A liquid metal driving assembly and a driving device

Abstract

The application discloses a driving assembly and a driving device of liquid metal. The driving assembly is arranged on a rotating shaft and comprises a pair of oppositely arranged rotating discs, a surrounding component and a flat flow channel component. There is a working interval between the two rotating discs. Each rotating disc is fixedly connected with a magnet block array on a side facing the other rotating disc and generates a circumferential rotating magnetic field in the working interval when being driven. The surrounding component is arranged on each rotating disc and comprises a retaining ring and a plurality of interval arranged metal baffles. Each metal baffle and part of the components of the retaining ring partially wrap and limit the magnet blocks. The flat flow channel component is arranged in the working interval and is sleeved on the outside of the rotating shaft. The liquid metal flows in the flow channel component from an inlet to an outlet. The liquid metal is provided with driving force in the flow in the flow channel component due to the Lorentz force generated by the circumferential rotating magnetic field.

Description

Technical Field

[0001] This invention relates to the technical field of liquid metal actuation; specifically, it relates to a liquid metal actuation component and actuation device. Background Technology

[0002] In the transport and thermal management of conductive liquid metals, typical conductive liquid metal working fluids include sodium, sodium-potassium alloys, gallium-indium-tin alloys, and lead-bismuth alloys. Liquid metals possess high thermal conductivity and relatively high electrical conductivity, making them suitable for high heat flux density applications such as aerospace thermal control, electronic device heat dissipation, and metallurgical and materials processing. Meanwhile, fourth-generation fast neutron liquid metal-cooled reactors, such as sodium-cooled fast reactors and lead-cooled fast reactors, have attracted widespread attention as advanced nuclear energy technologies. Liquid metal coolants exhibit excellent thermal properties at high temperatures and contribute to improved fuel utilization. In these scenarios, transport devices must withstand long-term high temperatures, temperature gradients, and thermal cycling, while also considering engineering requirements such as material compatibility, reliable sealing, and maintainability. While liquid metals offer significant advantages as coolants, they also pose challenges to the drive systems used in liquid metal applications, particularly in achieving efficient and reliable hydrodynamic control of the flowing liquid metal within the circulation loop. Summary of the Invention

[0003] In view of this, the present invention provides a driving component and driving device for liquid metal, thereby solving or at least alleviating one or more of the above-mentioned problems and other problems existing in the prior art.

[0004] To achieve the aforementioned objective, a first aspect of the present invention provides a driving assembly for liquid metal, disposed on a rotating shaft having an axis; the driving assembly includes: a pair of opposing turntables, spaced apart on the rotating shaft; each turntable has a plurality of magnetic blocks fixedly connected to its side facing the other turntable to form an array of magnetic blocks; a working interval exists between the two turntables; in operation, the pair of opposing turntables are driven to rotate by the rotating shaft, and the array of magnetic blocks on each turntable is driven to rotate within the working interval to generate a circumferential rotating magnetic field; a protective member is disposed on each turntable, each turntable having a plurality of placement slots, and each placement slot holding a magnetic block; wherein the bottom surface of the magnetic block abuts against the corresponding placement slot, and the top surface of the magnetic block is the surface opposite to the bottom surface of the magnetic block and away from the placement slot; the protective member includes a protective ring and a plurality of spaced-apart metal baffles, each of which... The metal baffles are positioned at the corresponding placement slots; the retaining ring is connected to the circumference of the turntable; each metal baffle is connected to the retaining ring and extends along the top surface of the corresponding magnet block to form an extension, and then bends towards the direction of the turntable to form a bend, the bend abutting against the side of the corresponding magnet block, such that each metal baffle and part of the retaining ring partially encloses and limits the magnet block on the corresponding placement slot; and a flat flow channel component is disposed in the working interval and sleeved on the outside of the rotating shaft; the flat flow channel component is provided with an inlet for liquid metal entry and an outlet for liquid metal exit; in the working state, at least a portion of the flow channel component is located in the circumferential rotating magnetic field, liquid metal enters from the inlet and flows in the flow channel component and exits from the outlet, and the liquid metal is driven by the Lorentz force generated by the circumferential rotating magnetic field in the flow of the flow channel component.

[0005] In the drive assembly described above, optionally, each of the turntables is fixed to the rotating shaft by a bushing, the bushing being sleeved on the rotating shaft and fixedly connected to the rotating shaft; the bushing is provided with a boss, and the two turntables respectively abut against the two sides of the boss and are fixed to the bushing.

[0006] In the drive assembly described above, optionally, a gasket is also provided between the boss of the bushing and at least one of the turntables.

[0007] In the drive assembly described above, optionally, the portion of the flow channel component fitted onto the rotating shaft is a flat ring. In the drive assembly described above, optionally, the projection of the annular portion of the flow channel component fitted onto the rotating shaft in the axial direction lies within the coverage area of ​​the magnet array of each turntable.

[0008] In the drive assembly described above, optionally, the plurality of magnet blocks fixed on the side of each turntable facing another turntable are circumferentially equidistantly arranged near the outer edge of the turntable, and the plurality of magnet blocks are uniformly distributed throughout the entire circumference of the corresponding turntable.

