an extrusion assembly. The gas pipeline 102 is configured to be coiled on the outside of the support body 101 in the height direction of the support body 101, and the gas pipeline 102 is used to receive the gas from the transmission pump group 6. 3 He steam is at least partially throttled by the Joule-Thomson effect after liquefaction and before liquefaction. 3 He mixed to form 3 The extrusion assembly is arranged outside the gas pipeline 102, and is configured to, when driven by an external force, squeeze the gas pipeline 102 along the width direction of the support body 101 to reduce the diameter of the gas pipeline 102, thereby adjusting the gas flowing back to the mixing chamber 2. 3 And the resistance of the fluid.

[0056] According to an embodiment of the present invention, the 3 When the He steam passes through the gas pipeline 102, the extrusion assembly is driven by an external force to squeeze the gas pipeline 102 along the width direction of the support body 101, and the diameter of the gas pipeline 102 is reduced. 3 When He steam flows through gas pipeline 102, the pressure drops. 3 He vapor undergoes the Joule-Thomson effect due to 3The interatomic forces of He atoms are close to the ideal gas level. 3 The inversion temperature of He is extremely low, about 40K (-233℃). When the gas expands, the change in the force between atoms causes the change in internal energy, which in turn causes the temperature change. When the temperature is greater than 40K, the Joule-Thomson coefficient is negative. 3 When He is throttled, the temperature rises. When the temperature is less than 40K, the Joule-Thomson coefficient is positive. 3 When throttling occurs, the temperature drops. 3 He vapor is at least partially liquefied and is separated from the unliquefied 3 He mixed to form 3 and fluid.

[0057] According to an embodiment of the present invention, the height direction of the support body 101 is Figure 4 The Z direction shown in FIG. 1 is the width direction of the support body 101. Figure 4 The X direction shown in FIG. 1 is the length direction of the support body 101. Figure 4 Y direction shown in .

[0058] According to an embodiment of the present invention, the gas pipeline 102 is coiled on the outside of the support body 101 in the height direction of the support body 101, and the gas pipeline 102 is used to receive the gas from the transmission pump group 6. 3 He steam is at least partially throttled by the Joule-Thomson effect after liquefaction and before liquefaction. 3 He mixed to form 3 He fluid, the extrusion assembly is arranged on the outside of the gas pipeline 102, and the extrusion assembly is driven by an external force to extrude the gas pipeline 102 along the width direction of the support body 101. The gas flow regulating device 7 is suitable for the extremely low temperature working environment of the dilution refrigeration unit 100, and can flexibly adjust the diameter of the gas pipeline 102, thereby adjusting the gas flowing back to the mixing chamber 2. 3 The resistance to He fluid is small, and it is simple to make, highly reliable in use and has a wide adjustable range.

[0059] According to an embodiment of the present invention, two surfaces of the support body 101 close to the extrusion assembly are respectively provided with extrusion surfaces, and the two extrusion surfaces are configured to have recesses respectively, and the two recesses provide space for the extrusion assembly to extrude the gas pipeline 102 .

[0060] According to an embodiment of the present invention, the two recesses provide necessary space for the extrusion assembly to extrude the gas pipeline 102, ensuring that the extrusion process proceeds smoothly, avoiding direct contact between the extrusion assembly and the support body 101, reducing mechanical interference and wear, extending the service life of the gas pipeline 102, and facilitating subsequent maintenance and replacement. The two recesses also make the extrusion pressure evenly distributed on the gas pipeline 102 along the height direction of the support body 101, preventing local stress concentration, providing protection for the gas pipeline 102, and uniform force improves the stability of the extrusion process, ensuring the consistency of the extrusion effect of the gas pipeline 102 in the height direction of the support body 101. In addition, the two extrusion surfaces have recesses respectively, which can adapt to gas pipelines 102 of different sizes, improve flexibility, and enhance the versatility of the gas flow regulating device 7.

[0061] According to an embodiment of the present invention, the extrusion assembly includes two first rods 103, two second rods 104, two first stoppers 105 and two second stoppers 106. The two first rods 103 are respectively arranged on the outside of the two recesses, and the two first rods 103 extend along the height direction of the support body 101. The two second rods 104 pass through the two ends of the two first rods 103 along the width direction of the support body 101, so as to limit the support body 101 between the two first rods 103. The two first stoppers 105 are respectively arranged at one end of the two second rods 104. The two second stoppers 106 are respectively rotatably arranged at the other ends of the two second rods 104, so as to adjust the positions of the two second rods 104 between the two ends of the two first rods 103.

