Mechanism and method for measuring flow velocity distribution of liquid metal in magnetic field

Abstract

The invention discloses a mechanism and a method for measuring flow velocity distribution of liquid metal in a magnetic field, and relates to the technical field of liquid metal flow state measurement. The measuring mechanism comprises a connecting joint which is used for being connected with a measuring interface corresponding to a pipeline to be measured, and the connecting joint can be used for sealing and movably inserting a potential probe; the thread adjusting assembly is fixedly connected with the connecting joint, the thread adjusting assembly is used for driving the potential probe to move in the axial direction of the connecting joint so as to prevent liquid metal in the to-be-measured pipeline from leaking in the measuring process, and meanwhile the thread adjusting assembly is fixedly connected with the connecting joint so as to adjust the liquid metal in the to-be-measured pipeline. And the driving device can drive the potential probe to move along the axial direction of the connecting joint so as to accurately control the axial displacement of the potential probe through the thread pair, so that the potential probe is continuously moved to measure different positions for multiple times, and flow velocity distribution data on a linear path from the pipe wall of the to-be-measured pipeline to the central area are obtained. The measuring method is based on the liquid metal flow velocity distribution measuring mechanism in the magnetic field.

Description

Technical Field

[0001] The invention relates to the technical field of liquid metal flow measurement, and in particular to a liquid metal flow velocity distribution measurement mechanism and a measurement method in a magnetic field. Background Art

[0002] Liquid blanket is one of the main candidates for fusion reactor blanket. The liquid metal in the liquid blanket channel moves in the strong magnetic field of the magnetic confinement fusion reactor, and the Lorentz force will significantly change its flow state, that is, produce a very strong magnetohydrodynamic (MHD) effect. Therefore, accurate measurement of the liquid metal flow velocity distribution is of great significance to the study of MHD effect and the development of liquid blanket. However, due to the high temperature, strong corrosion, opacity of liquid metal and the strong magnetic field environment in the reactor, many traditional flow velocity measurement technologies are difficult to obtain good results or even difficult to achieve in MHD experiments.

[0003] In the prior art, the flow velocity distribution of liquid metal is usually measured by potential probe measurement. By collecting the potential difference of the probe electrode and the strength of the external magnetic field, the flow velocity of the liquid metal at the measurement point can be converted according to the law of electromagnetic induction. It has a simple structure, small size, and minimal impact on the fluid itself. It is mainly used for the flow velocity measurement of liquid metal in MHD experiments. When using potential detection to measure the flow velocity distribution of liquid metal, it is necessary to control the movement of the potential probe in the liquid metal flow pipe to measure the flow velocity distribution data of the liquid metal at different positions. However, the existing potential probe installation structure cannot meet the needs of liquid metal MHD effect research. Summary of the invention

[0004] In view of the technical problem that the existing potential probe installation structure cannot meet the needs of liquid metal MHD effect research, the present invention provides a liquid metal flow velocity distribution measurement mechanism and measurement method in a magnetic field, which can seal the gap between the potential probe and the liquid metal flow pipeline and accurately control the displacement of the potential probe to accurately measure the flow velocity distribution data of the liquid metal to meet the needs of liquid metal MHD effect research.

[0005] The present invention is achieved through the following technical solutions:

[0006] In the first aspect, the present invention provides a mechanism for measuring the flow velocity distribution of liquid metal in a magnetic field, comprising: a connecting joint, which is used to connect the measurement interface corresponding to the pipeline to be measured, and the connecting joint can be sealed and movably inserted with a potential probe; a threaded adjustment assembly, which is fixedly connected to the connecting joint, and the threaded adjustment assembly is used to drive the potential probe to move axially along the connecting joint.

[0007] It should be noted that in liquid metal MHD experiments, it is generally necessary to extract the liquid metal velocity distribution data at different positions on the path from the pipe wall to the center of the pipe, and a mechanism is needed to cooperate with the installation of the potential probe. The connection between the mechanism and the probe must be firm and the seal must be reliable to effectively prevent the leakage of liquid metal in the cladding channel and ensure the safety and stability of the experimental operation; it is also necessary to achieve precise adjustment of the probe measurement position after the mechanism is connected to the potential probe. At present, there is a lack of devices that meet the above requirements at the same time in the relevant field. Therefore, in order to meet the research needs of the liquid metal MHD effect and other related fields, it is necessary to develop a special mechanism for measuring the liquid metal velocity distribution in a strong magnetic environment in conjunction with the connection of a potential probe.

