Liquid metal electromagnetic pump

Abstract

A liquid metal electromagnetic pump includes: a pipeline portion, the pipeline portion is provided with an inlet for receiving liquid metal inflow and an outlet for conveying liquid metal outward; a coil portion, the coil portion is arranged radially outside the pipeline portion, and when the coil portion is energized, it can generate a magnetic field in the pipeline portion to drive the liquid metal to flow in the pipeline portion; a protective shell, arranged radially outside the coil portion and extending along the axial direction of the pipeline portion to cover the coil portion; a fixing portion, the fixing portion is arranged at a position close to the inlet and the outlet, and the two ends of the protective shell in the axial direction are connected to the fixing portion; a control portion, used to control the current in the coil portion, one side of the protective shell is raised to form an accommodating space, and the control portion is arranged in the accommodating space. The liquid metal electromagnetic pump according to the embodiment of the present application has a compact structure and is particularly suitable for systems with miniaturization characteristics.

Description

Technical Field

[0001] The present application relates to the technical field of electromagnetic pumps, and in particular to a liquid metal electromagnetic pump. Background Art

[0002] As a liquid metal conveying equipment, liquid metal electromagnetic pumps have been widely used, especially in the field of nuclear power, due to their advantages of no leakage, strong adjustment ability and high reliability. However, liquid metal electromagnetic pumps in the prior art are usually used in large systems. In some systems with miniaturized characteristics, such as liquid metal cooling reactor auxiliary systems or related scientific experimental devices, there is a lack of suitable liquid metal electromagnetic pumps. Summary of the invention

[0003] In view of the above problems, the present application is proposed to provide a liquid metal electromagnetic pump that overcomes the above problems or at least partially solves the above problems.

[0004] According to an embodiment of the present application, a liquid metal electromagnetic pump is provided, comprising: a pipeline portion, the pipeline portion is provided with an inlet for receiving the inflow of liquid metal and an outlet for conveying the liquid metal outward; a coil portion, the coil portion is arranged on the radially outer side of the pipeline portion, and the coil portion can generate a magnetic field in the pipeline portion when energized to drive the liquid metal to flow in the pipeline portion; a protective shell, arranged on the radially outer side of the coil portion and extending along the axial direction of the pipeline portion to cover the coil portion; a fixing portion, the fixing portion is arranged at a position close to the inlet and the outlet, and both ends of the protective shell in the axial direction are connected to the fixing portion; a control portion, used to control the current in the coil portion, one side of the protective shell is bulged to form an accommodating space, and the control portion is arranged in the accommodating space.

[0005] The liquid metal electromagnetic pump according to the embodiment of the present application has a compact structure and is particularly suitable for use in systems with miniaturization characteristics. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 is a schematic diagram of a liquid metal electromagnetic pump according to an embodiment of the present application;

[0007] Figure 2 is a schematic diagram of a first magnetic conductor according to an embodiment of the present application;

[0008] Figure 3 is a schematic diagram of a coil portion according to an embodiment of the present application;

[0009] Figure 4 is a schematic diagram of a radial cross section of a pipeline portion according to an embodiment of the present application;

[0010] Figure 5 It is a schematic axial cross-sectional view of a pipeline portion according to an embodiment of the present application. DETAILED DESCRIPTION

[0011] In order to make the purpose, technical solution and advantages of the present application clearer, the technical solution of the present application will be clearly and completely described below in conjunction with the drawings of the embodiments of the present application. Obviously, the described embodiment is one embodiment of the present application, not all embodiments. Based on the described embodiments of the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0012] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in this application should be the usual meanings understood by people with general skills in the field to which this application belongs. If the full text involves descriptions such as "first" and "second", the "first" and "second" descriptions are only used to distinguish similar objects, and cannot be understood as indicating or implying their relative importance, sequence, or implicitly indicating the number of technical features indicated. It should be understood that the data described by "first" and "second" can be interchangeable under appropriate circumstances. If "and / or" appears in the full text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes Solution A, or Solution B, or a solution that satisfies both A and B.