[0062] According to an embodiment of the present invention, the two second stoppers 106 are driven by external force to adjust the positions of the two second rods 104 between the two ends of the two first rods 103, and a flow detection device can be connected to the gas pipeline 102. 3 The flow rate of He steam flowing through the gas pipeline 102 is used to obtain the deformation caused by the two first rods 103 exerting a squeezing force on the gas pipeline 102. The applied external force is, for example, 10N, and the pressure of the gas pipeline 102 is 0.2 MPa. 3 The flow rate of He steam flowing through the gas pipeline 102 is 20 ml / min.

[0063] Figure 5 is a side view of a gas flow regulating device according to an embodiment of the present invention, Figure 6 yes Figure 5 Cross-section view along the AA direction.

[0064] According to an embodiment of the present invention, Figure 5 and Figure 6As shown, through holes are formed at opposite ends of the two first rod portions 103 to allow the second rod portion 104 to pass through.

[0065] According to the embodiment of the present invention, one second rod 104 passes through the through holes opened at both ends (on the same side) of the two first rods 103, and the other second rod 104 passes through the through holes opened at both ends of the two first rods 103, which can effectively connect the two first rods 103, improve stability and rigidity, and the two second rods 104 are easy to install and disassemble, which is convenient for subsequent maintenance and replacement. The through holes can ensure the precise alignment of the two first rods 103 and the second rods 104, and improve the installation accuracy.

[0066] According to an embodiment of the present invention, the two second stoppers 106 are nuts, and the two second rods 104 are both provided with threaded portions, and the two nuts are respectively threadedly engaged with the two threaded portions. When driven by an external force, the two nuts drive the two first rods 103 to approach each other, so as to squeeze the gas pipeline 102 along the width direction of the support body 101, so that the diameter of the gas pipeline 102 is reduced.

[0067] According to the embodiment of the present invention, two nuts are respectively threadedly engaged with two threaded parts, and when driven by external force, the two nuts drive one first rod part 103 to slide on the two second rod parts 104, and approach the other first rod part 103 to squeeze the gas pipeline 102 along the width direction of the support body 101, so that the diameter of the gas pipeline 102 is reduced. The two second rod parts 104 are both provided with threaded parts, which provide greater freedom of movement for the sliding of the first rod part 103, and a wide adjustable range.

[0068] According to an embodiment of the present invention, by changing the number of turns of the gas pipeline 102 wound around the outer side of the support body 101 in the height direction of the support body 101, the adjustable range of the gas flow is further expanded, and the number of turns can be 5 turns, 6 turns, 7 turns, etc.

[0069] According to an embodiment of the present invention, the cross section of the support body 101 in a plane perpendicular to the height direction is any one of opposing horseshoes, ellipses, trapezoids and squares.

[0070] According to an embodiment of the present invention, if the cross-section of the support body 101 in a plane perpendicular to the height direction is an opposed horseshoe or opposed ellipse, the arc-shaped structure can effectively disperse stress, reduce stress concentration, and extend the life of the support body 101. It can also better fit with the gas pipeline 102 and improve space utilization. If the cross-section of the support body 101 in a plane perpendicular to the height direction is an opposed trapezoid or an opposed square, the trapezoid and the square are wider than the horseshoe or the ellipse, and can provide good support and stability for the gas pipeline 102.

[0071] According to an embodiment of the present invention, the material of the support body 101 is any one of stainless steel, titanium alloy and nickel alloy.

[0072] According to an embodiment of the present invention, if the material of the support body 101 is stainless steel, the stainless steel can maintain good toughness and strength in an extremely low temperature working environment, and also has good corrosion resistance and low cost. If the material of the support body 101 is titanium alloy, the titanium alloy can maintain good toughness and strength in an extremely low temperature working environment, and the thermal conductivity of the titanium alloy is low, which can reduce heat conduction and maintain the ambient temperature. At the same time, the titanium alloy has low density but high strength, which helps to reduce the overall weight and maintain structural strength. If the material of the support body 101 is nickel alloy, the nickel alloy can maintain excellent toughness and strength in an extremely low temperature working environment, and the nickel alloy has excellent corrosion resistance.