[0008] In view of this, the present invention provides a liquid metal flow velocity distribution measurement mechanism in a magnetic field, including a connecting joint and a threaded adjustment assembly. The connecting joint can be sealed and a potential probe can be movably inserted to prevent leakage of liquid metal in the pipeline to be measured during the measurement process. At the same time, the threaded adjustment assembly is fixedly connected to the connecting joint and can drive the potential probe to move axially along the connecting joint to accurately control the axial displacement of the potential probe through the threaded pair, thereby performing multiple measurements at different positions by continuously moving the potential probe to obtain flow velocity distribution data on a straight path from the pipe wall to the center area of ​​the pipeline to be measured.

[0009] The liquid metal flow velocity distribution measuring mechanism in a magnetic field provided by the present invention can seal the gap between the potential probe and the liquid metal flow pipeline, and can accurately control the displacement of the potential probe to accurately measure the flow velocity distribution data of the liquid metal, thereby meeting the needs of liquid metal MHD effect research.

[0010] In an optional embodiment of the present application, it also includes a potential probe body, the rod portion of the potential probe body is movably inserted in the connecting joint, and the potential probe body is transmission-connected to the threaded adjustment assembly, so that the liquid metal flow velocity distribution measurement mechanism in the magnetic field can directly measure the liquid metal flow velocity distribution in the magnetic field.

[0011] In an optional embodiment of the present application, a sealing cap is fixedly adapted inside the connecting joint, and the sealing cap is sealingly connected to the connecting joint; the sealing cap is sleeved outside the rod portion of the potential probe body, and the sealing cap is adapted to be equipped with a first sealing ring, and the first sealing ring is used to seal the gap between the sealing cap and the rod portion of the potential probe body to ensure that the connecting joint can be sealed and the potential probe can be movably inserted.

[0012] In an optional embodiment of the present application, the threaded adjustment assembly includes: a mounting frame, which is fixedly connected to the connecting joint; a guide frame, which is slidably connected to the mounting frame, the guide frame can move along the axial direction of the connecting joint, and the guide frame is fixedly connected to the potential probe body; an adjusting nut, the adjusting nut is mounted on the mounting frame, and the adjusting nut can rotate along its own axis; an adjusting screw, the adjusting screw is threadedly connected to the adjusting nut, the adjusting screw is fixedly connected to the potential probe body, and the adjusting screw is sleeved outside the potential probe body to drive the guide frame to move by rotating the adjusting nut, thereby accurately controlling the axial displacement of the potential probe through the threaded pair.

[0013] In an optional embodiment of the present application, the mounting frame includes: a first fixing plate, which is fixedly connected to the connecting joint; a second fixing plate, which is used to install the adjusting nut; a guide rod, which is provided with a plurality of guide rods, and the two ends of the guide rods are respectively fixedly connected to the first fixing plate and the second fixing plate, and the guide rods are arranged in the guide frame to ensure that the guide frame can move smoothly along the axis of the connecting joint.

[0014] In an optional embodiment of the present application, a scale plate is fixed to the second fixing plate to facilitate direct reading of the position coordinates of the detection section of the potential probe body in the pipeline to be tested.

[0015] In an optional embodiment of the present application, the threaded adjustment assembly also includes: a sliding guide tube, which is fixedly connected to the first fixed plate and is sleeved outside the potential probe body; a connecting bellows, one end of which is sealingly fixedly connected to the sliding guide tube, and the other end of which is fixedly connected to the guide frame; a probe cover, one end of which is fixedly connected to the adjustment screw; a second sealing ring, which can seal the gap between the potential probe body and the probe cover; a sealing plug, which can press and seal the gap between the second sealing ring and the potential probe body, and the sealing plug can be fixedly connected to the other end of the probe cover through an external thread to further seal the measuring mechanism to avoid leakage of liquid metal in the pipeline to be measured during the measurement process.

[0016] In an optional embodiment of the present application, the adjusting nut is adapted to be equipped with a driving hand wheel to facilitate manual adjustment of the position of the potential probe body.

[0017] In an optional embodiment of the present application, the potential probe body includes: a metal sleeve; a detection electrode, wherein two detection electrodes are arranged at intervals, and the two detection electrodes are insulated and inserted into the metal sleeve, the detection section extends to the outside of the metal sleeve, and the other end is equipped with a connecting electrode to ensure that the potential probe can accurately measure the potential difference of the local fluid of the liquid metal.