[0013] The embodiment of the present application provides a liquid metal electromagnetic pump, referring to Figure 1 , including: a pipeline portion 10, the pipeline portion 10 is provided with an inlet 101 for receiving the inflow of liquid metal and an outlet 102 for conveying the liquid metal outward; a coil portion 20, the coil portion 20 is arranged on the radial outer side of the pipeline portion 10, and when the coil portion 20 is energized, it can generate a magnetic field in the pipeline portion 10 to drive the liquid metal to flow in the pipeline portion 10; a protective shell 30, which is arranged on the radial outer side of the coil portion 20 and extends along the axial direction of the pipeline portion 10 to cover the coil portion 20; a fixing portion 40, the fixing portion 40 is arranged at a position close to the inlet 101 and the outlet 102, and both ends of the protective shell 30 in the axial direction are connected to the fixing portion 40; a control portion 50, which is used to control the current in the coil portion 20, and one side of the protective shell 30 is raised to form an accommodating space 31, and the control portion 50 is arranged in the accommodating space 31.

[0014] In actual use, the inlet 101 and the outlet 102 of the pipeline portion 10 can be connected to the corresponding pipeline joints, and the coil portion 20 is arranged on the radial outside of the pipeline portion 10. When the coil portion 20 is energized, an alternating magnetic field is generated in the pipeline portion 10. The magnetic field penetrates the liquid metal in the pipeline portion 10 and generates an sympathetic current. The current interacts with the magnetic field to generate a force along the direction of the external alternating secondary traveling wave to push the liquid metal forward in the pipeline portion 10. Those skilled in the art will determine the specific location of the coil portion 20 and the winding method of the coil portion 20 based on actual conditions, and no specific limitation is made on this.

[0015] The liquid metal can be an alkali metal such as Li, Na, K, NaK alloy, Rb, Cs, or any other suitable metal. For metals that are liquid at room temperature, they can be used directly. For metals that are solid at room temperature, a heating device may need to be provided at the joint of the pipeline portion 10 (for example, at the inlet 101) to ensure that the metal entering the pipeline portion 10 is liquid metal. After the liquid metal enters the pipeline portion 10, it can be heated by the vortex effect and will not solidify.

[0016] The fixing part 40 is used to fix the protective shell 30. The fixing part 40 can be a device such as a fixing flange or other fixing devices. The protective shell 30 can be fixed to the fixing part 40 by suitable means such as screws, latches, clamping, welding, etc., and technical personnel in this field can choose according to actual needs.

[0017] One side of the protective shell 30 may be raised to form an accommodating space 31, and the control unit 50 may be disposed in the raised space 31. The protective shell 30 may be an integrated structure, or may be formed by splicing a plurality of shells, and no specific limitation is made to this. In some embodiments, a partition may be formed in the accommodating space 31 to isolate the control unit 50 and the coil unit 20 to a certain extent, and in some embodiments, a partition may not be provided. In some embodiments, the control unit 50 may be fixed to the inner wall of the protective shell 30, or may be fixed to the pipeline unit 10.

[0018] Different from the large electromagnetic pump equipment in the related art, in the liquid metal electromagnetic pump of the embodiment of the present application, the two main functional components, the coil part 20 and the control part 50, and most of the pipeline part 10 are covered by the protective shell 30, which makes the structure of the entire liquid metal electromagnetic pump more compact, especially suitable for systems with miniaturization characteristics, such as reactor auxiliary systems or various related scientific experimental devices.

[0019] In some embodiments, due to the harsh working environment in application scenarios such as reactors, in addition to the high working fluid temperature, neutron and gamma ray irradiation is a problem that the equipment must face. Usually, the working temperature of the electromagnetic pump medium can reach 525°C, and the cumulative doses of neutrons and gamma generally exceed 1019N / cm² and 109Gy. Therefore, the materials used in each component of the liquid metal electromagnetic pump must be irradiated or verified before use. Preferably, the material of the basic structure of the liquid metal electromagnetic pump can be selected without modification. The recommended long-term use temperature is 525°C and below, and it can work at 550°C for a short period of time. The structural material of the pipeline part 10 is recommended to be made of 316 or 316H austenitic stainless steel, which has good high-temperature mechanical properties and is compatible with alkali metal working fluids. The structural material of the protective shell 30 is recommended to be made of 304 or 316L austenitic stainless steel to reduce costs.