[0009] In the drive assembly described above, optionally, the magnetic poles of a plurality of magnet blocks in the magnet array on one of the turntables are arranged alternately in N and S, and at the corresponding position on the other turntable in the axial direction, the magnetic poles of a plurality of magnet blocks in the magnet array are arranged alternately in S and N.

[0010] In the drive assembly described above, optionally, the magnetic poles of a plurality of magnet blocks in the magnet array on one of the turntables are arranged alternately in N and S, and at the corresponding position on another turntable in the axial direction, the magnetic poles of a plurality of magnet blocks in the magnet array are arranged alternately in S and N after being offset around the axis by an angle.

[0011] To achieve the aforementioned objective, a second aspect of the present invention provides a driving device for liquid metal, comprising the aforementioned driving assembly, the rotating shaft, and a motor, wherein the motor coaxially drives the rotating shaft, the driving assembly is disposed on the rotating shaft, and the turntable in the driving assembly is rotatable by the rotating shaft.

[0012] In the drive device described above, optionally, another set of the drive components is connected in series on the rotating shaft.

[0013] The driving component of this invention utilizes a circumferential rotating magnetic field generated by the rotation of magnet arrays on a pair of turntables. This induces a current in the liquid metal within the flow channel component. The interaction between the current and the magnetic field generates a Lorentz force, driving the liquid metal to accelerate its flow within the flow channel component. This achieves electrodeless magnetic field-driven operation of the liquid metal. Furthermore, retaining rings and metal baffles limit the movement of the magnets. Several metal baffles are spaced apart and do not form a continuous plane; in other words, the metal baffles do not form a closed conductive loop along the circumferential direction within the rotating magnetic field. This reduces circumferential eddy currents and heat generation on the side of each turntable facing the other, as well as reducing magnetic flux loss, resulting in a more concentrated effective magnetic flux entering the flow channel component. Consequently, the liquid metal can achieve a greater driving force with the same input power, and the pressure and flow rate output of the liquid metal are more stable.

[0014] The drive assembly of this invention uses bushings to coaxially position and axially clamp two turntables, stabilizing their relative positions with the flow channel component. The length of the boss on the bushing defines the axial distance between the two turntables. Optionally, shims are also provided to adjust the axial distance between the two turntables.

[0015] Optionally, in the drive assembly of the present invention, the magnet arrays on the two turntables are staggered (that is, the phase difference between the two magnet arrays), which can enhance the magnetic flux superposition and field gradient at the flow channel component.

[0016] The present invention further provides a driving device that includes the driving components described above, and therefore the driving device also has the advantages described above.

[0017] The drive device of the present invention can connect two of the above-mentioned drive components in series on the rotating shaft, which has good scalability. Attached Figure Description

[0018] The disclosure of this invention will become more apparent from the accompanying drawings. It should be understood that these drawings are for illustrative purposes only and are not intended to limit the scope of protection of this invention. In the drawings: Figure 1 This is a side view of a liquid metal driving device according to an embodiment of the present invention; Figure 2 for Figure 1 A three-dimensional structural schematic diagram of the embodiment shown; Figure 3 for Figure 1 An exploded view of a driving component in the illustrated embodiment; Figure 4 for Figure 3 A cross-sectional view of the driving component in the embodiment shown; Figure 5 for Figure 3 A partial schematic diagram of a turntable structure; Figure 6 for Figure 3 A partial schematic diagram of another turntable structure when no magnet block is placed in a mounting slot; Figure 7 for Figure 1 The illustrated embodiment is shown in cross-sectional view along the AA direction; Figure 8 for Figure 3 A schematic diagram showing the arrangement of several magnet blocks on a turntable in direction B; Figure 9 for Figure 3 A schematic diagram showing the arrangement of several magnet blocks on another turntable in direction C; Figure 10 This is a schematic diagram of the arrangement of several magnet blocks on a turntable in the C direction with a phase difference, as shown in another embodiment.

[0019] Figure label: 10-Drive device; 1-Motor; 2-Coupling; 3-Shaft; 31-Axis; F-Direction of Rotation; α-Angle; M-Center Line; E-Center Line; P-Center Line; O-Center; 4-Drive Assembly; 41-Turntable; 411-Slot; 412-Through Hole; 42-Enclosure Component; 421-Guard Ring; 422-Metal Baffle; 422a-Extension; 422b-Bending Section; 43-Magnet Block Array; 431-Magnet Block; 44-Turntable; 441-Slot; 442-Through Hole; 45-Enclosure Component; 451-Guard Ring; 452-Metal Baffle; 452a-Extension; 452b-Bending Section; 46-Magnet block array; 461-Magnet block; 47-Flow channel component; 471-Inlet; 472-Outlet; 48-Sleeve; 481-Boss; 481a-First end face; 481b-Second end face; 481c-Through hole; 49-Working interval. Detailed Implementation

[0020] Referring to the accompanying drawings and specific embodiments, the structure, composition, features, and advantages of the liquid metal driving component and driving device of the present invention will be described below by way of example; however, all descriptions should not be construed as limiting the present invention in any way.