[0018] In a second aspect, the present invention provides a method for measuring the flow velocity distribution of liquid metal in a magnetic field, based on the above-mentioned liquid metal flow velocity distribution measuring mechanism in a magnetic field, comprising the following steps:

[0019] Sealingly connecting the connecting joint to the measuring interface corresponding to the pipeline to be measured, and installing the potential probe body in the connecting joint;

[0020] The detection section of the potential probe is adjusted to a preset initial position by means of a threaded adjustment assembly so that the detection section of the potential probe is parallel to and in the opposite direction of the flow direction of the liquid metal being measured;

[0021] Record the coordinates of each measuring point and the corresponding potential difference under the set external uniform magnetic field;

[0022] Calculate the liquid metal flow rate at each measuring point based on the conversion model;

[0023] Based on the liquid metal flow rate at each measuring point, the distribution trend of the liquid metal flow rate in the pipeline to be measured is obtained.

[0024] The method for measuring the flow velocity distribution of liquid metal in a magnetic field provided by the present invention is based on the above-mentioned liquid metal flow velocity distribution measuring mechanism in a magnetic field. The detection section of the potential probe is adjusted to a preset initial position through a threaded adjustment component so that the detection section of the potential probe is parallel and opposite to the flow direction of the liquid metal to be measured, and then the coordinates of each measuring point and the corresponding potential difference under the set external uniform magnetic field are recorded, and the liquid metal flow velocity of each measuring point is calculated based on the conversion model, and based on the liquid metal flow velocity of each measuring point, the liquid metal flow velocity distribution trend in the pipeline to be measured is obtained, thereby accurately measuring the flow velocity distribution data of the liquid metal.

[0025] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0026] 1. The liquid metal flow velocity distribution measurement mechanism in a magnetic field provided by the present invention comprises a connecting joint and a threaded adjustment assembly. The connecting joint can seal and movably insert a potential probe to prevent leakage of liquid metal in the measured pipeline during the measurement process. At the same time, the threaded adjustment assembly is fixedly connected to the connecting joint and can drive the potential probe to move axially along the connecting joint to accurately control the axial displacement of the potential probe through the threaded pair, thereby performing multiple measurements at different positions by continuously moving the potential probe to obtain flow velocity distribution data on a straight path from the wall of the measured pipeline to the central area. Therefore, the gap between the potential probe and the liquid metal flow pipeline can be sealed, and the displacement of the potential probe can be accurately controlled to accurately measure the flow velocity distribution data of the liquid metal, thereby meeting the needs of liquid metal MHD effect research.

[0027] 2. The method for measuring the flow velocity distribution of liquid metal in a magnetic field provided by the present invention is based on the above-mentioned mechanism for measuring the flow velocity distribution of liquid metal in a magnetic field. The detection section of the potential probe is adjusted to a preset initial position through a threaded adjustment component so that the detection section of the potential probe is parallel and opposite to the flow direction of the liquid metal to be measured. Then, the coordinates of each measuring point and the corresponding potential difference under the set external uniform magnetic field are recorded, and the liquid metal flow velocity of each measuring point is calculated based on the conversion model. Based on the liquid metal flow velocity of each measuring point, the flow velocity distribution trend of the liquid metal in the pipeline to be measured is obtained, thereby accurately measuring the flow velocity distribution data of the liquid metal. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0029] In the attached picture:

[0030] Figure 1 A schematic diagram of the structure of a liquid metal flow velocity distribution measurement mechanism in a magnetic field provided by an embodiment of the present invention;

[0031] Figure 2 A schematic cross-sectional view of a liquid metal flow velocity distribution measurement mechanism in a magnetic field provided by an embodiment of the present invention;

[0032] Figure 3 For the embodiment of the present invention Figure 2 A schematic diagram of the enlarged structure of part A;

[0033] Figure 4 For the embodiment of the present invention Figure 2 A schematic diagram of the enlarged structure of part B;

[0034] Figure 5 For the embodiment of the present invention Figure 2 Schematic diagram of the enlarged structure of part C;

[0035] Figure 6 For the embodiment of the present invention Figure 2 A schematic diagram of the enlarged structure of the D portion;

[0036] Figure 7 This is a liquid metal flow rate distribution trend diagram obtained in an embodiment of the present invention.

[0037] Marks and corresponding parts names in the attached drawings:

[0038] 100-connecting joint, 110-sealing cap, 120-first sealing ring, 200-threaded adjustment assembly, 210-mounting frame, 211-first fixed plate, 212-second fixed plate, 213-guide rod, 220-guide frame, 230-adjusting nut, 231-driving handwheel, 240-adjusting screw, 250-dial, 260-sliding guide tube, 270-connecting bellows, 280-sealing assembly, 281-second sealing ring, 282-probe cover, 283-sealing plug, 300-potential probe body, 310-metal cover, 320-detection electrode, 330-connecting electrode, 400-pipeline to be tested, 410-measuring interface, 500-potential acquisition equipment. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. The components of the embodiments of the present application described and shown in the drawings here can be arranged and designed in various different configurations.

