A small celestial body excitation sampling and air-blowing sample vacuum experimental verification system

Abstract

The application discloses a small celestial body excitation sampling and air-blow sampling vacuum experimental verification system, a PIV flow velocity measuring system is arranged outside a to-be-measured pipe section of a sampling pipeline, flow field characteristic experimental verification is carried out by measuring the flow velocity of tracer particles in the sampling pipeline, a high-speed photography system is arranged outside the to-be-measured pipe section of the sampling pipeline, particle characteristic experimental verification is carried out by measuring the flow velocity of simulated asteroid particles, a signal acquisition system is used for synchronously measuring the gas pressure of all measuring points of the to-be-measured pipe section of the sampling pipeline and real-time monitoring of the vacuum degree in a vacuum cabin, and a control system is used for controlling the working time sequence of each system. The application can carry out gas excitation sampling and air-blow sampling verification under the ground gravity vacuum environment, and the flow velocity and distribution of the flow field can be measured.

Description

Technical Field

[0001] This invention relates to the field of ground-based experimental technology for space exploration, specifically to a vacuum experimental verification system for small celestial body excitation sampling and gas-blown sample delivery. Background Technology

[0002] In high-vacuum, microgravity space exploration environments, gas-directed excitation is an efficient and reliable sample collection method. The entire system involves gas supply components, sample delivery nozzles, delivery pipelines, and sample packaging containers. During the collection of stellar regolith, the gas flow enters the vacuum environment from high pressure, rapidly expands, and then carries stellar regolith particles at hypersonic speeds along a slender sample delivery pipeline. The stellar regolith reaches the sample packaging container, where gas-solid separation is achieved through filtration. Throughout the sampling process, the gas flow field structure within the delivery path is complex, exhibiting phenomena such as shock wave interactions and shock wave-boundary layer interference. Ground-based experimental systems are needed to simulate the high-vacuum, microgravity environment to verify the flow field transport characteristics and particle motion features of the sample collection device.

[0003] The main challenge of the ground-based verification experimental system for the sampling and delivery process of small celestial bodies is simulating the high vacuum (~10) of the target small celestial body. -11 Pa) and weak gravity (~10 -5 g) Sampling environment. Currently, commonly used methods for simulating vacuum environments mainly employ vacuum systems of different sizes and pump capacities. The former limits the dynamic vacuum level during the experiment, while the latter determines the initial vacuum level of the environment before the experiment. Microgravity simulation methods include drop tower methods, weightless aircraft, lightweight spherical soil, water flotation, air flotation, and suspension methods. The first three methods mainly simulate dynamic processes, while the latter three are mainly used to simulate static gravity equilibrium.

[0004] Domestic and international research indicates that drop towers and zero-gravity aircraft are more suitable for simulating microgravity environments in space. Both methods have low residual acceleration, enabling the simulation of microgravity in sample movement. Specifically, Japan's Hayabusa2 mission used the ZARM drop tower at the University of Bremen, Germany, to conduct impact sampling and spike retrieval verification experiments. During these experiments, a vacuum chamber system was used to simultaneously simulate a vacuum environment. The sampling objects were glass beads (with particle sizes ranging from several hundred micrometers to 1 mm and 1–4 mm). Observation utilized a transparent shell and high-speed photography, and comparisons were made with ground-based experiments. The results showed that microgravity is beneficial for sampling, with the sample volume approximately 10 times that obtained under Earth's gravity. The US OSIRIS mission, to simulate the microgravity environment of an asteroid, conducted four phases of zero-gravity aircraft experiments. The first two phases primarily verified the principle of gas excitation, while the latter two phases primarily verified the sampling capability after the product's state was determined. These experiments did not simulate a vacuum environment; the sampling objects were small-particle graded asteroid regolith. High-speed photography was used for observation, and comparisons were made with ground-based experiments. The sample volume obtained under zero-gravity conditions was at least 4–5 times that under ground gravity conditions.

