Magnetic Levitation Gas-Solid Two-Phase Shock Tube Experimental Device and Experimental Method

Abstract

The present invention discloses a magnetic levitation gas-solid two-phase shock tube experimental device and an experimental method. A groove is provided in the visualization test section, and a partition plate is installed in the groove. The partition plate rotates and drops to the vertical position to block the flow. After the two partition plates drop, a closed space for placing particles is formed; there are detachable electromagnetic coils above and below the visualization test section. When the electromagnetic coils are energized, an electromagnetic field is generated, so that the particles form a static suspension particle bed under the balance of magnetic force and gravity; a pressure sensor is provided on the square tube section; after the shock wave passes through the visualization test section and impacts the suspension particle bed, images are recorded, and pressure data is collected to obtain the attenuation change of the shock wave Mach number, thereby completing the gas-solid two-phase shock tube experiment. The present invention uses a magnetic levitation component to make the particles form a static suspension particle bed, conducts experimental research on gas-solid two-phase flow without being interfered by external conditions, increases the smoothness and airtightness of the inner wall surface of the shock tube, improves the experimental accuracy and facilitates the experimental operation.

Description

Technical Field

[0001] The present invention relates to a shock tube experimental device, and in particular to a gas-solid two-phase shock tube experimental device and experimental method with more accurate experimental results after improvement. Background Art

[0002] The interaction between shock waves and particle swarms is a common and important phenomenon in compressible particle-laden flows, involving many fields such as aerospace, medical and health, safety prevention and control, and environmental protection. Specific applications include, for example, the explosion of solid-particle-containing explosives, the propulsion of solid fuels in rocket engines, high-speed flight in dusty atmospheres, needle-free injection of drug powders, supersonic cold spraying, dry powder fire extinguishing, dust explosions, volcanic eruptions, etc. To carry out research on the complex gas-solid two-phase flow problems when shock waves interact with dense particle swarms, the key lies in the accurate control of the shock Mach number and the initial spatial distribution of particles before the incident shock wave interacts with the dense particle swarm, as well as the acquisition of dynamic image data of shock waves, contact surfaces, and particle swarms afterwards.

[0003] Because in the current experimental device, particles fall under the action of gravity to form a particle bed in the shock tube. The falling of particles under the action of gravity will cause the particle bed to be unevenly distributed, which has a certain impact on the experimental accuracy; moreover, the particle release device affects the smoothness of the inner wall of the shock tube, resulting in poor airtightness when the gas passes through the visualization test section, and the gas will leak when passing through the particle bed; the current experimental device can only form a particle curtain with a very small width, reducing the operability of the experiment. The existing experimental devices need to address certain problems and defects regarding the above issues. Summary of the Invention

[0004] Aiming at the problems existing in the above background art, the purpose of the present invention is to provide a magnetically levitated gas-solid two-phase shock tube experimental device and experimental method, which can well solve the problems of the smoothness and airtightness of the inner wall of the shock tube, and can better make the particle bed present a static distribution state, facilitating subsequent measurements.

[0005] The technical solution adopted by the present invention to solve its technical problems is as follows:

[0006] I. A magnetically levitated gas-solid two-phase shock tube experimental device:

[0007] It includes a high-pressure section, a bursting diaphragm, a pneumatic section, a circular-to-square transition section, a first square pipe section, a visualization test section, a second square pipe section, and a collection box; the outlet end of the high-pressure gas cylinder is sequentially connected to the inlet section of the first square pipe section after passing through the high-pressure section and the pneumatic section, and the pneumatic section and the first square pipe section are connected through the circular-to-square transition section. There is a bursting diaphragm between the ports of the high-pressure section and the pneumatic section. The outlet end of the first square pipe section is sequentially connected to the collection box after passing through the visualization test section and the second square pipe section; on both sides of the inner top surface and the inner bottom surface of the visualization test section, grooves are provided. In each groove, a partition board is hingedly installed through a partition board fixing nut and a partition board connecting rod. The partition board connecting rod penetrates through the partition board and is fixedly connected. Both ends of the partition board connecting rod are movably installed on the side wall of the visualization test section and a partition board fixing nut is installed at the end for limiting; the partition board connecting rod serves as the rotation axis of the partition board, and the rotation axis of the partition board is located on the side close to the center of the visualization test section; the two partition boards on both sides of the inner top surface of the visualization test section are symmetrically arranged with respect to the center of the visualization test section, and the two partition boards on both sides of the inner bottom surface of the visualization test section are symmetrically arranged with respect to the center of the visualization test section; the end of the partition board connecting rod is connected to an external rotation drive source, which drives the partition board connecting rod to rotate, thereby driving the partition board to rotate and fall to the vertical position to block the flow of the visualization test section. Then, after the two partition boards fall, an internal closed space of the visualization test section is formed, and there are particles in the closed space; a detachable electromagnetic coil is installed above and below the outside of the visualization test section. The axial directions of the two detachable electromagnetic coils are coaxially arranged vertically and are symmetrically arranged above and below the visualization test section; both detachable electromagnetic coils are connected to an adjustable DC power supply. The detachable electromagnetic coils are driven by the adjustable DC power supply to generate an electromagnetic field, and the electromagnetic field exerts an anti-gravity force vertically upward on the particles. By adjusting the magnitude of the current passing through the detachable electromagnetic coils, the particles in the internal closed space surrounded by the partition boards form a static suspension particle bed under the balance of the magnetic force and the gravity; a first pressure sensor and a second pressure sensor are installed on the first square pipe section at intervals along the bursting direction, and a third pressure sensor and a fourth pressure sensor are installed on the second square pipe section at intervals along the bursting direction.

[0008] The length dimensions of the two partition boards on both sides of the inner top surface of the visualization test section are the upper and lower inner diameter dimensions of the visualization test section plus the thickness dimension of the groove.

[0009] The length dimensions of the two partition boards on both sides of the inner bottom surface of the visualization test section are the upper and lower inner diameter dimensions of the visualization test section plus the thickness dimensions of the two grooves.

[0010] The rotation axes of the two partition plates on both sides of the top surface inside the visual test section are closer to the center of the visual test section than the rotation axes of the two partition plates on both sides of the bottom surface inside the visual test section, forming a staggered distribution of the upper and lower groups of partition plates; the distance between the two partition plates on both sides of the top surface inside the visual test section is d, and the distance between the two partition plates on both sides of the bottom surface inside the visual test section is 3d.

[0011] By adjusting the current intensity of the electromagnetic coil, the control of the particle suspension and the particle volume fraction in the internal enclosed space surrounded by the partition plates is achieved.

[0012] By adjusting the two partition plates in different combinations to fall to form internal enclosed spaces of different sizes and positions, the control of particle suspension and particle volume fraction in the gas-solid two-phase shock tube experiment is realized.

[0013] The visual test section described above is made of a transparent material.

[0014] The coil winding of the electromagnetic coil described above meets the following setting requirements:

[0015]

[0016] Among them, z(n) represents the position of the coil along the Z direction corresponding to the number of coil windings per meter being n, and the z direction is the vertical direction; v is the volume size of a single particle, μ 0 is the vacuum magnetic permeability of the particle, M ∞ is the saturation magnetization intensity of the material of the particle, n is the number of coil windings per meter, n 0 represents the number of coil windings at the initial position when the z direction is zero, I is the current magnitude of the coil, γ characterizes the magnetic induction characteristics of the particle, and c is a constant.

[0017] II. An experimental method for the magnetic suspension gas-solid two-phase shock tube experimental device:

[0018] Using the above device, with the initial high-pressure gas cylinder not opened, drive the two partition plates to rotate and fall to the vertical position through the partition connecting rod, place the particles with the weight measured and recorded well in the internal enclosed space surrounded by the two partition plates, and use vibration to make the particles evenly distributed in the internal enclosed space;

[0019] Then turn on the adjustable DC power supply to make the electromagnetic coil energized to generate an electromagnetic field, adjust the current of the electromagnetic coil to make the particles in the internal enclosed space suspended and form a static suspended particle bed with uniform distribution, and collect the video images of the particle bed in the visual test section through a high-speed camera;