[0040] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for which protection is sought, but merely represents selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

[0041] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0042] In the description of the present application, it should be noted that the indicated orientation or position relationship is based on the orientation or position relationship shown in the accompanying drawings, or is the orientation or position relationship in which the product of the application is usually placed when in use. It is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the present application.

[0043] It should be noted that in liquid metal MHD experiments, it is generally necessary to extract the liquid metal velocity distribution data at different positions on the path from the pipe wall to the center of the pipe, and a mechanism is needed to cooperate with the installation of the potential probe. The connection between the mechanism and the probe must be firm and the seal must be reliable to effectively prevent the leakage of liquid metal in the cladding channel and ensure the safety and stability of the experimental operation; it is also necessary to achieve precise adjustment of the probe measurement position after the mechanism is connected to the potential probe. At present, there is a lack of devices that meet the above requirements at the same time in the relevant field. Therefore, in order to meet the research needs of the liquid metal MHD effect and other related fields, it is necessary to develop a special mechanism for measuring the liquid metal velocity distribution in a strong magnetic environment in conjunction with the connection of a potential probe.

[0044] In order to solve the above-mentioned problems, the inventor innovatively designed the following technical solution, and the specific implementation solution of this application will be described in detail with reference to the accompanying drawings.

[0045] Example 1

[0046] Combination Figure 1 The present invention provides a liquid metal flow velocity distribution measurement mechanism in a magnetic field, comprising: a connecting joint 100, wherein the connecting joint 100 is used to connect a measurement interface 410 corresponding to a pipeline 400 to be measured, and the connecting joint 100 can be sealed and movably inserted with a potential probe; a threaded adjustment component 200, wherein the threaded adjustment component 200 is fixedly connected to the connecting joint 100, and the threaded adjustment component 200 is used to drive the potential probe to move along the axial direction of the connecting joint 100.

[0047] It should be understood that the present embodiment can be installed with a potential probe body 300, that is, the present embodiment also includes a potential probe body 300, the rod of the potential probe body 300 is movably inserted in the connecting joint 100, and the potential probe body 300 is transmission-connected to the threaded adjustment assembly 200, so that the liquid metal flow velocity distribution measurement mechanism in the magnetic field can directly measure the liquid metal flow velocity distribution in the magnetic field.

[0048] In this embodiment, the potential probe body 300 includes: a metal sleeve 310; a detection electrode 320, wherein two detection electrodes 320 are arranged at intervals, and the two detection electrodes 320 are insulated and inserted into the metal sleeve 310, the detection section extends to the outside of the metal sleeve 310, and the other end is adapted with a connecting electrode 330 to ensure that the potential probe can accurately measure the potential difference of the local fluid of the liquid metal.

[0049] That is, the potential probe body 300 mainly includes an external stainless steel tube, two internal potential probes, and an insulating material between the two. The two probe electrodes extending from the front end of the stainless steel tube are insulated except for the needle tip. The rear end connection electrode 330 of the potential probe body 300 is connected to the potential acquisition device 500 through a wire, and the potential acquisition device 500 can collect and record the potential difference (mV accuracy).

[0050] Combination Figure 2 and Figure 3 A sealing cap 110 is fixedly adapted inside the connecting joint 100, and the sealing cap 110 is sealed and connected to the connecting joint 100; the sealing cap 110 is sleeved outside the rod portion of the potential probe body 300, and the sealing cap 110 is adapted to be equipped with a first sealing ring 120, and the first sealing ring 120 is used to seal the gap between the sealing cap 110 and the rod portion of the potential probe body 300, so as to ensure that the connecting joint 100 can be sealed and the potential probe can be movably inserted.

[0051] Combination Figure 2 and Figure 4-Figure 6 The thread adjustment assembly 200 includes: a mounting frame 210, which is fixedly connected to the connecting joint 100; a guide frame 220, which is slidably connected to the mounting frame 210, the guide frame 220 can move along the axial direction of the connecting joint 100, and the guide frame 220 is fixedly connected to the potential probe body 300; an adjusting nut 230, the adjusting nut 230 is installed on the mounting frame 210, and the adjusting nut 230 can rotate along its own axis; an adjusting screw 240, the adjusting screw 240 is threadedly connected to the adjusting nut 230, the adjusting screw 240 is fixedly connected to the potential probe body 300, and the adjusting screw 240 is sleeved outside the potential probe body 300, so as to drive the guide frame 220 to move by rotating the adjusting nut 230, thereby accurately controlling the axial displacement of the potential probe through the threaded pair.

