Test device suitable for simulating two-dimensional impact test of particle flow under microgravity condition

Abstract

The application provides a test device suitable for two-dimensional impact test of particle flow under simulated microgravity conditions, which comprises a test box, a balancing system, a power and control system and a measuring system, wherein the test box comprises a box body and a test table, the test table is supported in the box body; the balancing system is used for adjusting the horizontal degree of the test box and the test table and the gravity acceleration value of the plane where the test table is located; the power and control system is used for providing power and driving control for the equipment in the device; and the measuring system is used for monitoring the whole process from the initial flow to the impact and to the final stability. The application can obtain the movement law of the particle flow in the microgravity environment under a relatively easy-to-control and low-cost environment, lays a certain test foundation for three-dimensional microgravity tests such as drop tower test and space station test, thereby promotes the understanding of engineering problems and geological problems under the extraterrestrial microgravity environment, and has important engineering application prospect and scientific value.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of research on the motion of granular media in microgravity field, and relates to a device suitable for simulating microgravity in a two-dimensional plane under normal gravity field. BACKGROUND

[0002] The existing research results show that in the microgravity environment, the mechanical properties of rock-soil body and granular media are significantly different from those on the ground. The change of the medium contact mode and the motion mode of the particles after force causes the significant change of the macroscopic properties of the particle system. However, there are few devices for studying the macroscopic properties and motion rules of particle flow in different gravity fields, and the mechanism has not been completely revealed. Therefore, it is particularly important to study and understand it.

[0003] However, the cost of directly conducting related tests in space environment is too high. Using liquid to simulate microgravity environment on the ground for research will be strongly disturbed by water resistance, which challenges the accuracy of the research, and such setting is only suitable for low-speed physical and mechanical tests. SUMMARY

[0004] In view of the problems in the prior art, the present application provides a test device suitable for simulating two-dimensional impact test of particle flow under microgravity condition. The test device can simulate the gravity acceleration field of 0-9.8 m / s 2 under ground environment in a relatively convenient and high-precision manner, and study the two-dimensional impact behavior and motion rules of particle flow. The test device enables the motion rules of particle flow in microgravity environment to be obtained in a relatively easy-to-control and low-cost environment, thereby promoting the understanding of engineering problems and geological problems under extraterrestrial microgravity environment, and having important engineering application prospect and scientific value. In addition, the test device also has the ability to perform gas pressure variable research. This comprehensive research method not only improves the accuracy of the test, but also enables the problems that may be encountered in the microgravity environment to be understood and solved more comprehensively.

[0005] To achieve the above-mentioned purpose, the technical solutions of the present application are as follows:

[0006] The test device suitable for simulating two-dimensional impact test of particle flow under microgravity condition comprises a test box, a balancing system, a power and control system, and a measurement system, wherein:

[0007] The test box comprises a box and a test table, and the test table is supported in the box.

[0008] The balancing system is used to adjust the horizontal degree of the test box and the test table, and the gravity acceleration value of the plane where the test table is located.

[0009] The power and control system is used for providing power and driving control for the equipment of the test box, the balance system and the measuring system.

[0010] The measuring system is used for monitoring the whole process motion and dynamic information of the test from the initial flow of the particles to the impact and to the final stability.

[0011] Compared with the prior art, the present application has the following advantages:

[0012] (1) The two-dimensional plane adjustable micro-gravity particle flow impact test can be realized in the normal gravity environment, which lays a certain test foundation for the test in the real micro-gravity environment.

[0013] (2) High-precision simulation and monitoring of complex working condition test. In the test, by adjusting the particle diameter, initial velocity, micro-gravity field, flow section distance and other parameters, the complex working conditions of different scales and characteristics of the rock-soil materials in the multi-micro-gravity field can be accurately simulated and monitored, and the shear flow law and flow impact characteristics of the particle rock-soil medium in the micro-gravity field can be effectively revealed.

[0014] (3) The test cost is relatively low, the maintenance is simple, the multiple repeated tests can be quickly carried out, and the equipment has great potential for subsequent modification. DETAILED DESCRIPTION

[0015] Figure 1 Whole schematic view of the test device of the embodiment;

[0016] Figure 2 Perspective view of the test box of the embodiment;

[0017] Figure 3 Front view of the test box of the embodiment;

[0018] Figure 4 Side view of the test box of the embodiment;

[0019] Figure 5 Front view of the test table of the embodiment;

[0020] Figure 6 Top view of the test table of the embodiment.