[0020] Then, open the high-pressure gas cylinder to create a pressure ratio between the high-pressure section and the pressure section. Generate a shock wave by bursting a diaphragm. The shock wave passes through the pressure section, the circular-to-square transition section, and the first square pipe section in sequence and then enters the visualization test section. After the shock wave impacts and collides with the static suspended particle bed in the visualization test section, it enters the collection box through the second square pipe section;

[0021] When the shock wave impacts and collides with the static suspended particle bed in the visualization test section, use a schlieren system to reflect the shock-wave-particle interaction and particle-particle interaction generated by the shock wave and particle collision at the visualization test section into an image. At the same time, record the image with a high-speed camera, and collect pressure data through four pressure sensors to obtain the attenuation change of the shock wave Mach number, thus completing the gas-solid two-phase shock tube experiment.

[0022] The attenuation change of the shock wave is obtained by collecting pressure data through four pressure sensors and processing it in the following specific way:

[0023] 1) Calculate the velocity V of the shock wave according to the axial distance between the first pressure sensor and the second pressure sensor and the time difference of the pressure data collected by the first pressure sensor and the second pressure sensor respectively using the following formula S :

[0024]

[0025] In the formula, d represents the axial distance between the first pressure sensor and the second pressure sensor, and t 0 、t 1 represent the moments when the shock wave passes through the first pressure sensor and the second pressure sensor respectively;

[0026] Furthermore, calculate the Mach number M S of the incident shock wave:

[0027]

[0028] where a 0 is the local speed of sound;

[0029] 2) Calculate the Mach number of the shock wave in the same way as in step 1) using the pressure data collected by the third pressure sensor and the fourth pressure sensor;

[0030] 3) Take the difference between the Mach number of the shock wave obtained in step 2) and the Mach number of the incident shock wave obtained in step 1) as the attenuation change of the shock wave Mach number.

[0031] Through the improvement of the previous experimental device, the present invention uses a magnetic levitation component to form a static suspension particle bed of particles, conducts experimental research on gas-solid two-phase flow without being interfered by external conditions, increases the smoothness and airtightness of the inner wall surface of the shock tube, improves the experimental accuracy and facilitates the experimental operation.

[0032] The beneficial effects of the present invention are as follows:

[0033] The present invention can make the particles statically suspended in the shock tube uniformly and without being affected by other external conditions such as gravity. Moreover, the airtightness and smoothness of the inner wall of the shock tube have been greatly improved compared with the previous experimental device, providing better experimental technical realization for subsequent experiments such as high-speed schlieren photography of the particle bed when a shock wave interacts with a dense particle bed using a high-speed camera and a schlieren apparatus, and observing and analyzing behaviors and laws such as shock wave reflection and transmission, and changes in the thickness of the particle bed.

[0034] In the prior art, the two-phase shock tube experiment can only be achieved by releasing particles, resulting in leakage, non-smooth particle movement, and an inaccurate dynamic experiment achieved by acceleration. The present invention can more uniformly and realistically achieve the goal of the two-phase shock tube experiment, realize the process of blasting particles in a static two-phase shock tube, and solve the technical problem of inaccurate experimental results in the existing two-phase shock tube experiment. Description of the Drawings

[0035] Figure 1 is a schematic diagram of the overall structure of the present invention.

[0036] Figure 2 is a working schematic diagram with the distance between the partition plates being d.

[0037] Figure 3 is a vertical state diagram with the distance between the partition plates being 2d.

[0038] Figure 4 is for Figure 3 the lower half cross-sectional view of

[0039] Figure 5 is a particle volume fraction diagram along the shock wave propagation direction.

[0040] In the figure: 1. High-pressure gas cylinder, 2. High-pressure section, 3. Blasting diaphragm, 4. Air pressure section, 5. Round-to-square transition section, 6. First square pipe section, 7. Visualization test section, 8. Electromagnetic coil, 9. Adjustable DC power supply, 10. Collection box, 11. Partition plate, 12. Second square pipe section, 13. Collection box, 14. Fourth pressure sensor, 15. Third pressure sensor, 16. Second pressure sensor, 17. First pressure sensor, 18. Partition plate fixing nut, 19. Partition plate connecting rod, 20. Inner wall of the visualization test section. Detailed Implementation Manner

[0041] The present invention will be further described below in conjunction with the accompanying drawings and examples.

