CN112803713B - Liquid metal electromagnetic pump - Google Patents

Abstract

The embodiment of the invention discloses a liquid metal electromagnetic pump, which comprises: a liquid flow pipe (30) extending vertically and defining a passage therein having a uniform inner diameter and having openings at upper and lower ends; and an electromagnetic drive device for providing an electromagnetic force for driving the liquid metal to flow into the passage from the lower end opening of the flow conduit (30) and outwardly via the upper end opening of the flow conduit (30), the electromagnetic drive device comprising: the outer iron core extends along the vertical direction at the radial outer side of the liquid flow pipeline (30), and is provided with a plurality of winding grooves along the vertical direction; and a plurality of coils (10) sleeved on the radial outer side of the liquid flow pipeline (30), wherein each coil (10) is arranged in one winding groove of the outer iron core. The technical scheme of the invention can improve the working stability of the liquid metal electromagnetic pump in the prior art.

Description

Liquid metal electromagnetic pump

Technical Field

The invention relates to the technical field of electromagnetic pumps, in particular to a liquid metal electromagnetic pump.

Background

As an important liquid metal conveying device, the liquid metal electromagnetic pump has the advantages of no medium contact, no moving part, complete sealing, simple and convenient maintenance and the like, and is widely applied to the field of nuclear power. The temperature of the medium of the electromagnetic pump in the nuclear safety level application scene of the reactor engineering is generally higher, and the reliability requirement is severer. At present, the working stability of a liquid metal electromagnetic pump is not high, and the nuclear safety level application requirement of reactor engineering cannot be met.

Disclosure of Invention

The invention aims to improve the working stability of the liquid metal electromagnetic pump.

In order to achieve the above object, the present invention provides a liquid metal electromagnetic pump, comprising: the liquid flow pipeline extends vertically, and a channel with uniform inner diameter and openings at the upper end and the lower end is limited in the liquid flow pipeline; and an electromagnetic driving device for providing an electromagnetic force for driving the liquid metal to flow into the channel from the opening at one end of the liquid flow pipe and flow out through the opening at the other end of the liquid flow pipe, the electromagnetic driving device comprising: the external iron core extends along the vertical direction at the radial outer side of the liquid flow pipeline, and is provided with a plurality of winding grooves along the vertical direction; and a plurality of coils, which are sleeved on the radial outer side of the liquid flow pipeline, wherein each coil is arranged in one winding slot of the external iron core.

Drawings

Other objects and advantages of the present invention will become apparent from the following description of the invention which refers to the accompanying drawings, and may assist in a comprehensive understanding of the invention.

FIG. 1 is a schematic diagram of a liquid metal electromagnetic pump according to one embodiment of the present invention;

FIG. 2 is an enlarged view of a portion of the area A shown in FIG. 1;

fig. 3 is a schematic structural view of the bar-shaped iron core shown in fig. 1;

FIG. 4 is a partial enlarged view of the area B shown in FIG. 3;

FIG. 5 is a schematic cross-sectional view of the liquid metal electromagnetic pump shown in FIG. 1;

FIG. 6 is an enlarged view of a portion of the area C shown in FIG. 5;

FIG. 7 is an enlarged view of a portion of the area D shown in FIG. 5;

FIG. 8 is a schematic block diagram of the housing shown in FIG. 5;

FIG. 9 is a schematic cross-sectional view of the housing shown in FIG. 8;

FIG. 10 is a cross-sectional view of the liquid metal electromagnetic pump of FIG. 1 taken in another direction;

FIG. 11 is an enlarged fragmentary view of the liquid metal electromagnetic pump of FIG. 10;

FIG. 12 is a schematic cross-sectional view of the fluid flow conduit of FIG. 1;

FIG. 13 is a top plan view of the liquid metal electromagnetic pump shown in FIG. 1;

FIG. 14 is a partial schematic structural view of the lower mounting assembly shown in FIG. 1;

FIG. 15 is a schematic structural view of the second mounting portion of FIG. 1;

fig. 16 is a partially enlarged view of the region E shown in fig. 15.

It is noted that the drawings are not necessarily to scale and are merely illustrative in nature and not intended to obscure the reader.

Description of reference numerals:

100. a liquid metal electromagnetic pump; 10. a coil; 20. a strip-shaped iron core; 21. slotting the iron core; 22. a heat dissipation structure; 23. a mounting member; 30. a liquid flow conduit; 31. an inlet section; 311. a limiting part; 32. an outlet section; 321. a chucking section; 33. a middle connecting section; 40. a support leg; 41. a first mounting portion; 411. a first heat dissipation hole; 412. a second heat dissipation hole; 413. a first central aperture; 42. a second mounting portion; 421. the mounting part is provided with a groove; 422. a boss portion; 423. a rib; 43. a heat insulating spacer; 44. a first fastener; 45. a fastener; 50. an inner core; 51. a containing groove; 60. a housing; 61. a first flow guide section; 62. a second flow guide section; 63. a casing section; 64. an inner support tube; 65. welding the part; 66. a support portion; 67. an elastic portion; 70. an insulating layer.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions of the present invention will be described in detail and completely with reference to the accompanying drawings of the embodiments of the present application. It should be apparent that the described embodiment is one embodiment of the invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the described embodiments of the invention without any inventive step, are within the scope of protection of the invention.