[0021] Furthermore, for any single technical feature described or implied in the embodiments mentioned herein, or any single technical feature shown or implied in the various figures, the present invention still allows for any combination or deletion of these technical features (or their equivalents) without any technical obstacle, and thus these further embodiments according to the present invention should also be considered within the scope of this description.

[0022] In the description of this invention, it should be understood that directional terms such as "front, back, up, down, left, right," "horizontal, vertical, horizontal," and "top, bottom" indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings. These terms are used only for the convenience of describing the invention and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the scope of protection of this invention. The directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself. In the description of this application, the axial direction of the rotating shaft corresponds to... Figure 1 The X direction in the equation.

[0023] Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with the terms "first," "second," etc., may explicitly or implicitly include at least one of those features.

[0024] Traditional mechanical pumps rely on dynamic seals and bearings, which are prone to lubrication degradation and seal wear at high temperatures. Increased vibration leads to a significant increase in leakage risk and maintenance costs. To reduce the burden on dynamic seals, electromagnetic drives are widely used. The principle is to establish an electric current in a conductive fluid and interact with an external magnetic field to form a contactless driving force, avoiding direct mechanical contact with the working fluid. Existing electromagnetic drives are mainly divided into electrode type and induction type: Electrode type generates driving force by passing current through electrodes to liquid metal and cooperating with magnetic field. The structure is intuitive and the response is fast. However, electrode corrosion, polarization and contact resistance drift are prone to occur under active metal and high temperature conditions. In addition, the heat dissipation and volume of power supply and busbar bring additional burdens, and the frequency of maintenance limits availability and lifespan. Induction type relies on time-varying magnetic field to induce current in fluid without electrode contact. Among them, coil-core type has good controllability, but the winding and core losses are large, the cooling and insulation are complicated, the size and wiring are difficult to reduce, and the compact assembly is also constrained by air gap, leakage magnetic field and thermal management. Permanent magnet type generates time-varying magnetic field through magnet movement or rotation. The current loss and insulation pressure are small, the structure is more compact and easy to arrange in the near field. However, it still has engineering challenges to achieve a strong and controllable magnetic field distribution in a limited space, while suppressing leakage magnetic field, reducing parasitic eddy currents and meeting mechanical safety.

[0025] In compact, integrated liquid metal circuits, the flow channels are often curved or flattened to meet layout and heat exchange requirements. This geometry amplifies electromagnetic-fluid-thermal coupling problems: the proportion of the near-wall region increases, and if the time characteristics of the magnetic field are not properly matched with the flow channel dimensions, the induction effect will be concentrated on the surface, resulting in insufficient effective driving force. Once the supports, shields, or fasteners around the flow channel form a closed conductive loop, parasitic eddy currents are easily generated, leading to ineffective heating, magnetic flux loss, and temperature unevenness. Small gaps are beneficial for coupling, but they are extremely sensitive to manufacturing tolerances, thermal expansion, and vibration. Gap consistency directly affects pressure differential, flow stability, and electromagnetic noise. The start-up and shutdown process needs to cross the melting point and maintain an appropriate temperature window. If heating and driving are arranged separately, it will increase the number of components and wiring, increase control complexity, and increase the risk of local overheating.

[0026] At the system level, there are also common constraints: under conditions of high temperature, radiation, strong electromagnetic fields, or confined spaces, the drive unit should minimize through-wall wiring and high-loss components to facilitate maintenance and replacement; it should be able to maintain stable differential pressure and flow output under different inlet pressures and external resistances, and achieve rapid matching through a small number of adjustable parameters; unavoidable electromagnetic losses also need to be incorporated into temperature management, undertaking both preheating and insulation, and preventing material degradation through upper limit control. Although existing solutions have made progress in experiments and prototypes, in terms of comprehensive optimization of miniaturization, strong coupling, low loss, easy assembly, and long lifespan, there are still common problems such as complex structure, heavy thermal management burden, difficulty in suppressing leakage flux and eddy current bypass, and dispersed start-up, shutdown, and safety strategies.

[0027] Therefore, it is necessary to propose an electromagnetic drive scheme that does not require electrodes and coils to be energized, is suitable for small gaps and compact arrangements, and is compatible with non-linear or flat flow channels, so as to provide target differential pressure and flow rate by adjusting the motor speed while ensuring temperature management and maintenance.

[0028] In view of this, this application provides a driving component for liquid metal, which provides driving force for liquid metal. The driving component will be described below through specific embodiments.

[0029] Figures 1 to 10 The structure of the liquid metal driving device and its components according to various embodiments of the present invention is shown.

[0030] like Figures 1 to 10 As shown, the liquid metal driving assembly 4 provided in this embodiment of the invention is mounted on a rotating shaft 3, which is driven by a motor 1 and rotates in the direction indicated by F. The rotating shaft 3 has an axis 31; the driving assembly 4 includes: a pair of oppositely arranged turntables (turntables 41 and 44 in the figure), enclosure components (corresponding enclosure components 42 and 45 in the figure), and a flat flow channel component 47.