[0005] The two environmental experiments described above can achieve good microgravity conditions in a short period of 5–10 seconds, but the short experimental time and high cost, coupled with the limited space of the drop tower and the zero-gravity aircraft, result in two situations: 1) the initial vacuum level can only reach ~10 Pa; 2) the dynamic vacuum level quickly reaches the order of kPa under blowing conditions. These two points indicate that during the experiment, the distance from the target small celestial body is ~10 Pa. -11 Significant differences in Pa lead to distortion in the simulation of high-vacuum experimental environments. Summary of the Invention

[0006] In view of this, the present invention provides a small celestial body excitation sampling and gas blowing sample vacuum experimental verification system, which can perform gas excitation sampling and gas blowing sample verification under ground gravity vacuum environment, and measure the flow velocity and distribution of the flow field.

[0007] The technical solution adopted in this invention is as follows:

[0008] A vacuum experimental verification system for small celestial body excitation sampling and gas blowing sample delivery includes a vacuum chamber, a sample delivery pipeline, a gas supply system I, a gas supply system II, a tracer particle generator, a control system, a PIV flow rate measurement system, a high-speed photography system, and a signal acquisition system.

[0009] The gas supply system I is connected in series with the tracer particle generator. The gas supply ports of the gas supply system I are located at the inlet and middle of the sample delivery pipe, used to provide tracer particles and excite simulated stellar soil particles. The gas supply ports of the gas supply system II are located at the beginning and middle sections of the sample delivery pipe, used to blow away tracer particles adhering to the inner wall of the pipe. The sample delivery pipe and the tracer particle generator are both located inside the vacuum chamber. The PIV velocity measurement system is located outside the section of the sample delivery pipe to be tested, and performs flow field characteristic experiments by measuring the flow velocity of the tracer particles in the sample delivery pipe. The high-speed photography system is located outside the section of the sample delivery pipe to be tested, and performs particulate matter characteristic experiments by measuring the flow velocity of simulated stellar soil particles. The signal acquisition system is used to simultaneously measure the gas pressure at all measuring points in the section of the sample delivery pipe to be tested and to monitor the vacuum level in the vacuum chamber in real time. The control system is used to control the working sequence of the gas supply system, the blowing system, the PIV velocity measurement system, and the high-speed photography system.

[0010] Furthermore, the formula for calculating the volume A of the vacuum chamber is as follows:

[0011]

[0012] Q is the sample gas flow rate, P g Let P be the gas pressure, and P be the dynamic vacuum level of the environment after gas excitation. A P A Greater than 2.5 × 10-1 Pa.

[0013] Furthermore, when the actual sampling process is the same as the acceleration of a single particle in the ground test, the density ρ of the simulated star soil particles is... p satisfy

[0014]

[0015] F represents the aerodynamic force acting on the simulated space soil particles in the airflow, m represents the mass of a single particle in the ground test, m0 represents the mass of a particle of the same volume with the same density as the space soil in orbit, and d represents the particle size of the simulated space soil particles.

[0016] Furthermore, the gas supply system I includes a nitrogen buffer tank, a pressure reducing valve, a flow meter, a solenoid valve, a trans-chamber flange, a pressure sensor, a sampling nozzle, a sample delivery nozzle, and pipelines;

[0017] A nitrogen buffer tank is supplied with nitrogen via a pipeline that extends into the vacuum chamber through a trans-chamber flange and is connected in series with a tracer particle generator. The trans-chamber flange is mounted on the vacuum chamber. The tracer particle generator is connected to a sampling nozzle and a delivery nozzle via pipelines. The sampling nozzle is located at the inlet of the delivery pipe, and the delivery nozzle is located in the middle of the delivery pipe. The pressure reducing valve and flow meter are installed on the pipeline between the nitrogen buffer tank and the trans-chamber flange. Solenoid valves are installed on the pipelines before and after the tracer particle generator and before the sampling nozzle. The pressure sensor is installed on the pipeline at the inlet of the delivery pipe to ensure the inlet pressure.