It is to be noted that technical terms or scientific terms used herein should have the ordinary meaning as understood by one of ordinary skill in the art to which the present invention belongs, unless otherwise defined. References throughout to "first", "second", etc., are used merely to distinguish between similar items and are not to be construed as indicating or implying a relative importance, order, or number of technical features indicated, and it is to be understood that the data described in "first", "second", etc. may be interchanged where appropriate. Furthermore, spatially relative terms, such as "upper," "lower," "top," "bottom," and the like, may be used herein for ease of description to describe one element or feature's spatial relationship to another element or feature as illustrated in the figures, and should be understood to encompass different orientations of the element or feature in use or operation in addition to the orientation depicted in the figures.

At present, a liquid metal electromagnetic pump applied to the nuclear power field generally adopts a horizontal layout (namely, when liquid metal is pumped, a liquid flow pipeline of the liquid metal electromagnetic pump is arranged along the horizontal direction). During the working process of pumping high-temperature liquid metal, the liquid metal electromagnetic pump often fails due to poor stability of the liquid metal electromagnetic pump caused by high-temperature magnetic loss of an external iron core. In the related art, a cooling fan is used to perform forced air cooling heat dissipation on a liquid metal electromagnetic pump. However, the internal environment of the reactor is severe, and the reliability of the liquid metal electromagnetic pump is greatly reduced by using the cooling fan.

The inventor of this application is carrying out the in-process that improves to liquid metal electromagnetic pump to above-mentioned technical problem and discovers, and the liquid metal electromagnetic pump of horizontal overall arrangement is comparatively short usually, and vertical heat dissipation is highly limited, hardly solves the heat dissipation problem through the mode of pure natural convection. Moreover, in the prior art, the liquid metal electromagnetic pump installed horizontally has a liquid flow pipe with an outer diameter generally larger than that of the pipe connected with the liquid metal electromagnetic pump. For the matching interface, need add at the both ends of liquid flow pipeline and establish the convergent reducing pipe for liquid flow pipeline among the prior art has thick both ends thin structure in the middle, and this kind of structure makes liquid flow pipeline produce local high point and local low point simultaneously, therefore the liquid medium of liquid flow pipeline bottom is difficult to the evacuation (hydrops), and runner top gas also piles up easily (gas accumulation), has hydrops and gas accumulation risk. In addition, for the liquid metal electromagnetic pump that the liquid flow pipeline was placed horizontally, even the internal diameter at liquid flow pipeline both ends was unanimous with the interlude internal diameter, namely the internal diameter of liquid flow pipeline is homogeneous, so the liquid medium of liquid flow pipeline bottom also hardly empties completely, and runner top gas still has a small amount of accumulations, has hydrops and long-pending gas risk. In view of the fact that liquid metal driven by a liquid metal electromagnetic pump is usually inflammable and explosive (such as sodium, potassium and cesium) or extremely toxic (such as lead and mercury), the problem of liquid accumulation enables maintenance and replacement of the liquid metal electromagnetic pump to become high-risk operation, and the problem of gas accumulation seriously hinders the operation safety of the liquid metal electromagnetic pump.

Therefore, in order to at least partially solve the above-mentioned problems of the liquid metal electromagnetic pump, the inventors of the present application have made the following improvements to the structure of the liquid metal electromagnetic pump.

Referring to fig. 1 to 5, a liquid metal electromagnetic pump 100 according to an embodiment of the present application may include: a fluid flow conduit 30 and an electromagnetic drive. The liquid flow pipe 30 extends in a vertical direction (i.e., a vertical direction), and defines therein a passage having openings at upper and lower ends. In some embodiments, the lower end opening of the flow conduit 30 serves as a flow inlet for receiving the inflow of liquid metal, and the upper end opening serves as a flow outlet for delivering the liquid metal outwardly. In other embodiments, the upper end of the flow conduit 30 is open to receive liquid metal and the lower end is open to deliver liquid metal to the outside.

The electromagnetic driving device is used for providing electromagnetic force for driving the liquid metal to flow from the liquid flow inlet (one end opening of the liquid flow pipeline 30) to the liquid flow outlet (the other end opening of the liquid flow pipeline 30). In the use process of the liquid metal electromagnetic pump 100 of the embodiment of the present application, the liquid metal with high temperature is driven by the electromagnetic driving device to flow into the passage of the liquid flow pipeline 30 from the liquid flow inlet and flow out from the liquid flow outlet, so as to realize the pumping action on the liquid metal.

In particular, the inner diameter of the inner passage of the liquid flow pipe 30 is uniformly set. That is, the inner surface of the flow conduit 30 defines a cylindrical passage of uniform diameter. This application embodiment arranges into along vertical extension through liquid flow pipeline 30 for liquid metal electromagnetic pump 100 wholly uses vertical layout structure, and further sets up the passageway in liquid flow pipeline 30 into the even straight barrel-type passageway of internal diameter, has solved the hydrops and the long-pending gas problem of liquid metal electromagnetic pump 100 of horizontal overall arrangement, has promoted the security that liquid metal electromagnetic pump 100 maintained and changed by a wide margin, has improved the job stabilization nature of liquid metal electromagnetic pump 100 and the reliability of long-term running.

In some embodiments, referring to fig. 1, the electromagnetic drive device may comprise: an outer core disposed radially outward of the flow conduit 30 and a plurality of coils 10. The outer core extends vertically (i.e., lengthwise, or axially, of the flow conduit 30) radially outward of the flow conduit 30.