[0031] A pair of opposing turntables 41 and 44 are spaced apart on a rotating shaft 3. Multiple magnetic blocks 431 are fixedly connected to the side of turntable 41 facing the other turntable 44, forming an array of magnetic blocks 43. Multiple magnetic blocks 461 are fixedly connected to the side of turntable 44 facing turntable 41, forming an array of magnetic blocks 46. A working interval 49 exists between turntables 41 and 44. In operation, turntables 41 and 44 are driven to rotate by the rotating shaft 3, causing the two sets of magnetic blocks on them to rotate and generate superimposed circumferential rotating magnetic fields within the working interval 49. Here, circumferential refers to the direction surrounding axis 31. Turntables 41 and 44 are respectively provided with enclosure components 42 and 45; as shown in the figure, on one side, turntable 41 is provided with several placement slots 411, and a magnetic block 431 is placed in each placement slot 411. The bottom surface of the magnetic block 431 contacts the placement slot 411, and the top surface of the magnetic block 431 is the surface of the side opposite to the bottom surface and away from the placement slot 411; the enclosure component 42 includes a protective ring 421 and several spaced metal baffles 422, each metal baffle 422 being positioned in a corresponding placement slot 411; the protective ring 421 is welded to the circumference of turntable 41. Figure 5 As shown in the diagram, for ease of illustration, the metal baffle 422 is an L-shaped component, including an extension 422a extending along the top surface of the corresponding magnet block 431 and a bent portion 422b bending towards the corresponding mounting slot 411. One end of the extension 422a is connected to the retaining ring 421, and the other end is connected to the bent portion 422b. The bent portion 422b abuts against the side of the magnet block 431. In this way, the metal baffle 422 and part of the retaining ring 421 partially enclose and limit the magnet block 431 on the corresponding mounting slot 411. Similarly, the other turntable 44, which is arranged opposite to it in the figure, is also provided with a protective component 45. The protective component 45 has the same structure as the protective component 42. The turntable 44 is provided with several placement slots 441, and a magnetic block 461 is placed in each placement slot 441. The bottom surface of the magnetic block 461 contacts the placement slot 441, and the top surface of the magnetic block 461 is the side surface opposite to the bottom surface and away from the placement slot 441. The enclosure component 45 includes a protective ring 451 and several spaced-apart metal baffles 452, each metal baffle 452 being positioned in a corresponding placement slot 441. The protective ring 451 is welded to the circumference of the turntable 44. Figure 3 and Figure 6 ,in Figure 6The image shows the state of each magnet block 461 placed in its corresponding slot 441. For simplicity, one slot 441 is shown without a magnet block. The metal baffle 452 is an L-shaped component, including an extension 452a extending along the top surface of the corresponding magnet block 461 and a bent portion 452b bending towards the corresponding slot 441. One end of the extension 452a is connected to the retaining ring 451, and the other end is connected to the bent portion 452b. The bent portion 452b abuts against the side of the magnet block 461. In this way, the metal baffle 452 and part of the retaining ring 451 partially enclose and limit the magnet block 461 in the corresponding slot 441. The depth of each slot is 2mm.

[0032] In this embodiment, the metal baffle is an L-shaped component, including an extension and a bent portion. The extension extends on the top surface of the corresponding magnet block, with one end welded to the retaining ring and the other end connected to the bent portion. The bent portion abuts against the side of the corresponding magnet block, which is the surface opposite to and away from the retaining ring. In other words, the retaining ring, the metal baffle, and the turntable's mounting groove together surround and limit the corresponding magnet block. The metal baffle can be an iron sheet.

[0033] A flat flow channel component 47 is disposed in the working interval 49 and sleeved on the outside of the rotating shaft 3, and is fixed as a whole on the frame (not shown in the figure). The cross-section of the flow channel component 47 is a flat rectangle, and the central plane of the flow channel component 47 is basically parallel to the end faces of the turntables on both sides of the flow channel component. The flat flow channel component 47 is provided with an inlet 471 for liquid metal to enter and an outlet 472 for liquid metal to flow out. In the working state, at least a part of the flow channel component 47 is located in the circumferential rotating magnetic field. Liquid metal enters from the inlet 471, flows in the flow channel component 47 and flows out from the outlet 472. Due to the Lorentz force generated by the circumferential rotating magnetic field, the liquid metal is provided with driving force in the flow of the flow channel component 47.

[0034] In an embodiment not shown, bent portions may also be connected to both sides of the extension of the L-shaped metal baffle, which abut against the other two sides of the magnet block, thus further securing the magnet block. In another embodiment not shown, a bent portion is provided on one side of the extension of the metal baffle, which abuts against the corresponding side of the magnet block to secure the magnet block.

[0035] Each pair of turntables has its own magnetic array, with the working interval 49 between the two turntables controlled at the millimeter level. This allows the two sets of magnetic arrays to easily establish stable electromagnetic coupling. As the two turntables rotate with the axis, their respective electromagnetic arrays generate circumferential rotating magnetic fields at the location of the flow channel component 47, which then superimpose on each other. The liquid metal within the flow channel component 47, located within this superimposed circumferential rotating magnetic field, generates an induced current. This induced current interacts with the circumferential rotating magnetic field to produce a Lorentz force, which drives the liquid metal to flow more rapidly within the flow channel component 47. This enables electrodeless actuation of the liquid metal without the need for external AC power or coils. In other words, the drive component requires no electrodes or energized coils, avoiding electrochemical corrosion, insulation aging, and the heat dissipation burden of the windings, thus reducing maintenance difficulty in high-temperature environments. The circumferential rotating magnetic fields generated by the respective electromagnetic arrays at the location of the flow channel component 47, combined with each other, effectively expand the coverage of the flow channel component 47 area.