[0042] As Figure 1 shown, the specific implementation includes a high-pressure section 2, a blasting diaphragm 3, a pressure section 4, a circular-to-square transition section 5, a first square pipe section 6, a visualization test section 7, a second square pipe section 12, and a collection box 13; the outlet end of the high-pressure gas cylinder 1 is sequentially connected to the inlet section of the first square pipe section 6 after passing through the high-pressure section 2 and the pressure section 4, and the pressure section 4 and the first square pipe section 6 are connected through the circular-to-square transition section 5. There is a blasting diaphragm 3 between the ports of the high-pressure section 2 and the pressure section 4. The outlet end of the first square pipe section 6 passes through the visualization test section 7 and the second square pipe section 12 in sequence and then is connected to the collection box 13; open the high-pressure gas cylinder 1 to make there be a pressure ratio between the high-pressure section 2 and the pressure section 4, and generate a shock wave through the blasting of the blasting diaphragm 3. The shock wave passes through the pressure section 4, the circular-to-square transition section 5, the first square pipe section 6, the visualization test section 7, and the second square pipe section 12 in sequence and then enters the collection box 13.

[0043] As Figure 2 、 Figure 3 shown, grooves are opened on both sides of the inner top surface and the inner bottom surface of the visualization test section 7. In each groove, a partition plate 11 is hingedly installed through a partition plate fixing nut 18 and a partition plate connecting rod 19. As Figure 4 shown, the partition plate connecting rod 19 penetrates through and is fixedly connected to the partition plate 11. Both ends of the partition plate connecting rod 19 are movably installed on the side wall of the visualization test section 7, and a partition plate fixing nut 18 is installed at the end part passing through the side wall for limiting; the part of the partition plate connecting rod 19 outside the shock wave pipe wall has threads, and after reaching the vertical position, the partition plate 11 is fixed by using the partition plate fixing nut 18. The partition plate connecting rod 19 serves as the rotation axis of the partition plate 11, and the rotation axis of the partition plate 11 is located on the side close to the center of the visualization test section 7, that is, the partition plate connecting rod 19 is arranged on the side of the partition plate 11 close to the center of the visualization test section 7; the two partition plates 11 on both sides of the inner top surface of the visualization test section 7 are symmetrically arranged with respect to the center of the visualization test section 7, and the two partition plates 11 on both sides of the inner bottom surface of the visualization test section 7 are symmetrically arranged with respect to the center of the visualization test section 7; the end part of the partition plate connecting rod 19 is connected to an external rotation driving source, and the partition plate connecting rod 19 is driven to rotate, thereby driving the partition plate 11 to rotate and fall to the vertical position to block the flow of the visualization test section 7, that is, in a state perpendicular to the wall surface. Then, after the two partition plates 11 fall, an internal closed space of the visualization test section 7 is formed, and there are particles in the closed space.

[0044] A detachable electromagnetic coil 8 is installed above and below the outside of the visualization test section 7. The two detachable electromagnetic coils 8 are arranged coaxially and vertically in the axial direction, and are symmetrically arranged above and below the visualization test section 7; both detachable electromagnetic coils 8 are connected to an adjustable DC power supply 9. By driving the detachable electromagnetic coil 8 to energize and generate an electromagnetic field through the adjustable DC power supply 9, the electromagnetic field exerts an anti-gravity force vertically upward on the particles, enabling the particles to form a suspended particle bed in space. By adjusting the magnitude of the current passing through the detachable electromagnetic coil 8, the particles in the internal enclosed space surrounded by the partition plate 11 form a static suspended particle bed under the balance of magnetic force and gravity, and the particle bed is not disturbed by external conditions; a first pressure sensor 17 and a second pressure sensor 16 are arranged at intervals along the blasting direction on the first square pipe section 6, and a third pressure sensor 15 and a fourth pressure sensor 14 are arranged at intervals along the blasting direction on the second square pipe section 12.