[0073] According to an embodiment of the present invention, each dilution refrigeration unit 100 further includes a multi-stage heat exchange assembly 4. Each stage of the multi-stage heat exchange assembly 4 includes a first side and a second side, and the first side is used to communicate with the mixing chamber 2. 3 He dilution phase and evaporation chamber 3, the second side is used for 3 He fluid flows back into the mixing chamber 2 3 The He concentrated phase is used to exchange heat with the first side.

[0074] According to an embodiment of the present invention, the first side (cold side) of each stage heat exchange component 4 is used to heat the mixing chamber 2. 3 The He dilution phase is connected to the evaporation chamber 3, when the evaporation chamber 3 reaches a preset temperature range, approximately 0.6K~1K. 3 The saturated vapor pressure of He is higher than 4 He is thus evaporated and extracted separately. 3 He concentration decreases, and the 3 The He dilute phase will be replenished to the evaporation chamber 3 through the first side flow path 3 He. The transmission pump group 6 extracts at least a portion of each evaporation chamber 3 3 He steam, each gas flow regulating device 7 of each dilution refrigeration unit 100 partially receives the gas output from the transmission pump group 6 3 He steam, and based on the Joule-Thomson effect, it will be received from the transmission pump group 6 3 He steam is at least partially throttled and condensed to form a liquefied 3 He mixed 3 He fluid and returns to the mixing chamber 2 through the second side (hot side) flow path 3 He concentrated phase, at this time 3 He in concentrated phase 3 He concentration is greater than3 He in the dilute phase 3 He concentration, so 3 He in concentrated phase 3 He will 3 He dilute phase moves, when 3 When He passes through the phase interface, it absorbs the surrounding heat, causing the temperature of the mixing chamber 2 to drop, and the dilution refrigeration cycle is repeated.

[0075] According to an embodiment of the present invention, the heat exchange component 4 includes but is not limited to a pancake-shaped radiator, whose upper and lower layers are separated by oxygen-free copper to transfer heat, or a spiral double-layer tube radiator, whose inner and outer layers are separated by a tube wall to transfer heat.

[0076] It will be appreciated by those skilled in the art that the features described in the various embodiments and / or claims of the present invention may be combined or coupled in various ways, even if such combinations or couplings are not explicitly described in the present invention. In particular, the features described in the various embodiments and / or claims of the present invention may be combined or coupled in various ways without departing from the spirit and teachings of the present invention. All such combinations and / or couplings fall within the scope of the present invention.

[0077] It should also be noted that the directional terms mentioned in the embodiments, such as "upper", "lower", "front", "back", "left", "right", etc., are only reference directions of the drawings and are not intended to limit the scope of protection of the present invention. Throughout the drawings, the same elements are represented by the same or similar reference numerals. Conventional structures or configurations will be omitted when they may cause confusion in the understanding of the present invention, and the shapes and sizes of the components in the drawings do not reflect the actual size and proportion, but only illustrate the contents of the embodiments of the present invention.

[0078] Unless otherwise indicated, the numerical parameters in this specification and the appended claims are approximate values ​​and can be changed according to the desired characteristics obtained by the content of the present invention. Specifically, all numbers used in the specification and claims to express the content of the composition, reaction conditions, etc., should be understood to be modified by the term "about" in all cases. In general, the meaning of the expression is to include changes in some embodiments of ±10%, in some embodiments of ±5%, in some embodiments of ±1%, and in some embodiments of ±0.5% by a specific number.

[0079] The ordinal numbers used in the specification and claims, such as "first", "second", "third", etc., to modify the corresponding elements, do not themselves mean that the elements have any ordinal numbers, nor do they represent the order of one element and another element, or the order in the manufacturing method. The use of these ordinal numbers is only used to clearly distinguish a component with a certain name from another component with the same name.

[0080] In addition, unless the steps are specifically described or must occur in sequence, the order of the above steps is not limited to the above list, and can be changed or rearranged according to the required design. And the above embodiments can be mixed and matched with each other or with other embodiments based on design and reliability considerations, that is, the technical features in different embodiments can be freely combined to form more embodiments.

[0081] The embodiments of the present invention are described above. However, these embodiments are only for the purpose of illustration, and are not intended to limit the scope of the present invention. Although each embodiment is described above, it does not mean that the measures in each embodiment cannot be used in combination. The scope of the present invention is defined by the attached claims and their equivalents. Without departing from the scope of the present invention, those skilled in the art may make various substitutions and modifications, which should all fall within the scope of the present invention.