[0036] The circumferential rotating magnetic field also exhibits electromagnetic losses during operation, which can be used as an induction heating heat source for preheating and maintaining the temperature of the flow channel component 47 and its interior. However, it needs to be combined with heat dissipation or temperature control design to avoid localized overheating. In this way, the preheating and temperature maintenance of the liquid metal, as well as the driving process of the liquid metal, are integrated, facilitating rapid start-up and shutdown and coordinated temperature control.

[0037] Each magnet block is supported by a corresponding mounting slot on the turntable. A retaining ring is concentrically positioned on the outer circumference of the turntable, serving as a mechanical constraint boundary to prevent high-speed ejection and providing outer edge protection. Metal baffles are welded integrally with the retaining rings, enclosing and fixing the magnet blocks on one side of the working interval. Thus, the magnet blocks are enclosed and fixed through the mounting slots, retaining rings, and metal baffles. The metal baffles fixing each magnet block are spaced apart, not forming a continuous plane; in other words, the metal baffles do not form a closed conductive loop along the circumferential direction in the circumferential rotating magnetic field. This reduces circumferential parasitic eddy currents and their heating on the side of each turntable facing the other, and suppresses magnetic flux leakage, making the effective magnetic flux entering the flow channel component more concentrated. Consequently, the liquid metal can obtain a greater driving force at the same input power, and the pressure and flow output of the liquid metal are more stable.

[0038] In this embodiment, a flat channel component is arranged opposite to a coaxial dual-disc interval (millimeter-level interval); the center plane of the channel component is basically parallel to the end face of the disc. The working interval is measurable and has an accurate numerical specification during assembly, and the working interval remains consistent over a long period of operation to obtain stable electromagnetic coupling, thereby obtaining repeatable differential pressure and flow rate output of liquid metal.

[0039] In a preferred embodiment, both turntables 41 and 42 are fixed to the rotating shaft 3 by bushings 48. The bushings 48 are fitted onto the rotating shaft 3 and are fixedly connected to the rotating shaft 3 by fasteners (e.g., key pins and screws). The bushings 48 are provided with bosses 481, which have a first end face 481a and a second end face 481b on both sides, and have a plurality of through holes 481c penetrating the first end face 481a and the second end face 481b. Turntable 41 abuts against the first end face 481a, and turntable 44 abuts against the second end face 481b. Turntables 41 and 44 are respectively provided with a plurality of through holes 412 and a plurality of through holes 442, and the through holes 412, 481c and 442 correspond one-to-one. Turntables 41 and 44 are fixed to both sides of boss 481 using fasteners (not shown in the figure) with bolts and nuts, through holes 412, 481c, and 442 respectively. A bushing 48 is used to coaxially position and clamp the two turntables, stabilizing their relative positions to the flow channel component 47. The axial length of the boss 481 on the bushing 48 defines the axial (X-direction) distance between the two turntables, and also defines the working interval 49, which has an axial dimension in the millimeter range. The flow channel component 47 is fixed to the frame (not shown in the figure) and is a fixed component. The bushing 48 cooperates with the frame positioning component to define the relative positions of the two turntables to the flow channel component 47. The two turntables pass through the bushings at their center positions. Each set of magnet blocks is arranged away from the center and close to the outer edge of its respective turntable. Thus, the bushings are located in the non-operational region of the circumferential rotating magnetic field formed by the two sets of magnet blocks.

[0040] Furthermore, a shim (not shown in the figure) can be provided between the first end face 481a of the bushing boss and the turntable 41, and a shim (not shown in the figure) can also be provided between the second end face 481b and the turntable 44, so that the axial (X direction) distance between the two turntables can be appropriately adjusted.

[0041] In this embodiment, both the turntable and the bushing are made of stainless steel; in other embodiments, other metal materials may be used, and there is no limitation here. The magnet block is a permanent magnet block.

[0042] As shown in the figure, the magnet array 43 of the turntable 41 is arranged in an annular zone near the outer edge of the turntable 41 (in other words, the annular area formed on the turntable 41 by the magnet array 43 when rotating around the axis 31), and the magnet array 46 of the turntable 44 is arranged in an annular zone near the outer edge of the turntable 44 (in other words, the annular area formed on the turntable 44 by the magnet array 46 when rotating around the axis 31). The portion of the flow channel component 47 that fits onto the rotating shaft 3 is a flat annular shape. Viewed in the axial direction (X), the flow channel component 47 has an inverted "Ω" shape. The annular portion of the flow channel component 47 corresponds to the magnet array within the annular zone in the axial direction. The width of the annular portion of the flow channel component 47 is slightly less than or equal to the width of the annular band (the width of the annular band refers to the width of the annular band in the radial direction of the corresponding turntable; the width of the annular portion of the flow channel component 47 refers to the length of the long side of the outer rectangular section of the flow channel component 47). Thus, the projection of the annular portion of the flow channel component 47 onto the rotating shaft in the axial direction lies within the coverage area of ​​the magnet array on each turntable (i.e., the corresponding annular band). If the annular band corresponding to the magnet array is too narrow, the force generated by the magnetic field cannot cover the width of the flow channel component; if the annular band corresponding to the magnet array is too wide, the portion of the annular band extending axially beyond the flow channel component causes increased leakage flux and losses. As the two turntables rotate with the axis, the two sets of magnet arrays generate superimposed circumferential rotating magnetic fields at the position of the flow channel component 47. In the tangential direction of the flow channel near the “Ω”-shaped flow channel component 47, it is locally equivalent to a traveling magnetic field along the flow channel direction. This is advantageous when driving liquid metal to flow in the flow channel of the flow channel component 47. The circumferential rotating magnetic field induces a current in the liquid metal. The induced current interacts with the circumferential rotating magnetic field to generate a Lorentz force along the flow channel direction. The Lorentz force thus drives the flow of liquid metal.