[0020] In some embodiments, the protective shell 30 may be provided with ventilation holes 32, which can be used for air flow, so as to cool the coil part 20, the control part 50, the pipeline part 10, etc. to a certain extent through natural air. In some embodiments, a temperature measuring device (not shown in the figure) may be provided to measure the temperature of the pipeline part 10, the coil part 20, the control part 50 and other parts that are prone to heat. When it is found that the temperature exceeds the standard, measures such as stopping work, reducing frequency, and auxiliary cooling can be taken in time to avoid damage to the liquid metal electromagnetic pump. Preferably, the temperature measuring device can be a thermocouple, and it is recommended to use a nickel-chromium-nickel-aluminum armored insulated thermocouple with good radiation resistance.

[0021] In some embodiments, the control unit 50 may include an electrical terminal board 51 extending axially of the pipeline portion 10, and the shape of the accommodating space 31 may be adapted to the electrical terminal board 51. Such a configuration can further reduce the overall volume of the liquid metal electromagnetic pump. The electrical terminal board 51 can control the current intensity, frequency, etc. in the coil portion 20 to achieve frequency modulation, flow modulation, voltage modulation, and power modulation of the liquid metal electromagnetic pump. It is suitable for different types of control systems and can modulate any PQ characteristic combination within the operating envelope. It is particularly suitable for use in scientific experimental devices with a wide operating range. Preferably, the electrical terminal board 51 can be made of a-type alumina ceramic or polyimide to increase its radiation resistance. In some embodiments, the control unit 50 may also include a communication device, which can be connected to the electrical terminal board 51 so as to enable remote control.

[0022] In some embodiments, reference Figure 1 The liquid metal electromagnetic pump further includes a first magnetic conductive component 60, which is disposed between the coil portion 20 and the protective shell 30, and is connected to the fixing portion 40 to fix the coil portion 20 to the pipeline portion 10, and when current is passed through the coil portion 20, the current can generate a magnetic field in the pipeline portion 10 under the action of the first magnetic conductive component 60. That is, the first magnetic conductive component 60 can simultaneously complete the generation and guidance of the magnetic field and the fixing of the coil portion 20, and such a fixing method can reduce the fixing cost of the coil portion 20, and also make the assembly and manufacturing of the liquid metal electromagnetic pump and the replacement of parts more convenient.

[0023] In some embodiments, reference Figure 1 and Figure 2, the first magnetic conductive component 60 may include a plurality of first magnetic conductive bodies 61, which are arranged along the circumference of the pipeline portion 10, each first magnetic conductive body 61 extends along the axial direction of the pipeline portion 10, and both ends of each first magnetic conductive body 61 are connected to the fixing portion 40. Preferably, the first magnetic conductive component 60 may include 6-8 first magnetic conductive bodies 61, which may be evenly arranged along the circumference of the pipeline portion 10, so as to ensure that the force of the coil portion 20 in all directions is relatively uniform, and the coil portion 20 is prevented from vibrating significantly due to electromagnetic reasons as much as possible. Compared with using an integrated first magnetic conductive component 60 (for example, a cylindrical first magnetic conductive component), using a plurality of first magnetic conductive bodies 61 can further reduce the manufacturing cost. In some embodiments, the first magnetic conductive body 61 may be formed by stacking silicon steel sheets.

[0024] In some embodiments, the protective shell 30 and the plurality of first magnetic conductors 61 can be removed from the fixing portion 40 to expose the coil portion 20. In some embodiments, the protective shell 30 and the first magnetic conductors 61 can be removed when the liquid metal electromagnetic pump has been connected to the corresponding pipeline. For example, the protective shell 30 can be formed by splicing a plurality of shells or folding a shell, and the connection of the plurality of shells or the docking of the folded shell can be detachably arranged, so that after contacting the connection between the protective shell 30 and the fixing portion 40, the protective shell 30 can be removed by contacting the connection of the above connection or the connection of the docking.