The outer core is provided with a plurality of winding slots in a vertical direction (i.e., the length direction of the outer core, or axial direction). The coil 10 is sleeved on the radial outer side of the liquid flow pipeline 30. Each coil 10 is arranged in one winding slot of the outer core.

The flow conduit 30 also typically has a relatively high temperature due to the liquid metal flowing into the flow conduit 30 being at a relatively high temperature. Referring to fig. 6 and 7, an insulation layer 70 may be disposed between the outer core and the flow conduit 30 to reduce heat transfer therebetween so as to prevent excessive temperatures of the outer core and the coil 10. In some embodiments, the material of the thermal insulation layer 70 may be a high temperature resistant nano-insulation material.

The coil 10 may be formed by winding a wire having an insulating layer on a surface thereof in a radial direction into a hollow disk-shaped structure. The number of the winding slots and the coils 10 can be integral multiples of 3, the coils 10 adopt a triangular circuit connection method, the coils 10 are electrified with variable currents with phase difference of 120 degrees, and the generated travelling wave magnetic field acts on the liquid metal medium to push the liquid metal to flow in the liquid flow pipeline 30.

In particular, in some embodiments, referring to fig. 1-4, the side of the outer core away from the flow conduit 30 (i.e., the radially outer side) is provided with a heat dissipation structure 22 to increase the heat dissipation area of the outer core. The space condition of natural convection heat exchange can be improved by providing the heat dissipation structure 22 facilitating heat dissipation into the air at the radially outer side of the outer core.

In some embodiments, the heat dissipation structure 22 is a plurality of heat dissipation fins extending vertically downward from the upper end of the outer core to the lower end of the outer core. That is to say, set up a plurality of vertical extended radiating fin on the whole length direction of outside iron core to can show the heat radiating area who increases outside iron core and obviously improve natural convection heat transfer's spatial condition, further reduce the fault rate of liquid metal electromagnetic pump. Through the design, the external iron core can be effectively radiated only by natural convection on the premise that the magnetic conductivity of the external iron core is not influenced.

In some embodiments, referring to fig. 1 to 3, the outer core includes a plurality of bar cores 20 extending in a vertical direction, the bar cores 20 are arranged at intervals along a circumferential direction of the liquid flow pipe 30 at radial outer sides thereof, each bar core 20 is provided with a plurality of core slots 21 in the vertical direction, and the core slots 21 of the bar cores 20 at the same vertical position together constitute one winding slot of the outer core.

In some embodiments, the number of the bar-shaped iron cores 20 may be an even number, and the even number of the bar-shaped iron cores 20 are uniformly distributed in the circumferential direction on the radial outer side of the flow conduit 30 (i.e., the bar-shaped iron cores 20 are arranged at equal intervals in the circumferential direction on the radial outer side of the flow conduit 30) so as to form a symmetrical magnetic field. In the illustrated embodiment, the number of the bar-shaped iron cores 20 is 8, and the 8 bar-shaped iron cores 20 are uniformly distributed in the circumferential direction on the radial outer side of the liquid flow pipe 30. In other embodiments, the number of the strip-shaped iron cores 20 may also be 4, 6, 10, etc.

Referring to fig. 1 to 4, in some embodiments, a side of each bar core 20 away from the liquid flow pipe 30 (or a side away from the core slot 21) is provided with a heat dissipation structure 22 to increase a heat dissipation area of the bar core 20. That is, the heat dissipation structure 22 facilitating heat dissipation into the air is provided on the radially outer surface of the bar-shaped iron core 20, thereby improving the spatial condition of natural convection heat transfer by increasing the heat dissipation area of the bar-shaped iron core 20.

In some embodiments, the bar-shaped iron core 20 may be laminated from non-oriented silicon steel sheets. In some embodiments, the bar-shaped iron core 20 with the heat radiating fins may be composed of silicon steel sheets having the same vertical dimension but two widths in the radial direction stacked together. An iron core open slot 21 is opened on one side of the silicon steel sheet close to the liquid flow pipe 30, and the opposite side (i.e. the side far away from the iron core open slot 21) is overlapped to form the heat dissipation fin through the width difference of the silicon steel sheet. Specifically, for example, a first number of narrow silicon steel sheets may be stacked, a second number of wide silicon steel sheets may be stacked on the narrow silicon steel sheets, and the first number of narrow silicon steel sheets may be stacked, and so on, until a complete strip-shaped iron core 20 is stacked. These narrow silicon steel sheets and wide silicon steel sheets collectively form the strip-shaped iron core 20 having the aforementioned heat radiating fins. Wherein the first number and the second number may be the same or different. In some embodiments, the first number and the second number may be selected from 10 to 20.

Referring to fig. 5-11, in some embodiments, the electromagnetic drive further comprises: a housing 60 disposed radially inward of the fluid flow conduit 30, and an inner core 50 disposed inside the housing 60.

The housing 60 is provided with a housing mount to be vertically disposed within the passage of the fluid flow conduit 30 therethrough. The interior of the housing 60 forms a sealed chamber with an annular flow passage for liquid metal communication communicating with the upper and lower end openings formed between the outer surface of the housing 60 and the inner surface of the flow conduit 30 (see fig. 11).