[0045] The length dimensions of the two partition plates 11 on both sides of the inner top surface of the visualization test section 7 are the inner diameter dimensions of the upper and lower parts of the visualization test section 7 plus the thickness dimension of the groove, so that when the partition plate 11 rotates to the vertical position, it can completely cover the inner diameter dimension of the visualization test section 7 and block the flow of the visualization test section 7.

[0046] The length dimensions of the two partition plates 11 on both sides of the inner bottom surface of the visualization test section 7 are the inner diameter dimensions of the upper and lower parts of the visualization test section 7 plus the thickness dimensions of the two grooves, so that when the partition plate 11 rotates to the vertical position, it can completely cover the inner diameter dimension of the visualization test section 7 and block the flow of the visualization test section 7.

[0047] The rotation axes of the two partition plates 11 on both sides of the inner top surface of the visualization test section 7 are closer to the center of the visualization test section 7 than the rotation axes of the two partition plates 11 on both sides of the inner bottom surface of the visualization test section 7, forming a staggered distribution of the upper and lower groups of partition plates 11; the distance between the two partition plates 11 on both sides of the inner top surface of the visualization test section 7 is d, and the distance between the two partition plates 11 on both sides of the inner bottom surface of the visualization test section 7 is 3d. Under the above structure, the internal enclosed spaces with widths of d, 2d, and 3d along the blasting direction can be formed by different combinations of two partition plates 11.

[0048] In specific implementation, since it is extremely difficult for the cuboid partition plate to rotate, the two ends of the partition plate should be processed into semi-cylindrical shapes. In order to reduce the influence of the cylindrical shape of the partition plate on the smoothness of the inner wall surface of the shock tube, the thickness of the partition plate should be as small as possible.

[0049] By adjusting the current intensity of the electromagnetic coil 8, the control of the particle suspension and the particle volume fraction in the internal enclosed space surrounded by the partition plate 11 is realized, and the total number of particles remains fixed.

[0050] By adjusting the internal enclosed spaces of different sizes and positions formed by the falling of two partition plates 11 in different combinations, the suspension of particles and the regulation of the particle volume fraction in the gas-solid two-phase shock tube experiment are realized, and the total number of particles remains fixed.

[0051] The visualization test section 7 is made of a transparent material. The visualization test section is of a cuboid structure. Compared with the cylindrical structure, the influence of light refraction, focusing, etc. is minimized, making the images collected by the schlieren instrument clearer. The particle material is a magnetic material.

[0052] A high-speed camera is arranged on the side of the visualization test section 7. The high-speed camera is connected to a computer to directly photograph the visualization test section. The high-speed schlieren technique is adopted, and the high-speed camera and the computer are combined to observe and record the action of the shock wave on the dense particle group.

[0053] In specific implementation, the coil winding of the electromagnetic coil 8 meets the following set requirements:

[0054]

[0055] Among them, z(n) represents the position of the coil along the Z direction corresponding to the number of coil windings per meter being n. The z direction is the vertical direction; v is the volume size of a single particle, and μ 0 is the vacuum magnetic permeability of the particle, M ∞ is the saturation magnetization intensity of the material of the particle, n is the number of coil windings per meter, and n 0 represents the number of coil windings at the initial position when the z direction is zero. I is the current magnitude of the coil, γ characterizes the magnetic induction characteristics of the particle, and c is a constant.

[0056] In specific implementation, the lower end of the lower electromagnetic coil 8 is set as the position where the z direction is zero.

[0057] In the specific implementation of the present invention, when operating with partition plates with different distances d, 2d, 3d representing the width between the partition plates and bursting diaphragms of different thicknesses, the schlieren instrument is used to obtain the images of the interaction between the shock wave and the dense particle bed, and the high-speed camera is used to record the schematic diagrams of the interaction between the shock wave and the particle bed in each state; the shock wave passes through the particle bed and continues to move forward, passes through the third and fourth pressure sensors, obtains another set of Mach numbers, and finally reaches the collection box; then the attenuation change of the shock wave Mach number is obtained through the data of the front and rear pressure sensors.