[0021] Markings in the figure:

[0022] Box 1, main beam 11, welding frame 12;

[0023] Test table 2, test plane 21, pneumatic boost rod 22, particle storage bin 23, particle storage bin inner side slide rail 231, particle medium 24, reed 25, blocking structure 26, scraper 27, scraper slide rail 271, inlet 28, outlet 29;

[0024] Elevation adjustment knob 31, level 32, main adjustment knob 331, main adjustment knob support 332, main adjustment knob transmission rod 333, secondary adjustment knob 341, secondary adjustment knob support 342, secondary adjustment knob transmission rod 343, gravity acceleration adjustment knob 35;

[0025] Pressure sensor 41, PIV camera 42, PIV positioning point 421;

[0026] Pneumatic pump 51, vacuum pump 52, pneumatic and reed control console 53, control host 54. DETAILED DESCRIPTION

[0027] The technical solutions provided by the present application will be further described below in combination with specific embodiments and their accompanying drawings. The advantages and features of the present application will be more apparent in combination with the following description.

[0028] The test device is suitable for simulating a two-dimensional impact test of particle flow under a microgravity condition, and comprises a test box body, a balancing system, a power and control system, and a measurement system. The test device is used for realizing particle medium flow impact tests under different microgravity conditions in a two-dimensional plane under a ground normal gravity condition, and quantitatively and high-precisely monitoring motion and dynamic information of the whole process from initial flow to impact to final stability.

[0029] The test box body comprises a box body 1 and a test table 2, and the test table is supported in the box body through a rigid support;

[0030] The box body 1 comprises a bottom plate and left and right side plates;

[0031] The test table 2 is a closed hollow structure, and is internally provided with a test plane 21, a pneumatic boost rod 22, a particle storage bin 23, particle medium 24, a reed 25, a blocking structure 26, and a scraper 27, wherein:

[0032] The test plane 21 is a two-dimensional plane, and the distance between the test plane and the upper surface of the test table is adjustable; in order to improve test precision, the test plane in the embodiment is an ultralow-friction high-rigidity smooth light-tight test plane;

[0033] The particle storage bin 23 is arranged on the test plane, and is used for storing the particle medium 24;

[0034] The pneumatic boost rod 22 is arranged on the left side of the particle storage bin 23, and is used for pushing the particle storage bin to apply kinetic energy to the particle medium in the bin;

[0035] The reed 25 is arranged on the right side of the particle storage bin 23, and is used for limiting displacement of the particle medium before the test; the reed can be synchronously displaced with the particle storage bin and is quickly opened and closed. The embodiment adopts a high-elasticity gate reed, which can be quickly retracted and reduces the influence on the particle flow state; the maximum displacement amount of the reed is slightly greater than the activity amount of the pneumatic boost rod, and the reed is electronically controlled to be retracted.

[0036] A barrier structure 26 is arranged opposite the particle storage bin 23 and is used to block the flow of particles. The barrier structure is designed to be detachable.

[0037] A scraper 27 is used to clean and recycle the particle medium. In the embodiment, the scraper is a movable scraper and is provided with a scraper sliding rail 271 to facilitate movement of the scraper.

[0038] The test bench is also provided with an inlet 28 and an outlet 29. The inlet is opposite the particle storage bin, and the outlet is adjacent to the barrier structure.

[0039] In the embodiment, the size of the box 1 is: length 1600 mm, width 900 mm, and height 1300 mm. The size of the test bench is: length 1400 mm, width 800 mm, and height 50 mm.

[0040] In the embodiment, three pneumatic boost rods are provided, with a movable range of 50 mm and a maximum speed of 0.4 m / s. The particle storage bin 23 can define the initial two-dimensional shape of the particle medium through the inner slide rail 231 and ensure the stability of the initial state, and will not be deformed before the reed is retracted.

[0041] Further, the rigid support includes a main beam 11 and a plurality of welding supports 12, and the welding supports 12 are arranged on the main beam 11. The main beam is supported on the left and right side plates of the box, and the test bench is connected to the main beam through the welding supports.

[0042] Further, the box is not provided with front and rear side plates to allow the test bench to rotate to achieve different gravitational accelerations in the plane at different angles.

[0043] The balancing system is used to adjust the level of the test box and the test bench and the gravitational acceleration value of the plane on which the test bench is located, and includes elevation adjustment knobs 31, a level 32, a main adjustment knob 331, a main adjustment knob support 332, a main adjustment knob transmission rod 333, a secondary adjustment knob 341, a secondary adjustment knob support 342, a secondary adjustment knob transmission rod 343, and a gravitational acceleration adjustment knob 35.

[0044] The elevation adjustment knobs 31 are four in number and are arranged at the four corners of the bottom of the box to control the level of the box.