Referring to fig. 8 and 9, the casing 60 includes a first guide section 61 with a gradually expanding inner diameter, a sleeve section 63 with a uniform inner diameter, and a second guide section 62 with a gradually contracting inner diameter, which are connected in sequence from bottom to top. The first flow guiding section 61, the sleeve section 63 and the second flow guiding section 62 are welded to each other to form a closed chamber inside the casing 60. Therefore, the annular flow channel jointly constructed by the casing 60 and the liquid flow pipeline 30 is a gradual change annular flow channel with guidance, the annular flow channel can reduce the flow resistance of the liquid metal as much as possible, the flow threshold corresponding to the fluid cavitation vibration phenomenon is improved, and the fluid stability when the liquid metal electromagnetic pump 100 drives the high-temperature liquid metal, especially the alkali metal such as sodium and potassium, is greatly improved.

Referring to fig. 6 and 8, in some embodiments, the housing mounting portion includes a plurality of welds 65 to mount the housing 60 within the passage of the flow conduit 30 by welding. In some embodiments, a plurality of welds 65 are provided on the second flow guide section 62. In some embodiments, weld 65 extends obliquely upward from second flow guide section 62 toward flow conduit 30. In other embodiments, the weld 65 may be a protrusion extending radially toward the flow conduit 30.

In some embodiments, the housing mounting portion may further include a plurality of supports 66 disposed radially outward of the first inducer 61 in sliding (or clearance) engagement with the inner surface of the flow conduit 30. In the embodiment of the present application, the casing 60 is welded and fixed to the upper portion of the flow pipe 30 by the welding portion 65, and the support portion 66 is slidably fitted to the lower portion of the flow pipe 30, so that the casing section 63 is prevented from buckling due to the gravity and the axial differential pressure load, and the operational reliability of the casing 60 is ensured.

In an alternative embodiment, the welding portion 65 may be provided at an upper portion of the case 60, and the supporting portion 66 is provided at a middle or lower portion of the case 60; alternatively, the welding portion 65 may be provided at a lower portion of the case 60, and the supporting portion 66 may be provided at an upper or middle portion of the case 60.

In some embodiments, an inner support tube 64 and a flexible portion 67 are also provided within the sealed chamber of the housing 60. The inner support pipe 64 is vertically disposed in the closed chamber of the housing 60, and the inner core 50 is closely fitted over a radially outer side of the inner support pipe 64. As will be readily understood by those skilled in the art, the "close fitting" herein means that no relative displacement occurs between the inner core 50 and the inner support tube 64, and the radially inner side surface of the inner core 50 is in close contact with the radially outer side surface of the inner support tube 64, thereby forming good thermal contact between the inner core 50 and the inner support tube 64.

The first and second flow guide sections 61 and 62 may be provided with grooves for receiving the inner support tubes 64, and the inner support tubes 64 may be spaced apart from the first and/or second flow guide sections 61 and 62 after being mounted in the grooves of the first and second flow guide sections 61 and 62. The elastic part 67 is disposed at the bottom of the inner support pipe 64 and is located in the groove of the first guide section 61 for providing an upward elastic force to allow the upper end of the inner support pipe 64 to contact the housing 60 at different temperatures. Contact here should be understood as an effective heat transfer between the support tube 64 and the housing 60. That is, when the housing 60 and the inner support tube 64 have different expansion and contraction amounts due to temperature change, the elastic portion 67 may always make close contact between the inner support tube 64 and the first flow guiding section 61 by changing the compression amount thereof. In some embodiments, the elastic portion 67 is a thermal compensation spring, which can achieve effective transfer of the induction heat by ensuring a gapless close contact between the inner support tube 64 and the first flow guiding section 61, thereby avoiding the problem of induction heat accumulation.

With the inner core 50 disposed within the flow conduit 30, it is difficult to effectively dissipate heat from the inner core 50 because it is inside the sealed housing 60, and the housing 60 is inside the high temperature liquid metal. The prior art generally utilizes a means of reducing the temperature of the liquid metal to prevent high temperature demagnetization of the inner core 50. That is, the related art does not consider the improvement of the structure of the inner core 50. The inventors of the present application have found that, in some cases, the internal heat is not efficiently conducted due to the temperature unevenness in the internal portion of the internal core 50, and the problem of local heat accumulation is caused, thereby causing high-temperature demagnetization in the partial structure of the internal core 50.

Therefore, in some embodiments of the present application, especially the housing 60 is internally provided as a vacuum chamber, the inner core 50 is vertically provided in the vacuum chamber, and at least a part of the outer surface of the inner core 50 is closely attached to the radially inner surface of the housing 60. Through setting up like this, can guarantee casing 60 and inside iron core 50 inseparable effective contact under high temperature, improve the conduction efficiency of heat between inside iron core 50 and casing 60, be favorable to reducing inside iron core 50 and take place high temperature and lose magnetism.

In some embodiments, all of the outer surfaces of the inner core 50 are in close proximity to the radially inner surface of the housing 60. That is, the radially outer surface and the axially outer surface of the inner core 50 are closely attached to the radially inner surface of the housing 60, and the efficiency of heat conduction between the inner core 50 and the housing 60 is further improved.

In some embodiments, inner core 50 is located inside of sleeve segment 63. Casing section 63 is configured to: can be deformed inwards under the effect of the pressure difference between the inner side and the outer side thereof so as to be closely attached to the radial outer surface of the inner core 50, thereby improving the heat conduction efficiency between the inner core 50 and the shell 60.