Claims

1. A modular parallel dilution refrigeration system, characterized in that: It comprises a plurality of dilution refrigeration units and a transmission pump group, wherein the plurality of dilution refrigeration units are arranged in a vacuum chamber, the plurality of dilution refrigeration units share one transmission pump group, and each of the dilution refrigeration units comprises: A mixing chamber is provided in which the upper 3 The He-concentrated phase and the lower 3 He dilution phase; The evaporation chamber and the mixing chamber 3 He dilution is connected, and the evaporation chamber is used to extract 3 He is separated from the dilute phase 3 He steam; A gas flow regulating device is connected between the evaporation chamber and the transmission pump group, and the transmission pump group extracts at least a portion of each of the evaporation chambers. 3 He steam, the gas flow regulating device partially receives the gas output from the transmission pump group 3 He steam, and receives it from the transfer pump group 3 The He vapor is at least partially liquefied to form a 3 He fluid; The gas flow regulating devices of the plurality of dilution refrigeration units adjust the diameters of their respective gas pipelines so that the gas flowing back to the mixing chambers of the plurality of dilution refrigeration units is 3 The resistance encountered by the fluid is the same.

2. The modular parallel dilution refrigeration system according to claim 1, characterized in that: The plurality of evaporation chambers of the plurality of dilution refrigeration units are connected to a transmission pump group through a gas transmission pipeline, so that the transmission pump group can transfer at least a portion of each evaporation chamber. 3 And steam is extracted.

3. The modular parallel dilution refrigeration system according to claim 1, characterized in that: The gas flow regulating device is detachably connected between the evaporation chamber and the transmission pump group, so as to facilitate replacement of the next gas flow regulating device after adjusting the diameter of the gas pipeline once.

4. The modular parallel dilution refrigeration system according to claim 1, characterized in that: The gas flow regulating device comprises: Supporting the body; The gas pipeline is configured to be wound around the outside of the support body in the height direction of the support body, and the gas pipeline is used to receive the gas from the transmission pump group. 3 He steam is at least partially throttled and liquefied based on the Joule-Thomson effect to form the 3 He fluid; An extrusion assembly is arranged on the outside of the gas pipeline, and the extrusion assembly is configured to squeeze the gas pipeline along the width direction of the support body when driven by an external force to reduce the diameter of the gas pipeline, thereby adjusting the gas flowing back to the mixing chamber. 3 And the resistance of the fluid.

5. The modular parallel dilution refrigeration system according to claim 4, characterized in that: The two surfaces of the support body close to the extrusion assembly are respectively provided with extrusion surfaces, and the two extrusion surfaces are configured to have recesses respectively, and the two recesses provide space for the extrusion assembly to extrude the gas pipeline.

6. The modular parallel dilution refrigeration system according to claim 5, characterized in that: The extrusion assembly comprises: Two first rod portions are respectively arranged at the outer sides of the two recessed portions, and the two first rod portions extend along the height direction of the support body; Two second rod portions, respectively passing through two ends of the two first rod portions along the width direction of the support body, so as to restrict the support body between the two first rod portions; Two first limit members are respectively arranged at one end of the two second rod parts; The two second position-limiting members are rotatably disposed at the other ends of the two second rod portions, respectively, so as to respectively adjust the positions of the two second rod portions between the two ends of the two first rod portions.

7. The modular parallel dilution refrigeration system according to claim 6, characterized in that: Through holes are provided at opposite ends of the two first rod portions to allow the second rod portion to pass through.

8. The modular parallel dilution refrigeration system according to claim 6, characterized in that: The two second position-limiting members are nuts, the two second rod portions are both provided with threaded portions, and the two nuts are respectively threadedly coupled with the two threaded portions; Wherein, when driven by an external force, the two nuts drive the two first rod portions to approach each other, so as to squeeze the gas pipeline along the width direction of the support body, so that the diameter of the gas pipeline is reduced.

9. The modular parallel dilution refrigeration system according to claim 1, characterized in that: The mixing chamber 3 The He-enriched phase is configured to respond to the 3 He dilution phase 3 The concentration of He decreases to 3 He dilution phase compensation 3 At the same time, it absorbs the surrounding heat to perform cooling.

10. The modular parallel dilution refrigeration system according to claim 1, characterized in that: Each of the dilution refrigeration units further comprises: A multi-stage heat exchange component, each stage of the heat exchange component includes a first side and a second side, the first side is used to communicate with the 3 He dilution phase and the evaporation chamber, the second side is used for the 3 He fluid flows back into the mixing chamber 3 The He concentrated phase is heat exchanged with the first side.

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