[0058] The experimental process of the present invention is as follows:

[0059] Using the above device, with the initial high-pressure gas cylinder 1 not opened, the two partition plates 11 are driven by the partition plate connecting rod 19 to rotate and fall to the vertical position, and the particles with the weight measured and recorded are placed in the internal enclosed space surrounded by the two partition plates 11, and vibration is used to make the particles evenly distributed in the internal enclosed space;

[0060] Then turn on the adjustable DC power supply 9 to energize the electromagnetic coil 8 to generate an electromagnetic field, and adjust the current of the electromagnetic coil 8 to suspend the particles in the internal closed space and form a static suspension particle bed with uniform distribution. The video image of the particle bed in the acquisition visualization test section 7 is transmitted through a high-speed camera;

[0061] Use the rotation drive source to drive the partition connecting rod 19 to restore the two partition plates 11 to the horizontal position. Then open the high-pressure gas cylinder 1 to make the high-pressure section 2 and the pressure section 4 have a pressure ratio, and generate a shock wave by bursting the diaphragm 3. The shock wave passes through the pressure section 4, the circular-to-square transition section 5, and the first square pipe section 6 in sequence and then enters the visualization test section 7. After the shock wave passes through the visualization test section 7 and impacts the static suspension particle bed, it enters the collection box 13 through the second square pipe section 12;

[0062] When the shock wave passes through the visualization test section 7 and impacts the static suspension particle bed, use a schlieren instrument to reflect the shock wave-particle interaction and particle-particle interaction generated by the shock wave and particle collision at the visualization test section 7 into an image. At the same time, use a high-speed camera to record the image, and collect pressure data through four pressure sensors 14-17 to obtain the attenuation change of the shock wave Mach number.

[0063] The specific method for obtaining the attenuation change of the shock wave by collecting pressure data through four pressure sensors 14-17 is as follows:

[0064] 1) Calculate the velocity V of the shock wave according to the axial distance between the first pressure sensor 17 and the second pressure sensor 16 and the time difference of the pressure data collected by the first pressure sensor 17 and the second pressure sensor 16 respectively using the following formula S :

[0065]

[0066] In the formula, d represents the axial distance between the first pressure sensor 17 and the second pressure sensor 16, and t 0 , t 1 respectively represent the moments when the shock wave passes through the first pressure sensor 17 and the second pressure sensor 16;

[0067] Furthermore, calculate the Mach number M of the incident shock wave S :

[0068]

[0069] Among them, a 0 is the local sound speed;

[0070] 2) The pressure data collected by the third pressure sensor 15 and the fourth pressure sensor 14 is used to calculate the Mach number of the shock wave in the same way as in step 1).

[0071] 3) The difference obtained by subtracting the Mach number of the shock wave obtained in step 2) from the Mach number of the incident shock wave obtained in step 1) is used as the decay change of the shock wave Mach number.

[0072] In specific implementation, plane incident shock waves with different Mach numbers are generated by using nickel alloy bursting diaphragms with cross-notch and different thicknesses to avoid fragmented bursting of the diaphragms.

[0073] The relationship between the particle volume fraction recorded by the high-speed camera and the axial distance of the shock tube is as Figure 5 shown. It can be seen from the figure that from the initial moment of t = 0 to the moment of t = 280 ms, the peak volume fraction of the particles decreases from 22% to 5%. Due to the uniform static suspended particle bed, the volume fraction of the particles changes symmetrically along the axial direction of the test section shock tube, and the peak volume fraction gradually decreases with the movement of the particles.

[0074] Thus, it can be seen that the present invention can make the particle bed uniformly and statically suspended in the shock tube, which is more convenient for observing and analyzing experiments on behaviors and laws such as shock wave reflection and transmission, and changes in the thickness of the particle bed. By using the method of placing partition plates at different distances to change the volume fraction, the airtightness and smoothness of the device can be increased, making the obtained experimental results more accurate.