[0045] The main adjustment knob 331 is arranged on the side wall of the test bench and is connected to the main adjustment knob support 332 arranged on the bottom plate of the test bench through the main adjustment knob transmission rod 333, and is used to adjust the distance between the test plane 21 of the test bench and the upper surface of the test bench to adapt to particle media of various sizes.

[0046] Two sub-positioning knobs 332 are arranged on the two side walls of the test table, and are connected with a sub-positioning knob support 342 arranged on the bottom plate of the test table through a sub-positioning knob transmission rod 343, and are used for adjusting the horizontal degree of the test plane.

[0047] Four levels are arranged, two of which are arranged on the bottom plate of the box body and are used for assisting in adjusting the horizontal degree of the box body, and the other two are arranged on the test plane of the test table and are used for assisting in adjusting the horizontal degree of the test plane.

[0048] A gravity acceleration adjusting knob 35 is arranged on the main beam 11 of the rigid support, and is used for controlling the micro-gravity in the test table. Specifically, the gravity acceleration adjusting knob is connected with the main beam 11 of the rigid support, and the gravity acceleration adjusting knob is used for adjusting the inclination angle of the test table, so that the gravity acceleration represented on the test plane is changed. The gravity acceleration adjusting knob 35 is provided with a scale for displaying the current gravity acceleration value.

[0049] Further, the main position adjusting knob 331 is provided with a scale to represent the distance between the test plane and the upper surface of the test table. In the embodiment, the adjustable range is 15 mm.

[0050] Preferably, the main position adjusting transmission rod and the sub-positioning transmission rod adopt high-rigidity rod members to avoid excessive elastic deformation affecting the test.

[0051] The power and control system comprises a pneumatic pump 51, a vacuum pump 52, a pneumatic and reed control console 53, and a control host 54, wherein:

[0052] The pneumatic pump 51 is connected with the pneumatic boost rod 22 and is used for driving the pneumatic boost rod. The pneumatic pump 51 can be arranged on the inside or outside of the box body.

[0053] The vacuum pump 52 is used for fully evacuating the test table before the test, and can be arranged on the inside or outside of the box body.

[0054] The pneumatic and reed control console 53 is used for electronically controlling the pneumatic boost rod 22 and the reed 25, and is arranged on the outside of the box body. The working logic of the pneumatic and reed control console 53 is that the reed 25 is closed between the reed 25 and the particle storage bin 23 before the pneumatic rod is started. When the maximum range is reached, the reed 25 is triggered to retract, so that the particle storage bin 23 releases the particle medium. The reed can also be controlled independently.

[0055] The control host 54 is used for realizing test condition control and test data acquisition, and can be arranged on the inside or outside of the box body. Specifically:

[0056] The control host 54 is connected with the pneumatic pump 51, the reed 25, and the pneumatic and reed control console 53. The pneumatic pump parameters can be set, mainly including the initial speed of the sample. The pneumatic pump 51 and the reed 25 can be operated through the pneumatic and reed control console 53, so as to control the speed of the pneumatic boost rod 22 and control the ejection and retraction of the reed 25.

[0057] The control host 54 is connected with the vacuum pump 52 for controlling the vacuum degree of the test bed;

[0058] The control host 54 is connected with the scraper 27 for controlling the displacement and lifting angle of the scraper, and realizing the control of the granular medium recovery;

[0059] The control host 54 is connected with the PIV and the pressure sensor of the measuring system for collecting the data of the test process, including the image data collected by the PIV and the stress value data of the blocking structure collected by the pressure sensor.

[0060] It should be noted that the analysis and processing of the moving image and the force data are not the technical problems to be solved by the present application, and do not constitute the technical scheme of the present application.

[0061] The measuring system comprises a PIV (Particle Image Velocimetry) camera 42 and a holder, and a pressure sensor 41, so as to effectively record the motion trajectory of the granular flow and the contact relationship between the granular flow and the blocking structure;

[0062] The PIV camera 42 is arranged on the holder and can automatically keep vertical to the test plane, and is used for monitoring and recording the motion information of the granular flow, so as to realize the synchronous high-precision monitoring of the macroscopic granular flow motion law and the microscopic granular migration law, and analyze the speed and displacement law. Further, the PIV positioning point 421 can be arranged on the test bed for positioning and dimensioning.

[0063] The pressure sensor 41 is arranged on the blocking structure 26 in the test bed, and is used for collecting the stress of the blocking structure, so as to study the mechanical contact law of the granular flow and the blocking structure. Multiple pressure sensors can be arranged on the blocking structure for multi-point measurement. The embodiment adopts a millimeter-level micro high-frequency stress sensor for multi-point measurement of the stress of the blocking structure.