[0052] Specifically, the mounting frame 210 includes: a first fixing plate 211, which is fixedly connected to the connecting joint 100; a second fixing plate 212, which is used to install the adjusting nut 230; a guide rod 213, wherein a plurality of guide rods 213 are provided, and both ends of the guide rod 213 are respectively fixedly connected to the first fixing plate 211 and the second fixing plate 212, and the guide rod 213 is arranged in the guide frame 220 to ensure that the guide frame 220 can move smoothly along the axis of the connecting joint 100.

[0053] Typically, the second fixing plate 212 is provided with a scale plate 250 fixed thereto, so as to directly read out the position coordinates of the detection section of the potential probe body 300 in the pipeline 400 to be tested.

[0054] On this basis, the threaded adjustment assembly 200 also includes: a sliding guide tube 260, which is fixedly connected to the first fixed plate 211, and the sliding guide tube 260 is sleeved outside the potential probe body 300; a connecting bellows 270, one end of which is sealed and fixedly connected to the sliding guide tube 260, and the other end of which is fixedly connected to the guide frame 220; a probe cover 282, one end of which is fixedly connected to the adjustment screw 240; a second sealing ring 281, which can seal the gap between the potential probe body 300 and the probe cover 282; a sealing plug 283, which can compress and seal the gap between the second sealing ring 281 and the potential probe body 300, and the sealing plug 283 can be fixedly connected to the other end of the probe cover 282 through an external thread to further seal the measuring mechanism to avoid leakage of liquid metal in the measured pipeline 400 during the measurement process.

[0055] Generally, the adjusting nut 230 is adapted to be equipped with a driving hand wheel 231 to facilitate manual adjustment of the position of the potential probe body 300 .

[0056] Combination Figure 2-6 That is to say, the thread adjustment assembly 200 provided in this embodiment includes supporting components such as a sliding guide tube 260, a first fixing plate 211, a connecting bellows 270, a second fixing plate 212, a guide frame 220, and a linear guide rod 213; position adjustment components such as an adjustment screw 240, an adjustment nut 230, a dial 250, and a driving hand wheel 231; and sealing and fixing components such as a first sealing ring 120, a second sealing ring 281, a sealing cap 110, a sealing screw plug 283, and a probe cover 282. The center line of the potential probe body 300 is kept coincident with the center line of the main position adjustment components and the sealing and fixing components.

[0057] Among them, the first fixed plate 211 and the sliding guide tube 260 are welded in sequence; the bellows 270, the guide frame 220, the second fixed plate 212 and the main position adjustment component and the sealing fixed component (probe cover 282) are connected and fixed by snap-on bearings; and finally the first fixed plate 211, the guide frame 220 (with bearings added) and the second fixed plate 212 are connected and fixed through the guide rod 213.

[0058] At the same time, the adjusting screw 240 and the adjusting nut 230 are in contact through the ball bearings, and the rear of the adjusting nut 230 is connected to the fixed dial 250 and the driving handwheel 231 through screws. Based on the principle of screw transmission, after the adjustment components are assembled, the screw nut handwheel can be turned according to the reading of the dial 250, and the handwheel can be turned to adjust the screw 240 to move forward or backward.

[0059] It can be understood that in this embodiment, the sealing and fixing component adopts a double sealing and fixing method of the probe rear end (second sealing ring 281+probe cover 282+sealing plug 283) plus the probe front end (first sealing ring 120+sealing cap 110+connecting joint 100). The front and rear ends of the probe cover 282 are respectively connected to the connecting bellows 270 and the adjusting screw 240 in advance, the first sealing ring 120 and the second sealing ring 281 are made of fluororubber, and the sealing plug 283 and the sealing cap 110 are made of stainless steel.

[0060] It should be noted that the connection and fixing process of the potential probe body 300 is as follows:

[0061] The rear end of the potential probe body 300 is first inserted into the second sealing ring 281 to a suitable position, and then enters the interior of the mechanism through the interface until the second sealing ring 281 contacts the bottom of the groove at the front end of the probe cover 282;

[0062] After the sealing screw plug 283 is inserted into the potential probe body 300, it is connected to the probe cover 282 through threads and is tightened until it is pressed tightly against the second sealing ring 281 together with the probe cover 282;

[0063] The sealing cap 110 is finally inserted into the potential probe body 300 , and the front end of the potential probe body 300 is squeezed and fixed by a rubber ring (first sealing ring 120 ) inside the sealing cap 110 , and the outside of the sealing cap 110 is connected to the joint 100 by a threaded connection.