Claims

1. A magnetically levitated gas-solid two-phase shock tube experimental device, comprising a high-pressure gas section (2), a bursting diaphragm (3), a gas pressure section (4), a circular-to-square transition section (5), a first square tube section (6), a visualization test section (7), a second square tube section (12) and a collection box (13); the outlet end of the high-pressure gas cylinder (1) is sequentially connected to the inlet section of the first square tube section (6) after passing through the high-pressure gas section (2) and the gas pressure section (4), and the gas pressure section (4) and the first square tube section (6) are connected through the circular-to-square transition section (5). A bursting diaphragm (3) is provided between the ports of the high-pressure gas section (2) and the gas pressure section (4) in butt joint. The outlet end of the first square tube section (6) is sequentially connected to the collection box (13) after passing through the visualization test section (7) and the second square tube section (12); It is characterized in that: Grooves are provided on both sides of the inner top surface and the inner bottom surface of the visualization test section (7). In each groove, a partition plate (11) is hingedly installed through a partition plate fixing nut (18) and a partition plate connecting rod (19). The partition plate connecting rod (19) passes through and is fixedly connected to the partition plate (11). Both ends of the partition plate connecting rod (19) are movably installed on the side wall of the visualization test section (7) and a partition plate fixing nut (18) is installed at the end for limiting; the partition plate connecting rod (19) serves as the rotation axis of the partition plate (11), and the rotation axis of the partition plate (11) is located on one side close to the center of the visualization test section (7); the two partition plates (11) on both sides of the inner top surface of the visualization test section (7) are symmetrically arranged with respect to the center of the visualization test section (7), and the two partition plates (11) on both sides of the inner bottom surface of the visualization test section (7) are symmetrically arranged with respect to the center of the visualization test section (7); the end of the partition plate connecting rod (19) is connected to an external rotation drive source, which drives the partition plate connecting rod (19) to rotate, thereby driving the partition plate (11) to rotate and fall to the vertical position to block the flow of the visualization test section (7). Then, after the two partition plates (11) fall, an internal closed space is formed inside the visualization test section (7), and there are particles in the closed space; a detachable electromagnetic coil (8) is installed above and below the outside of the visualization test section (7). The axial directions of the two detachable electromagnetic coils (8) are coaxially arranged vertically and are symmetrically arranged above and below the visualization test section (7); the two detachable electromagnetic coils (8) are both connected to an adjustable DC power supply (9). The detachable electromagnetic coils (8) are driven by the adjustable DC power supply (9) to be energized to generate an electromagnetic field. The electromagnetic field exerts an anti-gravity force vertically upward on the particles. By adjusting the magnitude of the current passing through the detachable electromagnetic coil (8), the particles in the internal closed space surrounded by the partition plates (11) form a statically levitated particle bed under the balance of the magnetic force and the gravity; a first pressure sensor (17) and a second pressure sensor (16) are installed on the first square tube section (6) at intervals along the bursting direction, and a third pressure sensor (15) and a fourth pressure sensor (14) are installed on the second square tube section (12) at intervals along the bursting direction; The length dimensions of the two partition plates (11) on both sides of the inner top surface of the visualization test section (7) are the sum of the upper and lower inner diameter dimensions of the visualization test section (7) and the thickness dimension of the groove; The length dimensions of the two partition plates (11) on both sides of the inner bottom surface of the visualization test section (7) are the sum of the upper and lower inner diameter dimensions of the visualization test section (7) and the thickness dimensions of the two grooves.

2. A magnetically levitated gas-solid two-phase shock tube experimental device according to claim 1, characterized in that: The rotation axes of the two partition plates (11) on both sides of the inner top surface of the visualization test section (7) are closer to the center of the visualization test section (7) than the rotation axes of the two partition plates (11) on both sides of the inner bottom surface of the visualization test section (7), forming a staggered distribution of the upper and lower groups of partition plates (11); the distance between the two partition plates (11) on both sides of the inner top surface of the visualization test section (7) is d, and the distance between the two partition plates (11) on both sides of the inner bottom surface of the visualization test section (7) is 3d.