In some embodiments, the inner core 50 may be formed by stacking a plurality of silicon steel sheets in a circumferential direction on the radially outer side of the inner support tube 64. Subject to the limitations of the manufacturing process, in some embodiments, the inner core 50 may be comprised of a plurality of segmental cores surrounding the outside of the inner support tube 64. Each fan-shaped iron core is formed by tightly laminating a plurality of silicon steel sheets along the circumferential direction. Note that the specific form of the inner core 50 is not limited to this. In other embodiments, inner core 50 may have other configurations as are commonly used in the art.

Referring to FIG. 1, in some embodiments, the liquid metal electromagnetic pump 100 may further include: and the upper mounting assembly and the lower mounting assembly are respectively arranged at the upper end and the lower end of the plurality of strip-shaped iron cores 20 and are used for mounting the liquid flow pipeline 30 and the plurality of strip-shaped iron cores 20 together.

Upper portion installation component and lower part installation component all include: a first mounting portion 41 and a second mounting portion 42. In some embodiments, the first and second mounting portions 41, 42 may each be made of an austenitic stainless steel material.

The first mounting portion 41 is provided with a first center hole 413 through which the liquid flow pipe 30 passes, and one axial end of each of the bar cores 20 is connected to the first mounting portion 41. Referring to fig. 5 to 7, the upper and lower ends of the bar-shaped iron core 20 are respectively provided with a mounting member 23, the mounting member 23 is provided with a mounting hole, and the two ends of the bar-shaped iron core 20 are correspondingly mounted on the upper and lower first mounting portions 41 through the first fastening member 44.

The second mounting portion 42 is provided with a second central hole for the liquid flow pipe 30 to pass through, and the second mounting portion 42 is connected with the liquid flow pipe 30 and fixedly connected with the first mounting portion 41 at one side of the first mounting portion 41 far away from the bar-shaped iron core 20.

Specifically, the upper and lower ends of each bar-shaped iron core 20 are fixedly connected to the first mounting portion 41 of the upper mounting component and the first mounting portion 41 of the lower mounting component, respectively, so that the bar-shaped iron core 20, the upper and lower first mounting portions 41 are assembled into a whole.

For the upper mounting assembly, its second mounting portion 42 is fixedly connected to the first mounting portion 41 above its first mounting portion 41 by fasteners 45. For the lower mounting assembly, its second mounting portion 42 is fixedly connected to the first mounting portion 41 by fasteners 45 below its first mounting portion 41. Thus, the bar-shaped iron core 20, the upper and lower first mounting portions 41, and the upper and lower second mounting portions 42 are assembled as a single body.

The upper end of the liquid flow pipe 30 passes through the first central hole 413 of the first mounting part 41 and the second central hole of the second mounting part 42 of the upper mounting assembly in sequence to be connected with the second mounting part 42; the lower end of the liquid flow pipe 30 passes through the first central hole 413 of the first mounting part 41 and the second central hole of the second mounting part 42 of the lower mounting assembly in sequence to be connected with the second mounting part 42; thus, the liquid flow tube 30, the bar-shaped iron core 20, the two upper and lower first mounting portions 41, and the two upper and lower second mounting portions 42 are assembled as a single body.

There is no direct contact between the fluid flow pipe 30 and the first mounting portion 41, that is, the fluid flow pipe 30 only passes through the first central hole 413 of the first mounting portion 41, but does not contact the peripheral wall of the first central hole 413, that is, there is a gap between the fluid flow pipe 30 and the first central hole 413, so as to prevent heat from being directly conducted from the fluid flow pipe 30 to the first mounting portion 41 and then conducted to the bar-shaped iron core 20 via the first mounting portion 41.

Referring to fig. 6, 7 and 12, the liquid flow pipe 30 includes an inlet section 31 at a lower end, an outlet section 32 at an upper end, and a middle connecting section 33 connecting the inlet section 31 and the outlet section 32, wherein the outlet section 32 is provided with an outwardly protruding catch 321. In such an embodiment, the lower end opening of the flow conduit 30 serves as a flow inlet for receiving the inflow of liquid metal, and the upper end opening serves as a flow outlet for delivering the liquid metal outwardly.

Referring to fig. 6, when the fluid flow pipe 30 is assembled with the bar-shaped iron core 20, the upper and lower first mounting parts 41, and the upper and lower second mounting parts 42 as a whole, the catching part 321 is positioned above the first mounting part 41 of the upper mounting assembly, and the outer diameter of the catching part 321 is larger than the inner diameter of the first central hole 413, so that the fluid flow pipe 30 is supported by the first mounting part 41 by the catching of the catching part 321 with the first central hole 413.

In some embodiments, the catch 321 fits into the second central hole of the second mounting portion 42 of the upper mounting assembly, wherein the radially outer surface of the catch 321 includes a first inclined surface that tapers from top to bottom, and the radially inner surface of the second central hole includes a second inclined surface that tapers from top to bottom, thereby securing the catch 321 with the upper mounting assembly by the cooperation of the second inclined surface and the first inclined surface. Specifically, when the second mounting portion 42 is fixedly coupled to the first mounting portion 41 using the fastener 45, the second inclined surface of the second mounting portion 42 clamps the catch 321 between the second mounting portion 42 and the first mounting portion 41 (i.e., fixed to the upper mounting assembly).