[0018] Furthermore, the PIV flow rate measurement system includes a laser, an internal light guide arm, an external light guide arm, a transmission and reflection mirror assembly, a quartz glass flange, and a sheet light module;

[0019] Both the internal and external light guide arms are equipped with transmission and reflection mirror groups. The laser and the external light guide arm are located outside the vacuum chamber, while the internal light guide arm is located inside the vacuum chamber. The quartz glass flange is fixed to the vacuum chamber. The laser beam emitted by the laser is reflected sequentially by the external and internal light guide arms and then focused onto the sheet light module. The sheet light module then splits and reflects the beam to the two test areas of the sample delivery pipe section.

[0020] Furthermore, the high-speed photography system includes an image processing platform, two high-speed cameras and matching LED light sources. The two high-speed cameras are located inside the vacuum chamber, corresponding to two test areas of the sample delivery pipe section to be tested, respectively. The data collected by the high-speed cameras is transmitted to the image processing platform outside the vacuum chamber. The image processing platform is connected to the laser through a synchronizer.

[0021] Furthermore, the test area of ​​the test section of the sample delivery pipe is made of quartz glass.

[0022] Beneficial effects:

[0023] 1. This invention proposes a method for gas-excited sampling and air-blowing sample verification under ground-based gravity vacuum environment using simulated stellar soil particles in a large ground-based vacuum chamber. Simultaneously, a non-contact particle image velocimetry (PIV) method is employed, utilizing micron-sized tracer particles mixed into the gas transport particle flow field to indirectly visualize and measure the flow velocity and distribution. This enables visualized dynamic monitoring of the air-blowing flow field under high vacuum, solving the problems of strong flow field interference, narrow measurement range, poor accuracy, and low time resolution of traditional measurement methods. Experiments were conducted on the effects of air-blowing sampling at different back pressures of 1.0e-3 Pa, 1.0e-1 Pa, ..., 500 Pa, achieving flow field characteristic acquisition with a velocity accuracy better than 10% and a time resolution of up to 100 ms.

[0024] 2. Based on the premise that the ground-to-orbit acceleration of particles are equal, this invention selects lightweight particles of a specific density to counteract the influence of ground gravity and obtains the motion characteristics of particles in the flow field. This can equivalently verify the on-orbit application of small celestial body gas excitation sampling and gas blowing sampling technology under vacuum microgravity environment.

[0025] 3. This invention uses low-density simulated star soil particles to verify gas blowing sampling under ground gravity vacuum environment. It realizes the verification of the combined effect of high vacuum and microgravity environmental conditions on gas sampling under the same experimental system, and overcomes the influence of ground tests such as gravity, particle collision, and particle-wall collision.

[0026] 4. Considering that the tracer particle generator itself has the characteristic of a buffer tank, which may cause instability in the gas path pressure, and that the number of tracer particles will decrease as the gas supply system pipeline grows during the experiment, in order to provide the required inlet conditions and ensure measurement quality, this invention places the tracer particle generator in a vacuum chamber to reduce the distance between the tracer particle generator and the sampling nozzle. At the same time, a three-electromagnetic valve scheme is used, that is, solenoid valves are set at three positions: before, after and before the tracer particle generator and before the main nozzle. The influence of the generator on the gas path pressure is reduced by timing control. Secondly, a pressure sensor is set on the pipeline at the inlet of the sample delivery pipeline to measure the pressure and ensure that the required inlet pressure is provided for the experiment. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the composition of the vacuum experimental verification system for small celestial body excitation sampling and air blowing sample delivery of the present invention.

[0028] Figure 2 This is a schematic diagram of the PIV flow velocity measurement system of the present invention.

[0029] Figure 3This is a schematic diagram of the coordinate system of the measurement points in the sampling end-to-end flow field characteristic measurement experiment of this invention.