[0064] In summary, the liquid metal flow velocity distribution measurement mechanism in a magnetic field provided in this embodiment includes a connecting joint 100, a threaded adjustment assembly 200, a potential probe body 300 and a potential acquisition device 500; the connecting joint 100 can seal and movably insert the potential probe to prevent leakage of liquid metal in the measured pipeline 400 during the measurement process; the threaded adjustment assembly 200 is fixedly connected to the connecting joint 100, and can drive the potential probe to move axially along the connecting joint 100; the potential probe body 300 and the potential acquisition device 500 are electrically connected.

[0065] When in use, the connecting joint 100 corresponding to the precise displacement mechanism is welded and installed at the position of the flow velocity to be measured (y direction) of the liquid metal pipeline, and then the potential probe body 300 is installed into the threaded adjustment assembly 200, and the fixing and sealing are checked to ensure that the fixing and sealing are correct. At the same time, the connecting joint 100 and the interface of the pipeline 400 to be measured are fixed through the flange to ensure that the sealing is correct; then the two wires of the potential probe body 300 are led out from the inside of the adjustment screw 240 and connected to the potential collection device 500, and then the driving hand wheel 231 is rotated to make the detection electrode 320 at the front end of the potential probe body 300 enter the predetermined position inside the pipeline 400 to be measured. After the MHD experiment starts, the liquid metal circulates, and firstly a uniform magnetic field B0 is applied in the z direction, and the driving hand wheel 231 is adjusted to make the two detection electrodes 320 (spacing d1) at the front end of the potential probe body 300 to the predetermined position (x, total length 2L), and the potential difference data of each position point is collected and recorded. After the experiment, according to the formula The flow velocity uy of each point on the x-direction path inside the pipeline 400 to be tested is calculated and a distribution change trend is formed.

[0066] Thus, the liquid metal flowing in the pipeline 400 to be tested under a strong magnetic environment cuts the magnetic flux lines, generating an induced electromotive force, and the potential difference of the local fluid can be collected by the potential probe body 300 and recorded by the potential collection device 500, and the local flow velocity can be obtained by conversion. At the same time, after the potential probe is connected, the measuring position of the probe in the fluid is accurately adjusted by the driving hand wheel 231 component of the mechanism. By continuously moving the potential probe to perform multiple measurements at different positions, the flow velocity distribution data on the straight path from the wall of the pipeline 400 to the center area can be obtained.

[0067] In summary, the liquid metal flow velocity distribution measurement mechanism in a magnetic field provided in this embodiment can seal the gap between the potential probe and the liquid metal flow pipe, and can accurately control the displacement of the potential probe to accurately measure the flow velocity distribution data of the liquid metal, thereby meeting the needs of liquid metal MHD effect research.

[0068] Among them, this embodiment adjusts the probe position through the screw nut, the potential probe can move forward and backward stably and can accurately locate the flow velocity distribution measurement point; and there is no need for welding between the mechanism and the pipeline 400 to be measured and the potential probe, and adopts a multiple connection sealing and fixing method of flange connection, probe front end sealing (sealing ring + sealing cap 110 + interface) and probe rear end sealing (probe cover 282 + sealing ring + sealing screw plug 283), which can simultaneously ensure the connection between the mechanism and the pipeline 400 to be measured, and the mechanism and the potential probe. The connection is firm and safely sealed, and liquid metal leakage is effectively prevented; at the same time, the sealing and fixing parts of the mechanism are disassembled and the overall structure is simple and light, so the potential probe can be replaced conveniently and quickly, or the potential probe and the pipeline 400 to be measured can be partially modified to meet different measurement requirements.

[0069] Example 2

[0070] This embodiment provides a method for measuring the flow velocity distribution of liquid metal in a magnetic field, based on the mechanism for measuring the flow velocity distribution of liquid metal in a magnetic field described in Embodiment 1, comprising the following steps:

[0071] S10 , sealingly connecting the connection joint 100 to the measuring interface 410 corresponding to the pipeline 400 to be measured, and installing the potential probe body 300 in the connection joint 100 .

[0072] Specifically, after selecting the pipeline 400 to be tested and the flow velocity measurement path inside the pipeline (total length 2L), the connection joint 100 of the liquid metal flow velocity distribution measurement mechanism in the magnetic field is modified accordingly as needed. In this embodiment, the connection joint 100 is a boss flange structure, and the pipeline 400 to be tested has a hole opened at the corresponding connection position and a groove flange is welded (a polytetrafluoroethylene sealing gasket is placed inside the groove).