In some embodiments, referring to fig. 7 and 12, the inlet section 31 is provided with a limiting portion 311 having an outer diameter larger than that of the middle connecting section 33, and the flow conduit 30 is slidably fitted (or clearance fitted) with the second central hole of the second mounting portion 42 of the lower mounting assembly through the limiting portion 311. In these embodiments, the liquid flow pipe 30 is fixed to the upper mounting component by the retaining portion 321 at the upper portion of the liquid flow pipe 30, and the liquid flow pipe 30 is slidably fitted to the lower mounting component by the limiting portion 311 at the lower portion of the liquid flow pipe 30; the connection mode can avoid the problem of thin shell buckling possibly induced by the action of gravity and axial differential pressure load on the liquid flow pipeline 30, and ensures the operation reliability of the liquid flow pipeline 30.

Those skilled in the art will readily understand that the peripheral walls of the inlet section 31 and the outlet section 32 of the liquid flow pipe 30 are thicker and are respectively provided with a retaining part 321 and a limiting part 311 for supporting and fixing the liquid flow pipe 30; however, the inner holes of the inlet section 31, the outlet section 32 and the middle connecting section 33 are all smooth round holes with consistent diameters and have no diameter change.

The heat insulating layer 70 is held between the holding portion 321 and the stopper portion 311, and supported by the stopper portion 311 to prevent the heat insulating layer 70 from moving downward.

Referring to fig. 13 and 14, in some embodiments, a plurality of first heat dissipation holes 411 are provided radially outside the first mounting portion 41, wherein a projection of the heat dissipation structure 22 of each strip-shaped iron core 20 on the first mounting portion 41 is located inside one of the first heat dissipation holes 411. That is to say, the upper side and the lower side of the heat dissipation structure 22 of each strip-shaped iron core 20 correspond to one first heat dissipation hole 411 of the first mounting portion 41 respectively, so that a plurality of ideal longitudinal air circulation paths are constructed by the first heat dissipation holes 411 and the heat dissipation structure (such as the heat dissipation fins described above) of the strip-shaped iron core 20 together, and the vertical layout of the liquid metal electromagnetic pump 100 provides a sufficient longitudinal flow development space, which further improves the efficiency of natural convection heat exchange of air, thereby greatly improving the heat dissipation performance of the liquid metal electromagnetic pump 100. Experiments show that, compared with the liquid metal electromagnetic pump 100 with the horizontal layout, the liquid metal electromagnetic pump 100 with the vertical layout, which is provided with the first heat dissipation hole 411 and the heat dissipation structure 22 according to the embodiment of the present application, can reduce the temperature of the coil 10 by about 50 ℃, so that the service life of the coil 10 of the liquid metal electromagnetic pump 100 can be greatly prolonged.

Further, a plurality of second heat dissipation holes 412 may be disposed at the radial outer side of the first mounting portion 41, and the second heat dissipation holes 412 and the first heat dissipation holes 411 are disposed at intervals, so as to further improve the heat dissipation effect of the bar-shaped iron core 20. As shown in fig. 13 and 14, the plurality of first heat dissipation holes 411 are disposed at equal intervals in the radial direction outside of the first mounting portion 41, and each second heat dissipation hole 412 is disposed in the middle of two first heat dissipation holes 411, so that the heat dissipation of the first mounting portion 41 and the bar core 20 is more uniform.

In some embodiments, referring to fig. 4 and 5, a thermal insulating spacer 43 is further disposed between the first mounting portion 41 and the second mounting portion 42 for reducing heat transfer therebetween.

Referring to fig. 14, for the lower mounting assembly, a plurality of support legs 40 may be further provided at the bottom of the first mounting portion 41 to raise the liquid metal electromagnetic pump 100 as a whole upward, thereby further facilitating heat dissipation from the coil 10 and the bar-shaped iron core 20.

Referring to fig. 15 and 16, in some embodiments, a side surface of the second mounting portion 42 facing the first mounting portion 41 is formed with a protrusion 422 protruding toward the first mounting portion 41, and the second mounting portion 42 is in contact with the first mounting portion 41 through the protrusion 422. Therefore, the contact area between the second mounting portion 42 and the first mounting portion 41 can be reduced as much as possible, and heat transfer from the second mounting portion 42 to the first mounting portion 41 can be reduced as much as possible, so that a large amount of heat is not transferred to the bar core 20 via the first mounting portion 41.

In some embodiments, the boss 422 is an annular flange formed at the periphery of the second mounting portion 42. In other embodiments, the raised portions 422 are a plurality of projections formed on the second mounting portion 42 at circumferentially spaced intervals.

In some embodiments, a plurality of ribs 423 are provided on a contact surface of the boss 422 and the first mounting portion 41. The second mounting portion 42 is in contact with the first mounting portion 41 through the ribs 423, thereby further reducing a contact area of the second mounting portion 42 with the first mounting portion 41. The ribs 423 may extend in a circumferential direction, and a V-groove may be formed between adjacent two of the ribs 423.

In some embodiments, the circumferential edge of the second mounting portion 42 is formed with a plurality of mounting portion slots 421 to attenuate thermal stresses caused by radial thermal gradients. Referring to fig. 13, the second mounting portion 42 is fixedly coupled to the first mounting portion 41 with a fastener 45 passing through the mounting portion slot 421. This application embodiment carries out special design (like bellying and installation department fluting) through the structure to second installation department 42 for second installation department 42 possesses excellent thermal adaptability and thermal-insulated ability, both can be directly closely cooperate and do not produce big thermal stress with high temperature flow pipeline 30, thereby guarantee the firm support to flow pipeline 30, can effectively alleviate the heat-conduction of high temperature liquid metal to outside iron core and coil 10 again, further reduced the fault rate of liquid metal electromagnetic pump 100.