[0025] After the protective shell 30 is removed, the first magnetizer 61 can be further removed from the fixing portion 40, so that the coil portion 20 is at least partially exposed, so that the coil portion 20 can be inspected in situ without removing the liquid metal electromagnetic pump as a whole. In some embodiments, the two ends of the first magnetizer 61 can be connected to the fixing portion 40 by snapping, for example, the two ends of the first magnetizer 61 can be provided with tenons, and the fixing portion 40 can be provided with corresponding slots, so that when disassembling, the first magnetizer 61 can be disassembled by knocking, which is further convenient for inspection.

[0026] In some embodiments, reference Figure 1 , the coil portion 20 includes a plurality of coils 21 spaced apart in the axial direction of the pipe portion 10. In such an embodiment, the first magnetic conductor 61 may be formed with a plurality of protrusions 611, and when the first magnetic conductor 61 is connected to the fixing portion 40, each protrusion 611 is inserted into the gap between two adjacent coils 21 to fix the coils 21. The specific number of coils 21 may be selected by those skilled in the art, and the number, length and width of the protrusions 611 are adapted to the number of coils 21 and the specific locations of the protrusions 611, which will not be described in detail here.

[0027] In some embodiments, each coil 21 may include an annular skeleton 211, a wire 212 wound on the annular skeleton 211, and a protective layer 213 covering the outside of the wire 212. The annular skeleton 211 may be integrally formed or formed by splicing of separate parts. Preferably, an integrally formed annular skeleton 211 is used to save costs. In the actual assembly process, the annular skeleton 211 of the coil 21 may be directly sleeved on the pipeline portion 10, and then fixed using the first magnetic conductor 61. The protective layer 213 may be directly coated on the outside of the wire 212 after the wire 212 is wound on the annular skeleton 211, or may be sleeved on the outside of the wire 212 in the form of a protective ring. The protective layer 213 in the form of a protective ring can be removed from the outside of the wire 212 to expose the wire 212, so that when the coil 21 fails, the wire 212 can be replaced separately without replacing the protective layer 213.

[0028] In order to improve the high temperature resistance and radiation resistance of the coil 21, the annular skeleton 211 and the protective layer 213 can be made of α-alumina, or aluminum nitride ceramics with better heat shock resistance, but compared with α-alumina, aluminum nitride ceramics will bring higher costs. The conductor 212 can use dispersed copper plated with nickel or silver as the conductor, and use radiation-resistant mica insulated ceramic fiber as the outer layer. Both mica and ceramic fiber have good radiation resistance. Since they are generally glued, it is recommended to remove the glue and carbon after the wire 212 is wound. Preferably, the wire 212 is a flexible wire, so that when a fault occurs, the protective layer 213 can be directly removed and the wire 212 can be replaced in situ.

[0029] In some embodiments, reference Figure 4 and Figure 5 The pipeline portion 10 may include a pipe body 11, a second magnetic conductive component 12 and a support 13. The second magnetic conductive component 12 and the pipe body 11 are coaxially arranged. The support 13 supports the second magnetic conductive component 12 inside the pipe body 11, so that an annular flow channel 14 for liquid metal to flow is formed between the pipe body 11 and the second magnetic conductive component 12. The annular flow channel 14 can reduce the flow resistance of the liquid metal as much as possible, and increase the flow threshold of the fluid cavitation vibration phenomenon, greatly improving the fluid stability when the liquid metal electromagnetic pump drives the liquid metal.