[0073] The rear end of the potential probe body 300 is first inserted into the second sealing ring 281 to a suitable position, and then enters the interior of the mechanism through the interface until the second sealing ring 281 contacts the bottom of the groove at the front end of the probe cover 282; the sealing screw plug 283 is inserted into the potential probe body 300 and connected to the probe cover 282 through a thread, and is tightened until the second sealing ring 281 is pressed tightly together with the probe cover 282; the sealing cap 110 is finally inserted into the potential probe body 300, and the front end of the potential probe body 300 is squeezed and fixed by a rubber ring (first sealing ring 120) inside the sealing cap 110, and the outside of the sealing cap 110 is connected to the joint 100 through a thread.

[0074] S20, adjusting the detection section of the potential probe to a preset initial position through the threaded adjustment assembly 200, so that the detection section of the potential probe is parallel to and opposite to the flow direction of the liquid metal to be measured.

[0075] Specifically, the adjusting thread adjusting assembly 200 moves the detection electrode 320 of the potential probe body 300 to a predetermined initial position, and ensures that the needle of the detection electrode 320 is reversed (-y) and parallel to the flow direction (y) of the liquid metal. Then, the connecting joint 100 is connected by a flange, and the fixed seal is confirmed to be correct. At the same time, after the connection electrode 330 of the potential probe body 300 is connected to the two wires, it is led out from the inside of the adjusting screw 240 and connected to the potential collection device 500.

[0076] S30, recording the coordinates of each measuring point and the corresponding potential difference under the set external uniform magnetic field.

[0077] Specifically, after the experiment started, Figure 1 The liquid metal in the test pipe 400 shown flows along the y direction, and an external uniform magnetic field B0 is applied in the z direction; the inner wall point at the measuring interface 410 of the test pipe 400 is (L, 0, 0), the corresponding pipe center point in the x direction is (0, 0, 0), and a point on the inner wall of the pipe is (-L, 0, 0). Then record the set external uniform magnetic field B0 value, and adjust the driving hand wheel 231 to make the detection electrode 320 (spacing d1) move forward and backward along the x direction, that is, from (L, 0, 0) to (-L, 0, 0) and record the coordinates of each measurement point (x, 0, 0) and the corresponding potential difference value

[0078] S40, calculating the liquid metal flow rate at each measuring point based on the conversion model.

[0079] That is, according to the conversion model The flow velocity uy at each point (x,0,0) is calculated and converted.

[0080] S50 , based on the liquid metal flow rate at each measuring point, obtaining the distribution trend of the liquid metal flow rate in the pipeline 400 to be measured.

[0081] Combination Figure 3 The final result is the liquid metal velocity distribution trend diagram on the path from (L, 0, 0) to (-L, 0, 0) inside the pipeline in the x direction.

[0082] That is to say, the method for measuring the flow velocity distribution of liquid metal in a magnetic field provided in this embodiment is based on the above-mentioned liquid metal flow velocity distribution measuring mechanism in a magnetic field, and the detection section of the potential probe is adjusted to a preset initial position through the threaded adjustment component 200, so that the detection section of the potential probe is parallel and opposite to the flow direction of the liquid metal to be measured, and then the coordinates of each measuring point and the corresponding potential difference under the set external uniform magnetic field are recorded, and the liquid metal flow velocity of each measuring point is calculated based on the conversion model, and based on the liquid metal flow velocity of each measuring point, the liquid metal flow velocity distribution trend in the measured pipeline 400 is obtained, thereby accurately measuring the flow velocity distribution data of the liquid metal.

[0083] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A liquid metal flow velocity distribution measuring mechanism in a magnetic field, characterized in that: include: A connecting joint (100), the connecting joint (100) being used to connect to a measuring interface (410) corresponding to the pipeline (400) to be measured, and the connecting joint (100) being capable of sealing and movably inserting a potential probe; A threaded adjustment component (200), the threaded adjustment component (200) is fixedly connected to the connecting joint (100), and the threaded adjustment component (200) is used to drive the potential probe to move along the axial direction of the connecting joint (100).

2. The liquid metal flow velocity distribution measuring mechanism in a magnetic field according to claim 1, characterized in that: It also comprises a potential probe body (300), the rod portion of the potential probe body (300) is movably inserted in the connecting joint (100), and the potential probe body (300) is drivingly connected to the threaded adjustment assembly (200).