[0030] Figure 4 This is a schematic diagram of the coordinate system of the measurement points in the sampling end-to-end particulate matter characteristic measurement experiment of this invention.

[0031] Figure 5 This is a flowchart illustrating the verification process of the present invention.

[0032] Among them, 1-Nitrogen buffer tank I, 2-Nitrogen buffer tank II, 3-Pressure reducing valve I, 4-Sputtering thin film pressure sensor I, 5-Sputtering thin film pressure sensor II, 6-Pneumatic hose I, 7-Flow meter I, 8-Flow meter II, 9-Secondary pressure reducing valve, 10-T-connector, 11-Tracer particle generator, 12-Solenoid valve for tracer particle blowing, 13-Manual valve, 14-Tracer particle gas path manual valve, 15-Compression fitting and ball joint, 16-Gas path through-chamber flange, 17-Solenoid valve before particle generator, 18-Particle generator... 19-Two-position three-way solenoid valve, 20-Pneumatic hose II, 21-Sputtered thin film pressure sensor III, 22-Sampling nozzle, 23-Micro differential pressure transmitter, 24-Sampling pipeline, 25-Optical module, 26-Indoor light guide arm, 28-Quartz glass flange, 29-Outdoor light guide arm, 30-Laser, 31-Synchronizer, 32-Image processing platform, 33-Camera circuit through-chamber flange, 34-High-speed camera, 35-Vacuum chamber, 36-Cable through-chamber flange, 37-Control system, 38-Sampling nozzle. Detailed Implementation

[0033] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0034] This invention provides a vacuum experimental verification system for small celestial body excitation sampling and gas-blown sample delivery, comprising three main parts: a vacuum chamber 35, a gas supply system, and a measurement system. A schematic diagram of the system configuration is attached. Figure 1 As shown. Specifically, the gas supply system is used to provide a stable pressure gas source to the inlet of the sample delivery pipeline 24 under different back pressures. The gas supply system includes gas supply system I, gas supply system II, and tracer particle generator 11; the measurement system includes control system 37, PIV flow rate measurement system, high-speed photography system, and signal acquisition system.

[0035] Gas supply system I is connected in series with tracer particle generator 11. The gas supply port of gas supply system I is located at the inlet and middle of sample delivery pipe 24, and is used to provide tracer particles and excite simulated stellar soil particles in vacuum chamber 35. The gas supply port of gas supply system II is located at the beginning and middle sections of sample delivery pipe 24, and is used to blow away tracer particles attached to the inner wall of the pipe. Sample delivery pipe 24 and tracer particle generator 11 are both located inside vacuum chamber 35.

[0036] The gas supply system I includes a nitrogen buffer tank I1, a pressure reducing valve group, a flow meter I7, a solenoid valve group, a gas passage flange 16, a pressure sensor group, a sampling nozzle 22, a sample delivery nozzle 38, and pipelines; the pipelines use pneumatic hoses, including pneumatic hose I6 and pneumatic hose II20.