It will be readily understood by those skilled in the art that the first central bore 413 of the first mounting portion 41 of the upper and lower mounting assemblies has an inner diameter greater than the outer diameter of the intermediate connecting section 33 in order to avoid contact of the first mounting portion 41 with the fluid flow conduit 30. The first mounting portions 41 of the upper and lower mounting assemblies may have identical structures. The second central hole of the second mounting portion 42 of the upper mounting assembly needs to be matched with the retaining portion 321, so the size and shape of the second central hole are different from those of the second central hole of the second mounting portion 42 of the lower mounting assembly, but other structures such as the mounting portion slot 421, the protruding portion 422 and the rib 423 are the same.

In assembling the liquid metal electromagnetic pump 100, the inner core 50 may be first installed in the outer casing 60, and then the outer casing 60 may be evacuated to make the inside of the outer casing a vacuum environment. The housing 60 is then welded in the passage of the flow conduit 30 by the weld 65.

The second mounting portion 42 of the upper mounting assembly is sleeved from the upper end (i.e., the outlet section 32) of the liquid flow pipe 30 to the outlet section of the liquid flow pipe 30 and is matched with the retaining portion 321, the first mounting portion 41 of the upper mounting assembly is sleeved from the lower end (i.e., the inlet section 31) of the liquid flow pipe 30 to the lower portion of the retaining portion 321 of the liquid flow pipe 30, and the second mounting portion 42 and the first mounting portion 41 are assembled through the fastening member 45.

Then, the coil 10 is fitted over the middle connection section 33 of the liquid flow pipe 30, and the upper end of the bar-shaped iron core 20 is connected to the first mounting portion 41 of the upper mounting assembly by the first fastening member 44.

Then, the first mounting part 41 and the second mounting part 42 of the lower mounting assembly are sequentially sleeved to the inlet section 31 of the liquid flow pipeline 30 from the lower end of the liquid flow pipeline 30, the first mounting part 41 is connected with the lower end of the strip-shaped iron core 20 through a first fastener 44, and the second mounting part 42 and the first mounting part 41 are assembled through a fastener 45. Thus, the upper and lower mounting assemblies, the flow tube 30 (including the housing 60 and the inner core 50), and the bar core 20 and the coil 10 are collectively assembled into a unitary liquid metal electromagnetic pump 100.

According to the embodiment of the application, the failure rate of the liquid metal electromagnetic pump 100 can be obviously reduced through the scheme, and the method is particularly suitable for special application scenes (such as severe environments of nuclear power plants and the like) with high medium temperature and high reliability requirements.

It should also be noted that, in the case of the embodiments of the present invention, features of the embodiments and examples may be combined with each other to obtain a new embodiment without conflict.

The above description is only an embodiment of the present invention, but the scope of the present invention is not limited thereto, and the scope of the present invention is subject to the scope of the claims.

Claims (16)

1. A liquid metal electromagnetic pump, comprising:

a liquid flow pipe (30) extending vertically and defining a passage therein having a uniform inner diameter and having openings at upper and lower ends; and

an electromagnetic drive device for providing an electromagnetic force for driving liquid metal to flow into the channel from one end opening of the flow conduit (30) and to flow out through the other end opening of the flow conduit (30), the electromagnetic drive device comprising:

the outer iron core extends along the vertical direction at the radial outer side of the liquid flow pipeline (30), and is provided with a plurality of winding grooves along the vertical direction; and

a plurality of coils (10) sleeved on the radial outer side of the liquid flow pipeline (30), wherein each coil (10) is arranged in one winding groove of the outer iron core;

a heat dissipation structure (22) is arranged on one side, away from the liquid flow pipeline (30), of the external iron core so as to increase the heat dissipation area of the external iron core;

the external iron core comprises a plurality of strip-shaped iron cores (20) extending vertically, the strip-shaped iron cores are arranged at intervals along the circumferential direction of the liquid flow pipeline (30) at the radial outer side of the liquid flow pipeline, a plurality of iron core slots (21) are vertically arranged on one side, facing the liquid flow pipeline (30), of each strip-shaped iron core (20), and the iron core slots (21) of the plurality of strip-shaped iron cores (20) at the same vertical position jointly form one winding slot; wherein

One side, far away from the liquid flow pipeline (30), of each strip-shaped iron core (20) is provided with the heat dissipation structure (22);

the liquid metal electromagnetic pump further comprises: an upper mounting assembly and a lower mounting assembly respectively disposed at upper and lower ends of the plurality of bar cores (20) for mounting the liquid flow pipe (30) and the plurality of bar cores (20) together, wherein the upper mounting assembly and the lower mounting assembly each include:

a first mounting part (41) provided with a first central hole (413) for the liquid flow pipeline (30) to pass through, and one axial end of each strip-shaped iron core (20) is connected with the first mounting part (41); and

the second mounting part (42) is provided with a second central hole for the liquid flow pipeline (30) to pass through, the second mounting part (42) is connected with the liquid flow pipeline (30), and is connected with the first mounting part (41) on one side of the first mounting part (41) far away from the strip-shaped iron core (20);

the liquid flow pipe (30) comprises an inlet section (31) at a lower end, an outlet section (32) at an upper end, and a middle connecting section (33) connecting the inlet section (31) and the outlet section (32), wherein the outlet section (32) is provided with an outwardly protruding catch (321),

The clamping part (321) is arranged above the first mounting part (41) of the upper mounting assembly, the outer diameter of the clamping part (321) is larger than the inner diameter of the first central hole, and the liquid flow pipeline (30) is supported by the first mounting part (41) in a clamped mode through the clamping part (321) and the first central hole.