[0064] Further, the PIV camera 42 and the pressure sensor 41 are connected with the control host 54 of the power and control system, and the collected data is uploaded to the control host 54.

[0065] The test device of the present application can create a nearly microgravity test condition for the granular flow research in a two-dimensional plane under the condition of normal gravity.

[0066] After the size and material of the test particles are selected, the preparation before the test and the test operation are performed as follows.

[0067] Preparation stage:

[0068] (1) Adjust the level of the box body 1:

[0069] Adjust the level of the box by four elevation adjustment knobs 31 and two level meters 32 on the box;

[0070] (2) Adjust the level of the test plane:

[0071] Adjust the distance between the test plane and the upper surface of the test table to be slightly larger than the diameter of the test particles by adjusting the main adjustment knob 331, and adjust the level of the test plane by two auxiliary adjustment knobs 341 and two level meters 32 on the test plane;

[0072] (3) Initialize the pneumatic boost rod 22 and the reed 25 by the pneumatic and reed control console 53, fill the test particles through the inlet 28, close the inlet 28 and the outlet 29, and use the vacuum pump 52 to vacuum the test table 2;

[0073] (4) Adjust the required gravity acceleration scale by the gravity acceleration adjustment knob 35, and fix it after adjustment;

[0074] (5) Check the test equipment, including: test PIV monitoring equipment status and parameters, whether the pressure sensor is working normally, whether the particle recovery scraper can be normally popped up, whether the level meters of the box are still level, etc.

[0075] Test phase:

[0076] (1) Set the initial energy of the particles on the control host (computer), operate the pneumatic and reed control console 53, push the particle storage bin 23 by the pneumatic boost rod 33, apply corresponding kinetic energy to the particle medium 24 in the bin, the reed 25 and the particle storage bin 23 are displaced synchronously, and the reed 25 is automatically and quickly retracted after reaching the limit, the particle storage bin 23 releases the particle medium, and impacts the blocking structure 26;

[0077] At the same time, the PIV camera records the whole process, so that the speed and displacement can be analyzed after the test; after the particle medium contacts the blocking structure, multiple miniature high-frequency stress sensors on the blocking structure can quickly measure and record the contact force of the particle medium;

[0078] (2) After the particle energy is dissipated stably, the test is completed, the particle recovery scraper 27 is popped up, the particle medium is "swept" to the outlet, the particle medium is recovered, and the process is repeated several times; after the recovery is completed, the next test can be performed.

[0079] In this application, the adjustable test plane is very convenient for tests under different microgravity conditions, and particle media with a diameter of at least 15mm and at most 30mm can be selected to simulate different working conditions of the fluidized material. If necessary, the test particles can be replaced by MEMS (Micro Electro Mechanical Systems) particles to realize intelligent monitoring of more parameters.

[0080] Leveling the chamber and plane before the experiment ensured experimental accuracy. The initial velocity of the particle flow could be infinitely adjusted by regulating the initial speed of the pneumatic booster. After the particle medium came into contact with the barrier structure, the pressure sensor of the barrier structure continuously collected data on the contact force of the particle medium at a sampling frequency of over 100 times / second, while PIV monitoring throughout the process ensured complete monitoring of the particle flow's motion and trajectory. The scraper enabled the recovery of test particles, ensuring the rapid commencement of the next experiment.

[0081] This experimental device can effectively reflect the flow and impact characteristics of particulate media in a two-dimensional plane, laying a certain experimental foundation for three-dimensional microgravity experiments such as drop tower tests and space station tests, and providing reliable experimental data.

[0082] The above description is merely a description of preferred embodiments of this application and is not intended to limit the scope of this application in any way. Any changes or modifications made by those skilled in the art based on the above-disclosed technical content should be considered as equivalent and valid embodiments and fall within the scope of protection of the technical solution of this application.