3. A magnetically levitated gas-solid two-phase shock tube experimental device according to claim 1, characterized in that: By adjusting the current intensity of the electromagnetic coil (8), the control of the particle suspension and the particle volume fraction in the internal enclosed space surrounded by the partition plate (11) is realized.

4. A magnetically levitated gas-solid two-phase shock tube experimental device according to claim 1, characterized in that: By adjusting different combinations of the two partition plates (11) to fall to form internal enclosed spaces of different sizes and positions, the control of particle suspension and particle volume fraction in the gas-solid two-phase shock tube experiment is realized.

5. A magnetically levitated gas-solid two-phase shock tube experimental device according to claim 1, characterized in that: The visualization test section (7) is made of a transparent material.

6. A magnetically levitated gas-solid two-phase shock tube experimental device according to claim 1, characterized in that: The coil winding of the electromagnetic coil (8) meets the following setting requirements: Among them, z(n) represents the position of the coil along the Z direction corresponding to the number of turns of the coil per meter being n, and the z direction is the vertical direction; v is the volume of a single particle, μ 0 is the vacuum permeability of the particle, M ￥ is the saturation magnetization of the material of the particle, n is the number of turns of the coil per meter, n 0 represents the number of turns of the coil at the initial position when the z direction is zero, I is the current magnitude of the coil, γ characterizes the magnetic induction characteristics of the particle, and c is a constant.

7. An experimental method applied to the magnetically levitated gas-solid two-phase shock tube experimental device according to any one of claims 1-5, characterized in that: Using the device according to any one of claims 1-5, with the initial high-pressure gas cylinder (1) not opened, the two partition plates (11) are driven by the partition connecting rod (19) to rotate and fall to the vertical position, and the particles with the weight measured and recorded are placed in the internal enclosed space surrounded by the two partition plates (11), and the particles are evenly distributed in the internal enclosed space by vibration; Then, the adjustable DC power supply (9) is turned on to energize the electromagnetic coil (8) to generate an electromagnetic field, and the current of the electromagnetic coil (8) is adjusted to suspend the particles in the internal enclosed space and form a uniformly distributed static suspension particle bed, and the video image of the particle bed in the visualization test section (7) is collected through a high-speed camera; Next, open the high-pressure gas cylinder (1) to create a pressure ratio between the high-pressure section (2) and the pressure section (4). Use the method of bursting the bursting diaphragm (3) to generate a shock wave. The shock wave passes through the pressure section (4), the circular-to-square transition section (5), and the first square pipe section (6) in sequence, and then enters the visualization test section (7). After the shock wave passes through the visualization test section (7) and impacts the static suspended particle bed, it enters the collection box (13) through the second square pipe section (12). When the shock wave impacts and collides with the static suspended particle bed in the visualization test section (7), a schlieren instrument is used to reflect the shock wave-particle interaction and particle-particle interaction generated by the shock wave and particle collision at the visualization test section (7) into an image. At the same time, a high-speed camera is used to record the image, and the decay change of the shock wave Mach number is obtained by collecting pressure data through four pressure sensors (14-17), completing the gas-solid two-phase shock tube experiment.

8. An experimental method according to claim 7, characterized in that: The decay change of the shock wave obtained by collecting pressure data through four pressure sensors (14-17) is specifically obtained by the following method: 1) The velocity V of the shock wave is calculated using the following formula based on the axial spacing between the first pressure sensor (17) and the second pressure sensor (16) and the time difference between the pressure data collected by the first pressure sensor (17) and the second pressure sensor (16) respectively S : Wherein, d represents the axial distance between the first pressure sensor (17) and the second pressure sensor (16), t 0 , t 1 respectively represent the moments when the shock wave passes through the first pressure sensor (17) and the second pressure sensor (16); Furthermore, the Mach number M of the incident shock wave is calculated and obtained. S : where a 0 is the local speed of sound; 2) The Mach number of the shock wave is calculated in the same way as in step 1) using the pressure data collected by the third pressure sensor (15) and the fourth pressure sensor (14). 3) The difference obtained by subtracting the Mach number of the shock wave obtained in step 2) from the Mach number of the incident shock wave obtained in step 1) is used as the decay change of the shock wave Mach number.

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