[0037] Nitrogen buffer tank I1 (nitrogen cylinder and pressure stabilizing tank) is supplied with nitrogen through pneumatic hose I6. The buffer tank is chosen as the gas source to improve system stability. Pneumatic hose I6 extends into the vacuum chamber 35 through the gas passage flange 16 and is connected in series with the tracer particle generator 11. The pipeline is connected to the gas passage flange 16 via a compression fitting and a ball joint 15. The gas passage flange 16 is mounted on the vacuum chamber 35. The tracer particle generator 11 is connected to the sampling nozzle 22 and the sample delivery nozzle 38 through pneumatic hoses I6 and II20, respectively. The other end of pneumatic hose II20 is connected to the gas... The end of the flexible hose I6 is connected, the sampling nozzle 22 is located at the inlet of the sample delivery pipeline 24, and the sample delivery nozzle 38 is located in the middle of the sample delivery pipeline 24; the pressure reducing valve group and the flow meter I7 are installed on the pipeline between the nitrogen buffer tank I1 and the gas passage flange 16, and the tracer particle gas passage manual valve 14 is also installed on the pipeline after the flow meter I7. In this embodiment, the pressure reducing valve group includes a pressure reducing valve I3 and a secondary pressure reducing valve 9. The pressure reducing valve I3 is installed on the pipeline between the nitrogen buffer tank I1 and the flow meter I7, and the secondary pressure reducing valve 9 is installed on the pipeline between the flow meter I7 and the tracer particle gas passage manual valve 14. Solenoid valves are installed on the pipelines in front of and behind the tracer particle generator 11 and in front of the sampling nozzle 22, respectively: solenoid valve 17 before the particle generator, solenoid valve 18 after the particle generator, and two-position three-way solenoid valve 19; the pressure sensor group includes sputtered thin film pressure sensor I4 and sputtered thin film pressure sensor III21. Sputtered thin film pressure sensor I4 is installed on the pipeline between pressure reducing valve I3 and flow meter I7, and sputtered thin film pressure sensor III21 is installed on the pipeline at the inlet of the sample delivery pipeline 24 to measure pressure, ensuring that the required inlet pressure is provided for the experiment, and the differential pressure change in the sample delivery flow field is measured by a differential pressure transmitter 23 installed at the beginning of the sample delivery pipeline 24.

[0038] The gas supply system II includes a nitrogen buffer tank II2, a pressure reducing valve I3, a flow meter II8, a gas passage flange 16, a sputtering thin film pressure sensor II5, a solenoid valve 12 for tracer particle blowing, a manual valve 13, and pipelines; the pipelines use pneumatic hoses I6.

[0039] Nitrogen buffer tank II2 is supplied with gas via pneumatic hose I6. Using the buffer tank as the gas source improves system stability. Pneumatic hose I6 extends into the vacuum chamber 35 via the gas passage flange 16. Pneumatic hose I6 is split into two branches via a tee quick-connect fitting 10, connecting to the starting and middle sections of the sample delivery pipeline 24. Both branches are equipped with solenoid valves 12 for tracer particle blowing. Pressure reducing valve I3 and flow meter II8 are located on the pipeline between nitrogen buffer tank II2 and the gas passage flange 16. Sputtering diaphragm pressure sensor II5 is located on the pipeline between pressure reducing valve I3 and flow meter II8. A manual valve 13 is also located on the pipeline after flow meter II8.

[0040] The PIV flow velocity measurement system is set outside the test section of the sample delivery pipe 24. The flow field characteristics are experimentally verified by measuring the flow velocity of tracer particles inside the sample delivery pipe 24.

[0041] like Figure 2 As shown, the PIV flow velocity measurement system includes a laser 30, an internal light guide arm 26, an external light guide arm 29, a transmission and reflection mirror assembly, a quartz glass flange 28, and a sheet light module 25. The laser 30 is a Vlite-200 laser. Both the internal and external light guide arms 29 are equipped with transmission and reflection mirror assemblies. The laser 30 and external light guide arm 29 are located outside the vacuum chamber 35, while the internal light guide arm 26 is located inside the vacuum chamber 35. The quartz glass flange 28 is fixed to the vacuum chamber 35. The beam emitted by the laser 30 is reflected sequentially by the external and internal light guide arms 29 and then focused onto the sheet light module 25. The sheet light module 25 then splits and reflects the beam to two test areas on the sample delivery pipe 24. The sheet light module 25 utilizes spherical mirror focusing and reflection technology. By using the same laser 30 to provide a background light source for both test areas, synchronous measurement of gas velocities in the two measurement areas by the PIV is achieved.

[0042] The high-speed photography system is set outside the test section of the sample delivery pipe 24 to verify the particulate matter characteristics by measuring the flow velocity of simulated soil particles.