Claims

1. A test apparatus suitable for simulating two-dimensional impact tests of particle flow under microgravity conditions, characterized in that, It includes the test chamber, balancing system, power and control system, and measurement system, among which: The test chamber includes a chamber (1) and a test bench (2), wherein the test bench is supported in the chamber by a rigid bracket; The balancing system is used to adjust the levelness of the test chamber and the test platform, as well as the gravitational acceleration value of the plane on which the test platform is located; The power and control system is used to provide power and drive control for the equipment of the test chamber, the balancing system and the measurement system; The measurement system is used to monitor the motion and dynamics of the test particles throughout the entire process from initial flow to impact and finally stabilization. The test bench (2) is a closed hollow structure, and its interior is equipped with a test plane (21), a pneumatic booster rod (22), a particle storage chamber (23), a particle medium (24), a spring (25), a barrier structure (26), and a scraper (27), wherein: The test plane (21) is a two-dimensional plane, and its distance from the upper surface of the test platform is adjustable; The particle storage chamber (23) is set on the test plane to store the particle medium (24). A pneumatic booster (22) is located on the left side of the particle storage chamber (23) and is used to push the particle storage chamber to apply kinetic energy to the particle medium inside the chamber. A reed (25) is located on the right side of the particle storage chamber (23) to limit the displacement of the particle medium before the test. The reed can move synchronously with the particle storage chamber and open and close quickly. The barrier structure (26) is positioned opposite the particle storage chamber (23) and is used to block the particle flow; Scraper (27) is used to sweep and recover particulate media; The test bench is also equipped with an inlet (28) and an outlet (29). The inlet is directly opposite the particle storage bin, and the outlet is near the barrier structure. The balancing system includes: an elevation adjustment knob (31), a level (32), a main adjustment knob (331), a main adjustment knob bracket (332), a main adjustment knob transmission rod (333), a secondary adjustment knob (341), a secondary adjustment knob bracket (342), a secondary adjustment knob transmission rod (343), and a gravity acceleration adjustment knob (35), wherein: There are four elevation adjustment knobs (31), which are respectively set at the four corners of the bottom of the box (1) to control the level of the box; The main adjustment knob (331) is located on the side wall of the test bench and is connected to the main adjustment knob bracket (332) located on the bottom plate of the test bench via the main adjustment knob transmission rod (333). It is used to adjust the distance between the test plane and the upper surface of the test bench to accommodate particle media of various sizes. Two secondary adjustment knobs (341) are respectively set on the two side walls of the test bench, and are connected to the secondary adjustment knob bracket (342) set on the bottom plate of the test bench through the secondary adjustment knob transmission rod (343) to adjust the level of the test plane; Level (32), a total of four, two of which are set on the bottom plate of the box to assist in adjusting the level of the box, and the other two are set on the test surface of the test bench to assist in adjusting the level of the test surface; The gravitational acceleration adjustment knob (35) is connected to the rigid support. By adjusting the tilt angle of the test platform, the gravitational acceleration represented on the test plane is changed accordingly.

2. The test apparatus as described in claim 1, characterized in that, The test chamber: The box body (1) includes a bottom plate and left and right side plates; The rigid support includes a main beam (11) and multiple welding frames (12), the welding frames (12) being disposed on the main beam (11); the main beam is supported on the left and right side plates of the box body, and the test bench is connected to the main beam through the welding frames.

3. The test apparatus as described in claim 1, characterized in that, The gravity acceleration adjustment knob (35) is provided with a scale to display the current gravity acceleration value; The main adjustment knob (331) has a scale to indicate the distance between the test plane and the upper surface of the test platform.

4. The test apparatus as described in claim 1, characterized in that, The power and control system includes: a pneumatic pump (51), a vacuum pump (52), a pneumatic and reed control console (53), and a control host (54), wherein: A pneumatic pump (51) is connected to a pneumatic booster rod (22) inside the test bench and is used to drive the pneumatic booster rod; A vacuum pump (52) is used to fully evacuate the test bench before the test. The pneumatic and reed control console (53) is connected to the pneumatic booster rod (22) and reed (25) in the test bench and is used for electronic control of the pneumatic booster rod (22) and reed (25). The control host (54) is used to control test conditions and acquire test data. Specifically: The control host (54) is connected to the pneumatic pump (51), the reed (25), and the pneumatic and reed control console (53) to set the parameters of the pneumatic pump, mainly including the initial velocity of the sample, and to operate the pneumatic pump (51) and the reed (25) through the pneumatic and reed control console (53) to control the speed of the pneumatic push rod (22) and the pop-up and retraction of the reed (25); The control host (54) is connected to the vacuum pump (52) and is used to control the vacuum level of the test bench; The control host (54) is connected to the scraper (27) to control the scraper displacement and lifting angle, thereby realizing particulate media recovery control; The control host (54) is connected to the measurement system and is used to collect motion images and force data during the test.

5. The test apparatus as described in claim 1, characterized in that, The measurement system includes a PIV camera (42) and a pan-tilt unit, and a pressure sensor (41), wherein: A PIV camera (42) is mounted on a pan-tilt unit for monitoring and recording particle flow motion information; Pressure sensor (41) is installed on the barrier structure (26) inside the test bench to collect the stress on the barrier structure. Multiple pressure sensors are installed on the barrier structure for multi-point measurement.

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