3. The liquid metal flow velocity distribution measuring mechanism in a magnetic field according to claim 2, characterized in that: A sealing cap (110) is fixedly adapted inside the connection joint (100), and the sealing cap (110) is sealedly connected to the connection joint (100); The sealing cap (110) is sleeved outside the rod portion of the potential probe body (300), and the sealing cap (110) is adapted to be equipped with a first sealing ring (120), wherein the first sealing ring (120) is used to seal the gap between the sealing cap (110) and the rod portion of the potential probe body (300).

4. The liquid metal flow velocity distribution measuring mechanism in a magnetic field according to claim 2, characterized in that: The thread adjustment assembly (200) comprises: A mounting frame (210), the mounting frame (210) being fixedly connected to the connecting joint (100); A guide frame (220), the guide frame (220) is slidably connected to the mounting frame (210), the guide frame (220) is movable along the axial direction of the connecting joint (100), and the guide frame (220) is fixedly connected to the potential probe body (300); an adjusting nut (230), the adjusting nut (230) being mounted on the mounting frame (210), and the adjusting nut (230) being capable of rotating along its own axis; An adjusting screw (240), wherein the adjusting screw (240) is threadedly connected to the adjusting nut (230), the adjusting screw (240) is fixedly connected to the potential probe body (300), and the adjusting screw (240) is sleeved outside the potential probe body (300).

5. The liquid metal flow velocity distribution measuring mechanism in a magnetic field according to claim 4, characterized in that: The mounting frame (210) comprises: A first fixing plate (211), the first fixing plate (211) being fixedly connected to the connecting joint (100); a second fixing plate (212), wherein the second fixing plate (212) is used for mounting the adjusting nut (230); A guide rod (213), wherein a plurality of guide rods (213) are provided, and two ends of the guide rod (213) are respectively fixedly connected to the first fixing plate (211) and the second fixing plate (212), and the guide rod (213) is disposed in the guide frame (220).

6. The liquid metal flow velocity distribution measuring mechanism in a magnetic field according to claim 5, characterized in that: The second fixing plate (212) is provided with a scale plate (250) fixed thereto.

7. The liquid metal flow velocity distribution measuring mechanism in a magnetic field according to claim 5, characterized in that: The thread adjustment assembly (200) further comprises: A sliding conduit (260), wherein the sliding conduit (260) is fixedly connected to the first fixing plate (211), and the sliding conduit (260) is sleeved outside the potential probe body (300); A connecting bellows (270), one end of the connecting bellows (270) being sealed and fixedly connected to the sliding guide tube (260), and the other end of the connecting bellows (270) being fixedly connected to the guide frame (220); A probe cover (282), one end of which is fixedly connected to the adjusting screw (240); A second sealing ring (281), wherein the second sealing ring (281) is capable of sealing the gap between the potential probe body (300) and the probe cover (282). A sealing screw plug (283) can be pressed and sealed to seal the gap between the second sealing ring (281) and the potential probe body (300), and the sealing screw plug (283) can be fixedly connected to the other end of the probe sleeve (282) through an external thread.

8. The liquid metal flow velocity distribution measuring mechanism in a magnetic field according to claim 4, characterized in that: The adjusting nut (230) is adapted to be equipped with a driving hand wheel (231).

9. The liquid metal flow velocity distribution measuring mechanism in a magnetic field according to any one of claims 2 to 8, characterized in that: The potential probe body (300) comprises: Metal sleeve (310); Detection electrodes (320), two of which are arranged at intervals, the two detection electrodes (320) are both insulated and inserted into the metal sleeve (310), the detection section extends outside the metal sleeve (310), and the other end is adapted with a connection electrode.

10. A method for measuring the flow velocity distribution of liquid metal in a magnetic field, characterized in that: The liquid metal flow velocity distribution measuring mechanism in a magnetic field according to any one of claims 1 to 9 comprises the following steps: The connection joint (100) is sealedly connected to a measuring interface (410) corresponding to the pipeline (400) to be measured, and the potential probe body (300) is installed in the connection joint (100); The detection section of the potential probe is adjusted to a preset initial position by means of a threaded adjustment component (200) so that the detection section of the potential probe is parallel to and in the opposite direction of the flow direction of the liquid metal being measured; Record the coordinates of each measuring point and the corresponding potential difference under the set external uniform magnetic field; Calculate the liquid metal flow rate at each measuring point based on the conversion model; Based on the liquid metal flow rate at each measuring point, the distribution trend of the liquid metal flow rate in the pipeline (400) to be measured is obtained.

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