[0043] like Figure 8 , Figure 9 and Figure 10 As shown, multiple magnetic blocks fixed on the side of each turntable facing another turntable are equidistantly arranged circumferentially within a ring near the outer edge of the turntable. These magnetic blocks are uniformly distributed throughout the entire circumference of the corresponding turntable; that is, the multiple magnetic blocks on each turntable form a magnetic ring array. In embodiments not shown in other figures, at least one turntable has magnetic blocks uniformly arranged only on a portion of its circumference.

[0044] In one embodiment, the aforementioned magnet blocks are of the same type and appear in pairs, all of which are permanent magnets. Figure 8 for Figure 3 The diagram shows the direction of B in the diagram. Figure 8 In the middle, the magnetic poles of 10 pairs of magnetic blocks 431 in the magnet block array 43 on a turntable 41 are arranged alternately with N and S. Figure 9 for Figure 3 The diagram shows the C direction. Figure 9In the center, at the corresponding position on another turntable 44 along axis 31, the magnetic poles of the 10 pairs of magnetic blocks 461 in the magnet array 46 are arranged alternately in a S and N pattern. That is, the magnetic poles of the two turntables' magnet arrays are aligned one-to-one (at this time, the two sets of magnet arrays do not have a circumferential phase difference). An example is provided using a magnet block at one location. Figure 8 The central magnet block array 43 has 10 pairs of magnet blocks and a center line M in the Z direction. The center line M is exactly the center line of the magnet block in the 12 o'clock direction, and the magnetic poles of the magnet block in the 12 o'clock direction are S and N from top to bottom. Figure 9 The magnet block array 46 also has 10 pairs of magnet blocks and a center line E in the Z direction. The center line E is exactly the center line of the magnet block in the 12 o'clock direction, and the magnet blocks in the 12 o'clock direction are N and S from top to bottom.

[0045] In another embodiment, compared to the previous embodiment Figure 9 , Figure 10 This represents the case where the two sets of magnet arrays have a phase difference, rotated clockwise by an angle α around center O. The magnets mentioned above are of the same type and appear in pairs; all are permanent magnets. For example... Figure 8 As shown, the magnetic poles of 10 pairs of magnet blocks in the magnet array 43 on a turntable 41 are arranged alternately with N and S poles. Figure 10 As shown, at the corresponding position of another turntable 44 along axis 31, the magnetic poles of 10 pairs of magnet blocks in the magnet array are offset around the axis by an angle α (that is, there is a circumferential phase difference between the two sets of magnet arrays) and then arranged alternately in S and N. An example is given using a magnet block at one position. Figure 8 The central magnet block array 43 has 10 pairs of magnet blocks and a center line M in the Z direction. The center line M is exactly the center line of the magnet block in the 12 o'clock direction, and the magnetic poles of the magnet block in the 12 o'clock direction are S and N from top to bottom. Figure 10 The magnet array 46 also has 10 pairs of magnets and a Z-axis centerline P. Magnets near centerline P have a centerline E, which passes through the center O of the magnet array 46. The magnets near centerline P are numbered N and S from top to bottom, and the centerlines P and E form an angle α. That is, the magnet arrays on the two turntables have a circumferential phase difference. If each turntable has n magnets, the offset angle α needs to be less than 360° / n. A predetermined circumferential phase is set between the two turntables to achieve magnetic flux superposition and field gradient enhancement on the channel side, and to expand the effective coverage of the liquid metal region. The two turntables form superimposed circumferential rotating magnetic fields in the flow channel assembly, and the two sets act sequentially with a gradient in the flow direction to increase the pressure difference output of the liquid metal.

[0046] When the magnetic poles of the two turntables' magnet arrays are aligned one by one, that is, when there is no circumferential phase difference, the angle α is 0°, and the combined amplitude of the magnetic induction intensity in the channel of the flow channel component 47 is the largest, which is the theoretical optimal value for improving the pressure difference output (that is, the driving force of the liquid metal).

[0047] The magnet arrays of the two turntables are set with a predetermined phase difference in the circumferential direction. At this time, α is greater than 0°. The liquid metal in the flow channel component 47 is pushed by the magnetic field generated by the two sets of magnet arrays in the circumferential direction. The peak thrust concentrated at a single position is spread in the circumferential direction, thereby providing a more stable Lorentz thrust over a longer circumferential range. This is beneficial to reduce the pressure difference and flow pulsation of the liquid metal, and reduce the stress and vibration of the structure caused by local electromagnetic force.