[0043] The high-speed photography system includes an image processing platform 32, a camera circuit through-chamber flange 33, two high-speed cameras 34, and matching LED light sources. The two high-speed cameras 34 are located inside the vacuum chamber 35, corresponding to two test areas of the sample delivery pipe 24. The matching LED light sources are positioned opposite the two high-speed cameras 34 for illumination. Data acquired by the high-speed cameras 34 is transmitted to the image processing platform 32 outside the vacuum chamber 35. The data lines of the high-speed cameras 34 are connected to the image processing platform 32 via the camera circuit through-chamber flange 33. The high-speed cameras 34 use FlowSense EO 6M-25 cameras and are located inside the camera vacuum protective housing. The image processing platform 32 is connected to the laser 30 via a synchronizer 31.

[0044] The sampling pipeline 24 employs segmented measurement. When measuring a specific segment, the PIV flow velocity measurement system and high-speed imaging system are correspondingly positioned on the outside of that segment. In this implementation, each pipe segment to be measured has two measurement points, i.e., the measurement area, and the measurement area section uses quartz glass.

[0045] The signal acquisition system is used to simultaneously measure the gas pressure at all measuring points in the test section of the sample delivery pipe 24 and to monitor the vacuum level inside the vacuum chamber 35 in real time; pressure sensors and vacuum gauges are used. Pressure sensors are installed at key locations in the starting, middle, and ending sections of the sample delivery pipe 24 to measure the pipe wall pressure.

[0046] like Figure 3 As shown, a full-size sample delivery pipe model was used to measure the gas flow field characteristics. The sample delivery pipe 24 was divided into three sections: I, II, and III. Twelve static pressure measuring points, P1 to P12, were set outside the sample delivery pipe 24 to measure the static pressure of the gas inside the pipe; that is, pressure sensors were installed at the static pressure measuring points. Three regions, A, B, and E, were set up to measure the flow velocity inside the pipe. Two experiments were required for each operating condition: one simultaneously measuring regions A and B, and the other measuring region E. The gas path system remained consistent between the two experiments, except for the difference in the PIV measurement location (i.e., which region was measured outside the pipe section in that region).

[0047] like Figure 4 As shown, during the measurement of the full-link particle motion characteristics under gas excitation, data comparison was used to confirm that the experimental conditions were consistent with those of the flow field characteristic measurement experiment. Three regions, S1, S2, and S3, were set up, and a high-speed camera 34 was used to measure the particle characteristics inside the pipe. Except for the tracer particle generator 11, which contained no tracer particles, the gas path system and... Figure 1 The above should be consistent with the previous one.

[0048] The control system 37 is used to control the operating sequence of the gas supply system, purging system, PIV flow rate measurement system, and high-speed photography system. The control system 37 is located outside the vacuum chamber 35 and is electrically connected to the inside of the chamber via a cable through the chamber flange 36.

[0049] Vacuum chamber 35 simulates the vacuum environment of the target small celestial body, mainly reflected in the initial vacuum level P0 and dynamic vacuum level P during the experiment. A Based on the numerical simulation and experimental results of gas-solid coupling from small celestial body gas sampling, when the dynamic vacuum degree is greater than 2.5 × 10⁻⁶, -1 The gas nozzle flow field can only be consistent with that under absolute vacuum conditions at pressure P. The dynamic vacuum level in the vacuum experiment depends on the size of the vacuum chamber volume (35%); the larger the volume, the less sensitive the vacuum level is to the sample gas flow rate. During gas blowing sampling, assume the sample gas flow rate is Q (L / min) and the gas pressure is P. g (MPa), the dynamic vacuum level of the environment after gas excitation is P A(Pa / s), the volume of the vacuum chamber is A (m³). 3 The calculation method for ) is shown in equation (1):

[0050]