2. The liquid metal electromagnetic pump of claim 1, wherein the heat dissipating structure (22) is a plurality of heat dissipating fins extending vertically downward from an upper end of the outer core to a lower end of the outer core.

3. The liquid metal electromagnetic pump of claim 1, wherein the catch (321) is fitted into the second central bore of the upper mounting assembly, wherein a radially outer surface of the catch (321) includes a first inclined surface that is tapered from top to bottom, and a radially inner surface of the second central bore includes a second inclined surface that is tapered from top to bottom, such that the catch (321) is fixed to the upper mounting assembly by engagement of the second inclined surface and the first inclined surface.

4. A liquid metal electromagnetic pump according to claim 1, wherein the inlet section (31) is provided with a limiting portion (311) having an outer diameter larger than the intermediate connecting section (33), and the flow conduit (30) is in sliding engagement with the second central bore of the second mounting portion (42) of the lower mounting assembly via the limiting portion (311).

5. The liquid metal electromagnetic pump according to claim 4, wherein a heat insulation layer (70) is further disposed between the plurality of bar-shaped iron cores (20) and the liquid flow pipe (30), and the heat insulation layer (70) is clamped between the clamping portion (321) and the limiting portion (311).

6. The electromagnetic pump for liquid metal according to claim 1, characterized in that a plurality of first heat dissipation holes (411) are provided radially outside the first mounting portion (41), wherein a projection of the heat dissipation structure (22) of each bar-shaped iron core (20) on the first mounting portion (41) is located inside one of the first heat dissipation holes (411).

7. The electromagnetic pump for liquid metal as claimed in claim 6, wherein a plurality of second heat dissipation holes (412) are further disposed radially outside the first mounting portion (41), and the second heat dissipation holes (412) and the first heat dissipation holes (411) are spaced apart from each other.

8. A liquid metal electromagnetic pump according to claim 1, wherein a side surface of the second mounting portion (42) facing the first mounting portion (41) is formed with a projection portion (422) projecting toward the first mounting portion (41), and the second mounting portion (42) is in contact with the first mounting portion (41) through the projection portion (422).

9. The liquid metal electromagnetic pump of claim 8, wherein the boss (422) is an annular flange formed on a periphery of the second mount portion (42).

10. A liquid metal electromagnetic pump according to claim 8, wherein a plurality of ribs (423) are provided on a contact surface of the boss (422) with the first mounting portion (41).

11. The electromagnetic pump for liquid metal as claimed in claim 8, characterized in that the second mounting portion (42) has a plurality of mounting portion slots (421) formed in a circumferential edge thereof;

the second mounting portion (42) is fixedly connected with the first mounting portion (41) by a fastener (45) penetrating through the mounting portion slot (421).

12. A liquid metal electromagnetic pump according to claim 1, wherein a thermally insulating spacer (43) is also provided between the first mounting portion (41) and the second mounting portion (42) to reduce heat transfer therebetween.

13. A liquid metal electromagnetic pump as claimed in claim 1, wherein said electromagnetic drive further comprises:

a housing (60) provided with a housing mounting part to be vertically arranged in the passage of the liquid flow pipeline (30) through the housing mounting part, a vacuum chamber is formed inside the housing (60), and an annular flow passage communicated with openings at the upper and lower ends of the liquid flow pipeline (30) and allowing liquid metal to flow is formed between the outer surface of the housing (60) and the inner surface of the liquid flow pipeline (30); and

An inner core (50) vertically disposed in the vacuum chamber, and at least a portion of an outer surface of the inner core (50) is in close contact with a radially inner surface of the housing (60).

14. The electromagnetic liquid metal pump of claim 13, wherein the casing (60) includes a first flow guide section (61) with a gradually expanding inner diameter, a sleeve section (63) with a uniform inner diameter, and a second flow guide section (62) with a gradually contracting inner diameter, which are connected in sequence from bottom to top,

the casing section (63) is configured to: the inner core (50) and the outer core (60) can deform inwards under the action of pressure difference between the inner side and the outer side so as to be tightly attached to the radial outer surface of the inner core (50), and therefore the heat conduction efficiency between the inner core (50) and the shell (60) is improved.

15. The liquid metal electromagnetic pump of claim 14, wherein the housing mounting portion comprises:

a plurality of welds (65) disposed on the second flow guide section (62) to install the housing (60) in the passage of the flow conduit (30) by welding; and

a plurality of support portions (66) disposed radially outward of the first inducer (61) in sliding engagement with an inner surface of the flow conduit (30).

16. A liquid metal electromagnetic pump according to claim 13, wherein the vacuum chamber of the housing (60) further has disposed therein:

a vertically extending inner support tube (64); and

an elastic part (67) provided at the bottom of the inner support pipe (64) for providing an upward elastic force to enable the upper end of the inner support pipe (64) to be in contact with the housing (60) at different temperatures; wherein

The inner iron core (50) is tightly sleeved on the radial outer side of the inner support pipe (64).

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