[0030] In some embodiments, the second magnetic conductive component 12 may include a shell 121 and a second magnetic conductive body 122. A vacuum environment is formed in the shell 121. The second magnetic conductive body 122 is disposed in the shell 121 and extends along the axial direction of the shell 121. The vacuum environment formed in the shell 121 can ensure the cleanliness of the internal environment of the shell and avoid the possibility of interaction between unhealthy gases (such as oxygen) and the second magnetic conductive body 122. The second magnetic conductive body 122 may be made of silicon steel material. In some embodiments, the second magnetic conductive body 122 may further include a central magnetic conductive body 1221 and a plurality of silicon steel sheets 1222 radially embedded in the central magnetic conductive body 1221. Specifically, refer to Figure 4 The central magnetizer 1221 can be provided with radially arranged grooves along its diameter direction, and the silicon steel sheets 1222 are arranged in these grooves. It is recommended to use silicon steel sheets with high-temperature radiation-resistant coatings. The thickness of the silicon steel sheets can be selected between 0.2 and 0.5 mm, such as 0.35 mm. Such silicon steel sheets 1222 can block the formation of transverse induced currents, thereby improving the working efficiency of the liquid metal electromagnetic pump and the fluid stability of the liquid metal during operation.

[0031] In some embodiments, reference Figure 5 The shell 121 may include: a first shell 1211 and two second shells 1212 respectively arranged at both ends of the first shell 1211, the first shell 1211 is cylindrical, and the inner diameter of each second shell 1212 gradually decreases in the direction away from the first shell 1211. In such an embodiment, the entire shell 121 presents a torpedo shape, and the second shells 1212 with gradually decreasing inner diameters at both ends can play a good role in guiding flow and reduce the resistance of liquid metal when it flows into the annular flow channel 14. In order to ensure the vacuum environment in the shell 121, the first shell 1211 and the second shell 1212 can be sealed by electron beam welding.

[0032] In some embodiments, the support member 13 may include two main support members 131 respectively connected to the two second shells 1212. Figure 5 As shown, one end of the main support member 131 away from the second shell 1212 can be fixed to the tube body 11, and the end close to the second shell 1212 can be threadedly connected to the second shell 1212. Of course, other suitable connection methods can also be selected for connection, so as to support the second magnetic conductive component 12 in the tube body 11.

[0033] In some embodiments, reference Figure 4In addition to the two main supports 131 at both ends, a plurality of auxiliary supports 132 may be provided on the outside of the second magnetic conductive component 12 along the axial direction of the second magnetic conductive component 12, so as to further ensure the stability of the support. It should be noted that the main supports 131 and the auxiliary supports 132 need to be provided with openings for the flow of liquid metal. In addition, it is also necessary to ensure as much as possible that the main supports 131 and the auxiliary supports 132 do not affect the flow efficiency. For example, in some embodiments, the leading and trailing edges of the main supports 131 and the auxiliary supports 132 along the axial direction of the pipeline portion 10 may be designed in an arc shape, so as to be more in line with the hydraulic characteristics and reduce the resistance to the flow of liquid metal.

[0034] In some embodiments, the tube body 11 may include a first tube body 111 and two second tube bodies 112 respectively disposed at both ends of the first tube body 111, and the second tube body 112 is partially inserted into the first tube body 111 and is connected to the main support member 131. Figure 5 , one or more protrusions may be formed on the end of the main support 131 away from the second magnetic conductive component 12, and a corresponding groove may be provided on the second tube 112, so that after the second tube 112 is inserted into the first tube 111, it can form a matching connection with the main support 131. In such an embodiment, the main support 131 can also play a certain positioning role. Of course, those skilled in the art can also choose other ways to achieve the matching connection between the main support 131 and the second tube 112. The end of the second tube 112 away from the first tube 111 can be used to connect with the corresponding pipeline. Those skilled in the art can set it according to the actual application scenario, and no specific limitation is made to this. In some embodiments, an insulation layer 113 may be provided on the outside of the first tube 111. The insulation layer 113 is mainly used to prevent some liquid metal from solidifying during the pumping process, and can also reduce the heat conduction of the pipeline part 10 to the first magnetic conductive component 60 and the coil part 20.

[0035] It should be noted that although the second tube body 112 is connected to the main support member 131, it is still necessary to weld the second tube body 112 to the first tube body 111 to ensure the sealing of the entire pipeline portion 10. Preferably, electron beam welding is used, but tungsten inert gas shielding or other suitable methods can also be used for welding when conditions are not met.

[0036] In some embodiments, in order to further ensure the sealing of the pipeline portion 10, non-destructive detection can be performed on the welds of the various components of the pipeline portion 10, for example, detection can be performed using ultrasound, eddy current, X-ray, coloring, etc. In some embodiments, as a supplement or alternative, pressure tests and sealing tests can be performed.