[0051] To ensure that the acceleration of the simulated star soil particles under the influence of gas in the ground experiment is consistent with the acceleration under microgravity, it is necessary to select a material with appropriate density to prepare the simulated star soil particles. The actual sampling process is a vacuum microgravity environment, so it can be assumed that the star soil particles are only affected by the airflow. In addition to the airflow, the influence of gravity on the simulated star soil particles in the ground-based vacuum experiment cannot be ignored. According to Newton's second law, when the acceleration of a single simulated star soil particle is the same in the actual sampling process and the ground experiment, the following relationship (2) is satisfied:

[0052]

[0053] Where F represents the aerodynamic force on the particle in the airflow, m is the mass of a single simulated stellar soil particle in the ground test, and m0 is the mass of a simulated stellar soil particle of the same volume with the same density as the in-orbit stellar soil. The particle density ρ in the ground simulation test can be obtained through substitution. p As shown in equation (3). In the actual experiment, collisions between particles and collisions between particles and the wall are considered. d is the particle size of the simulated star soil particles, which is generally taken as 1-20 mm. In the experiment, ρ p The value should be less than the theoretically calculated value.

[0054]

[0055] This experiment simulates the high-vacuum environment of a small celestial body using a large vacuum chamber. The experiment was conducted within the vacuum chamber at 35°C to verify the effect of different back pressures on gas-blown sampling and transfer, and to record experimental data. The experimental procedure is as follows: Figure 5 As shown, it includes the following steps:

[0056] a. Pre-experiment equipment status check. This includes checking the airtightness of the sample delivery pipe 24; checking the effectiveness of the flow meter, pressure sensor, and solenoid valve; checking the relative position of the nozzle and sample delivery pipe 24; and checking the relative position of the high-speed camera 34, LED light source, and the test area of ​​the pipe section.

[0057] b. Connect the signal acquisition cable, connect the measurement circuit, check the continuity with a multimeter, and connect the acquisition instrument to check the correctness of the signal under no-load conditions.

[0058] c. Based on the timing requirements of the air supply system, pressure sensor, PIV flow velocity measurement system or high-speed photography system, and signal acquisition system, complete the timing control settings for control system 37. First, conduct flow field characteristic experiments for verification, and then conduct particulate matter characteristic experiments for verification.

[0059] d. Conduct the experiment under standard atmospheric pressure according to the experimental procedure to verify the effectiveness of the differential pressure transmitter 23 and high-speed camera 34 in measuring the sample flow field during the experiment.

[0060] e. Conduct a vacuum chamber closure inspection at 35°C. After the inspection is passed, start the vacuum pumping system to evacuate the chamber until a certain required vacuum level is achieved. If the vacuum level is not met, continue evacuating the chamber.

[0061] f. Conduct the experiment according to the experimental procedures, division of labor, and command list, and record the experimental parameters and results using the data recording table. If any abnormalities occur in the vacuum environment or gas supply parameters during the experiment, troubleshooting and resolving the problem are required before re-implementing the experiment under the same conditions, returning to the vacuuming step.

[0062] g. Store electronic data.

[0063] h. End the experiment and open the chamber to prepare for the next stage of the experiment.

[0064] In summary, the above are merely preferred embodiments of the present invention and are 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 within the scope of protection of the present invention.