[0048] In this embodiment, as Figure 1 and Figure 2 As shown, the liquid metal drive device 10 includes a motor 1, a coupling 2, a rotating shaft 3, and two sets of drive assemblies 4 connected in series on the rotating shaft 3. The coupling 2 is installed between the motor 1 and the rotating shaft 3 and is coaxially connected for centering, used to transmit torque and compensate for minor eccentricity and axial movement, driving the two sets of drive assemblies 4 to rotate synchronously. The motor 1 inputs controllable torque to the coaxial rotating shaft 3 via the coupling 2, used to drive the two sets of drive assemblies 4 to rotate synchronously, and to set the frequency and circumferential speed of the equivalent magnetic field. The rotating shaft 3, supported on two bearing seats and passing through the center of each turntable, is used to transmit the torque and angular velocity output by the motor 1 to the drive assemblies 4.

[0049] When motor 1 is working, it synchronously drives two sets of coaxially arranged drive components 4 to rotate via coupling 2. In drive components 4, the spacing between each pair of turntables is small, and each pair has a ring of circumferentially equidistant magnets with alternating N and S poles embedded on its outer edge. Each pair of turntables forms a superimposed circumferential rotating magnetic field on the flow channel component side, which is equivalent to a traveling magnetic field along the flow channel direction in the tangential direction of the flow channel near the flow channel component. This rotating magnetic field induces a current in the liquid metal. Due to the effects of conductivity and magnetic diffusion, there is an electromagnetic phase difference between the induced current and the rotating magnetic field (referring to the phase difference between the current and the magnetic field, which is independent of the mechanical phase of the two turntables). The interaction between the two generates an average Lorentz force along the flow channel direction, thereby driving the liquid metal to circulate within the flow channel.

[0050] In other embodiments, one or more sets of the aforementioned drive components 4 may be provided on the rotating shaft, which is not limited here. The motor 1 directly drives the coaxial rotating shaft 3 via the coupling 2, eliminating the need for an outer cylinder and gear steering mechanism. This significantly reduces the number of system-level components and transmission chain levels, resulting in a more compact overall design.

[0051] When liquid metals require higher pressure differentials or larger flow rates, multiple coaxial drive components can be connected in series along the flow direction to form a multi-stage drive (i.e., multi-stage expansion). This improves the overall drive capability while maintaining the system's compactness, ease of assembly, and maintenance accessibility. Balancing pressure differential capability and overall size under varying installation space and system resistance conditions demonstrates excellent scalability, ease of assembly, and long-term reliability.

[0052] The driving device 10 of this embodiment includes the aforementioned driving component 4, thereby having all the advantages of the driving component 4.

[0053] The liquid metal in the above embodiments can be liquid sodium, liquid lead, or liquid lead-bismuth at high temperatures, or a gallium-based alloy (such as Ga–In–Sn–Zn alloy) liquid at room temperature. The high-temperature state can be 200 ℃–300 ℃, and the room temperature state can be 20 ℃–30 ℃. The above-mentioned drive device can meet the needs of various energy and power engineering systems, and has greater flexibility and reliability.

[0054] Liquid metal flows as the working fluid within the flow channel of the flow channel component 47. Below a certain temperature, the liquid metal is solid and cannot flow within the flow channel. Therefore, the temperature at the location of the flow channel component 47 is a crucial indicator when driving the liquid metal flow. When the flow channel component 47 is not filled or its temperature is below the set temperature required for filling, motor 1 is started, and drive assembly 4 rotates accordingly. The time-varying magnetic field generated by the magnet array induces eddy currents in the wall and near-wall conductors of the flow channel component 47, generating Joule heating to achieve induction heating, bringing it to a temperature range suitable for filling and stable flow of the liquid metal. When the working fluid within the flow channel component 47 is solid, motor 1 is started, and drive assembly 4 rotates accordingly. The time-varying magnetic field generated by the magnet array continuously induces eddy currents in the flow channel component 47, heating it until the solid working fluid melts and is maintained at the set temperature (e.g., the temperature at which the liquid metal can flow stably). When the working fluid inside the flow channel component 47 is liquid, motor 1 is started, synchronously driving the two sets of drive components to rotate, thereby forming a superimposed circumferential rotating magnetic field at the location of the flow channel component (which can be equivalent to a magnetic field traveling along the flow channel direction in the tangential region near the flow channel component). The liquid metal in the cavity of the flow channel component generates an induced current, which interacts with the circumferential rotating magnetic field to generate a Lorentz force along the flow channel direction, thereby driving the liquid metal to flow in the Ω-shaped flow channel. When the driving of the liquid metal ends (that is, when the machine stops), the motor speed is gradually reduced according to the preset ramp deceleration, so that the stainless steel turntable with embedded permanent magnets decelerates smoothly, ensuring a smooth transition of the liquid metal flow; when the flow rate and pressure difference drop to the safe threshold, the drive power is turned off, and the safe shutdown is completed.