[0037] In some embodiments, in order to further ensure the cleanliness of the interior of the pipeline portion 10, the structural materials in contact with the liquid metal need to be cleaned and vacuum degassed before assembly and welding, and the cleanliness during assembly and welding needs to be ensured.

[0038] Regarding the embodiments of the present application, it should also be noted that, in the absence of conflict, the embodiments of the present application and the features therein can be combined with each other to obtain new embodiments.

[0039] The above are only specific implementation methods of the present application, but the protection scope of the present application is not limited thereto. The protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A liquid metal electromagnetic pump, comprising: A pipeline portion, wherein the pipeline portion is provided with an inlet for receiving the inflow of liquid metal and an outlet for transporting the liquid metal outward; a coil portion, the coil portion being arranged radially outside the pipe portion, and being capable of generating a magnetic field in the pipe portion to drive the liquid metal to flow in the pipe portion when the coil portion is energized; a protective shell, arranged radially outside the coil portion and extending along the axial direction of the pipe portion to cover the coil portion; A fixing part, the fixing part is arranged at a position close to the inlet and the outlet, and two ends of the protective shell in the axial direction are connected to the fixing part; A control unit, used for controlling the current in the coil unit, one side of the protective shell is raised to form an accommodation space, and the control unit is arranged in the accommodation space; a first magnetic conductive component, the first magnetic conductive component being disposed between the coil portion and the protective shell, being connected to the fixing portion to fix the coil portion to the pipe portion, and cooperating with the coil portion to generate a magnetic field in the pipe portion when the coil portion is energized; The coil portion includes a plurality of coils spaced apart along the axial direction of the pipe portion; The first magnetic conductive assembly includes a plurality of first magnetic conductive bodies, the plurality of first magnetic conductive bodies are arranged along the circumference of the pipeline portion, each of the first magnetic conductive bodies extends along the axial direction of the pipeline portion, and both ends of each of the first magnetic conductive bodies are connected to the fixing portion; Each of the first magnetic conductors is formed with a plurality of protrusions, and when the first magnetic conductor is connected to the fixing portion, each of the protrusions is inserted into a gap between two adjacent coils to fix the coils; The two ends of the first magnetic conductor are provided with tenons, and the fixing portion is provided with corresponding slots; The pipeline section comprises: A tube body, a second magnetic conductive component and a support member, wherein the second magnetic conductive component and the tube body are coaxially arranged, and the support member supports the second magnetic conductive component inside the tube body, so that an annular flow channel for liquid metal to flow is formed between the tube body and the second magnetic conductive component; Wherein, the second magnetic conductive component comprises: A housing, wherein a vacuum environment is formed in the housing; A second magnetic conductor is disposed in the housing and extends along the axial direction of the housing; The housing comprises: A first shell and two second shells respectively arranged at both ends of the first shell, the first shell is cylindrical, the inner diameter of each second shell gradually decreases in a direction away from the first shell, and the support member includes two main support members respectively connected to the two second shells; The tube body comprises: A first tube body and two second tube bodies respectively arranged at two ends of the first tube body, wherein the second tube bodies are partially inserted into the first tube body and are cooperatively connected with the main support member; One or more protrusions are formed on one end of the main support member away from the second magnetic conductive component, and the second tube body is provided with corresponding grooves.

2. The liquid metal electromagnetic pump according to claim 1, wherein: The protective shell is provided with ventilation holes.

3. The liquid metal electromagnetic pump according to claim 1, wherein: The control part includes an electrical connection board extending along the axial direction of the pipeline part, and the shape of the accommodating space is adapted to the electrical connection board.

4. The liquid metal electromagnetic pump according to claim 1, wherein: The protective case and the plurality of first magnetic conductors are detachable from the fixing portion to expose the coil portion.

5. The liquid metal electromagnetic pump according to claim 1, wherein: Each of the coils comprises: An annular frame, a wire wound on the annular frame, and a protective layer covering the outside of the wire.

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