Claims

1. A vacuum experimental verification system for small celestial body excitation sampling and gas-blown sample delivery, characterized in that, It includes a vacuum chamber, sample delivery pipeline, gas supply system I, gas supply system II, tracer particle generator, control system, PIV flow rate measurement system, high-speed photography system, and signal acquisition system; The gas supply system I is connected in series with the tracer particle generator. The gas supply ports of the gas supply system I are located at the inlet and middle of the sample delivery pipe, used to provide tracer particles and excite simulated stellar soil particles. The gas supply ports of the gas supply system II are located at the beginning and middle sections of the sample delivery pipe, used to blow away tracer particles adhering to the inner wall of the pipe. The sample delivery pipe and the tracer particle generator are both located inside the vacuum chamber. The PIV velocity measurement system is located outside the section of the sample delivery pipe to be tested, and performs flow field characteristic experiments by measuring the flow velocity of the tracer particles inside the sample delivery pipe. The high-speed photography system is located outside the section of the sample delivery pipe to be tested, and performs particulate matter characteristic experiments by measuring the flow velocity of simulated stellar soil particles. The signal acquisition system is used to simultaneously measure the gas pressure at all measuring points of the section of the sample delivery pipe to be tested and to monitor the vacuum level inside the vacuum chamber in real time. The control system is used to control the working sequence of the gas supply system, the blowing system, the PIV velocity measurement system, and the high-speed photography system. The density of the simulated spherical soil particles was determined when the actual sampling process and the acceleration of a single particle were the same as those in the ground test. satisfy F To simulate the aerodynamic forces experienced by spherical particles in airflow, m For the mass of a single particle in ground testing, m 0 represents the mass of particles of the same volume with the density of orbital regolith. d To simulate the particle size of star soil.

2. The small celestial body excitation sampling and gas-blown sample delivery vacuum experimental verification system as described in claim 1, characterized in that, The volume of the vacuum chamber A The calculation formula is as follows: Q For the sample gas flow rate, P g The gas pressure is [value], and the dynamic vacuum level of the environment after gas excitation is [value]. P A , P A Greater than 2.5 × 10 -1 Pa 。 3. The vacuum experimental verification system for small celestial body excitation sampling and gas blowing sample delivery as described in claim 1, characterized in that, The gas supply system I includes a nitrogen buffer tank, a pressure reducing valve, a flow meter, a solenoid valve, a trans-chamber flange, a pressure sensor, a sampling nozzle, a sample delivery nozzle, and pipelines; A nitrogen buffer tank is supplied with nitrogen via a pipeline that extends into the vacuum chamber through a trans-chamber flange and is connected in series with a tracer particle generator. The trans-chamber flange is mounted on the vacuum chamber. The tracer particle generator is connected to a sampling nozzle and a delivery nozzle via pipelines. The sampling nozzle is located at the inlet of the delivery pipe, and the delivery nozzle is located in the middle of the delivery pipe. The pressure reducing valve and flow meter are installed on the pipeline between the nitrogen buffer tank and the trans-chamber flange. Solenoid valves are installed on the pipelines before and after the tracer particle generator and before the sampling nozzle. The pressure sensor is installed on the pipeline at the inlet of the delivery pipe to ensure the inlet pressure.

4. The vacuum experimental verification system for small celestial body excitation sampling and gas blowing sample delivery as described in any one of claims 1-3, characterized in that, The PIV flow velocity measurement system includes a laser, an in-cabin light guide arm, an external light guide arm, a transmission and reflection mirror assembly, a quartz glass flange, and a sheet light module. Both the internal and external light guide arms are equipped with transmission and reflection mirror groups. The laser and the external light guide arm are located outside the vacuum chamber, while the internal light guide arm is located inside the vacuum chamber. The quartz glass flange is fixed to the vacuum chamber. The laser beam emitted by the laser is reflected sequentially by the external and internal light guide arms and then focused onto the sheet light module. The sheet light module then splits and reflects the beam to the two test areas of the sample delivery pipe section.

5. The vacuum experimental verification system for small celestial body excitation sampling and gas blowing sample delivery as described in claim 4, characterized in that, The high-speed photography system includes an image processing platform, two high-speed cameras and matching LED light sources. The two high-speed cameras are located inside the vacuum chamber, corresponding to two test areas of the sample delivery pipe section to be tested. The data collected by the high-speed cameras is transmitted to the image processing platform outside the vacuum chamber. The image processing platform is connected to the laser through a synchronizer.

6. The vacuum experimental verification system for small celestial body excitation sampling and gas blowing sample delivery as described in claim 5, characterized in that, The test section of the sample delivery pipe is made of quartz glass.

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