[0055] To meet different requirements for driving liquid metal (e.g., target driving force, target pressure difference, and flow rate), adjustments can be made to the motor speed, the number of pole pairs in the magnet array, the coverage arc length of the magnet array within the ring, and the working interval. The number of pole pairs refers to the number of pairs of N / S magnetic poles appearing in one ring of the magnet array. For example, if each turntable has 20 magnets arranged alternately with N and S poles, there are 10 pairs; a higher number of pole pairs is beneficial for increasing the pressure difference of the working fluid. A smaller working interval provides a greater driving force to the liquid metal, which is more conducive to improving the pressure difference and flow rate; however, an excessively small working interval increases the risk of friction and collision between components. An excessively large working interval weakens the driving force provided to the liquid metal, causing a simultaneous decrease in pressure difference and efficiency. The coverage arc length of the magnet array within the annular zone (the approximate angular range of a single magnet block along the circumference (whether it covers the entire circumference or only a certain segment)) can be engineered and adjusted according to the target operating conditions to achieve pressure differential and flow rate matching under the same shape. The aforementioned drive device has high pump power, can start and stop quickly, and has good scalability.

[0056] The technical scope of this invention is not limited to the contents of the above specification. Those skilled in the art can make various modifications and variations to the above embodiments without departing from the technical concept of this invention, and all such modifications and variations should fall within the scope of this invention.

Claims

1. A driving assembly for liquid metal, disposed on a rotating shaft having an axis; characterized in that, The driving component includes: A pair of opposing turntables are spaced apart on the rotating shaft; each turntable has multiple magnet blocks fixedly connected to its side facing the other turntable to form an array of magnet blocks; there is a working interval between the two turntables; in the working state, the pair of opposing turntables are driven to rotate by the rotating shaft, and the array of magnet blocks on each turntable is driven to rotate in the working interval to generate a circumferential rotating magnetic field; An enclosure component is disposed on each of the turntables, each turntable having a plurality of placement slots, and each placement slot holding a magnetic block; wherein the bottom surface of the magnetic block abuts against the corresponding placement slot, and the top surface of the magnetic block is the surface opposite to the bottom surface of the magnetic block and away from the placement slot; the enclosure component includes a protective ring and a plurality of spaced-apart metal baffles, each metal baffle being disposed at a position corresponding to a placement slot; the protective ring is connected to the circumference of the turntable; each metal baffle is connected to the protective ring and extends along the top surface of the corresponding magnetic block to form an extension, and then bends towards the direction corresponding to the turntable to form a bend, the bend abutting against the side of the corresponding magnetic block, such that each metal baffle and part of the protective ring partially encloses and limits the magnetic block on the corresponding placement slot; and... A flat flow channel component is disposed in the working interval and sleeved on the outside of the rotating shaft; the flat flow channel component is provided with an inlet for liquid metal to enter and an outlet for liquid metal to flow out; in the working state, at least a portion of the flow channel component is located in the circumferential rotating magnetic field, the liquid metal enters from the inlet and flows in the flow channel component and flows out from the outlet, and the flow of liquid metal in the flow channel component is driven by the Lorentz force generated by the circumferential rotating magnetic field.

2. The driving component according to claim 1, characterized in that, Each of the turntables is fixed to the rotating shaft by a bushing, the bushing being fitted onto the rotating shaft and fixedly connected to it; the bushing is provided with a boss, and the two turntables respectively abut against the two sides of the boss and are fixed to the bushing.

3. The driving component according to claim 2, characterized in that, A gasket is also provided between the boss of the bushing and at least one of the turntables.

4. The driving component according to claim 1, characterized in that, The portion of the flow channel component that fits onto the rotating shaft is a flat ring.

5. The driving component according to claim 4, characterized in that, The projection of the annular portion of the flow channel component fitted onto the rotating shaft in the axial direction lies within the coverage area of ​​the magnet array of each turntable.

6. The driving device according to claim 1, characterized in that, The plurality of magnet blocks fixed on the side of each turntable facing the other turntable are circumferentially equidistantly arranged near the outer edge of the turntable, and the plurality of magnet blocks are uniformly distributed throughout the entire circumference of the corresponding turntable.

7. The driving component according to claim 1, characterized in that, The magnetic poles of several magnetic blocks in the magnet array on one of the turntables are arranged alternately in N and S. At the corresponding position on another turntable in the axial direction, the magnetic poles of several magnetic blocks in the magnet array are arranged alternately in S and N.

8. The driving component according to claim 1, characterized in that, The magnetic poles of several magnetic blocks in the magnet array on one of the turntables are arranged alternately in N and S. At the corresponding position on another turntable in the axial direction, the magnetic poles of several magnetic blocks in the magnet array are arranged alternately in S and N after being offset around the axis by an angle.

9. A driving device for liquid metal, characterized in that, The device includes the drive assembly, the rotating shaft, and the motor as described in any one of claims 1 to 8, wherein the motor coaxially drives the rotating shaft, the drive assembly is disposed on the rotating shaft, and the turntable in the drive assembly can be driven to rotate by the rotating shaft.

10. The driving device according to claim 9, characterized in that, Another set of drive components is connected in series on the rotating shaft.

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