System and method for testing vacuum thermally-induced sublimation loss rate of ice-containing soil

Abstract

The invention discloses a system and a method for testing the vacuum thermal sublimation loss rate of ice-containing soil, and belongs to the technical field of vacuum thermal sublimation simulation experiments of space exploration. The test system comprises a data acquisition system, a sample preparation chamber, a first vacuum low-temperature chamber, a second vacuum chamber and an in-place detection simulation vacuum chamber, and can timely place a prepared sample in a test condition, so that the prepared sample is prevented from changing in advance when not entering the simulation vacuum chamber; therefore, the initial condition of the sample is effectively controlled, the accuracy and repeatability of measured data are ensured, meanwhile, the change process of the monitored sample from the initial state to the target condition can be implemented, and in-situ measurement is realized. The test method comprises the influence of factors such as heating temperature, star soil heap type, sample throwing, sample physical property parameters and the like on the vacuum thermally-induced sublimation loss rate of the ice-containing star soil, provides correction parameters for the real water content of the original star soil, and also provides data support for improving the extraction efficiency of lunar soil water ice.

Description

Technical Field

[0001] The present invention relates to the technical field of vacuum thermal sublimation simulation experiments for space exploration, and particularly relates to a test system and a test method for the vacuum thermal sublimation loss rate of ice-containing planetary soil, which are applicable to the detection and analysis of water-containing substances on the surfaces of celestial bodies such as the moon and Mars. Background Art

[0002] With the advancement of deep space exploration missions, the research on water-containing substances on the surfaces of celestial bodies such as the moon and Mars has become an important topic. In order to detect the water ice resources in the polar regions of the moon, Mars, etc., mechanical devices are required to dig ice-containing planetary soil on the celestial body surface and transport it to a water detection instrument for analysis. However, during the digging process, the friction between the mechanical device and the planetary soil will cause the temperature of the planetary soil to rise, and the high vacuum environment on the planet surface makes it difficult for the heat to dissipate quickly, resulting in sublimation loss of the ice-containing planetary soil during transportation due to temperature rise. Therefore, in order to obtain the loss amount of water molecules in the planetary soil during the collection process and provide correction parameters for obtaining the true water content in the original planetary soil, simulation experiments need to be carried out to measure the vacuum thermal sublimation loss rate of the planetary soil.

[0003] The prior art provides an in-situ measurement experiment method for the water sublimation loss rate of water-containing simulated lunar soil. This method is to pre-place test samples such as simulated lunar soil in a vacuum system, and then carry out cooling and vacuum pumping operations, and obtain the influence of different low temperature zones, vacuum degrees, water contents, and compactness factors on the water sublimation rate of the water-containing lunar soil during the cooling and vacuum pumping processes. However, this method has the following disadvantages: (1) Data distortion problem: The simulated lunar soil is placed in the vacuum system before the test conditions (low temperature, vacuum and other target conditions) are reached, resulting in the sublimation of water in the lunar soil possibly starting before the test conditions are fully met. This will make the measurement data unable to accurately reflect the water sublimation rate under specific low temperature, vacuum degree, water content and compactness conditions, resulting in data distortion.

[0004] (2) Inability to precisely control the initial conditions: Since the simulated lunar soil is placed before the test conditions are reached, the initial water content, compactness and other conditions may change due to premature sublimation, affecting the accuracy and repeatability of the test results.

[0005] (3) Lack of real-time in the test process: This method cannot achieve true "in-situ" measurement because the simulated lunar soil has been exposed to a non-target environment before the test conditions are reached, and the change process from the initial state to the target conditions cannot be monitored in real time.

[0006] (4) Limited scope of application: This method may only be applicable to the research of simulated lunar soil under specific conditions and is difficult to be extended to more complex environments.

[0007] Therefore, to solve the above problems, the present invention provides a test system and a test method for the vacuum thermosublimation loss rate of ice-containing lunar soil, so as to provide accurate correction parameters for obtaining the true water content in the original lunar soil. Summary of the Invention

[0008] To solve the problems raised in the above background art, the main object of the present invention is to provide a test system and a test method for the vacuum thermosublimation loss rate of ice-containing lunar soil with high precision and controllable multiple parameters, so as to provide accurate correction parameters for obtaining the true water content in the original lunar soil and provide a reliable solution for the assessment and utilization of water resources in deep space exploration.

[0009] To achieve the above object, the present invention provides a test system for the vacuum thermosublimation loss rate of ice-containing lunar soil, including a data acquisition system and a sample preparation chamber, a first vacuum cryogenic chamber, a second vacuum chamber, and an in-situ detection simulation vacuum chamber connected in sequence; The sample preparation chamber is used to make a dry lunar soil of the original lunar soil into an ice-containing lunar soil sample; The first vacuum cryogenic chamber is used to control the ice-containing lunar soil sample to be maintained in a vacuum cryogenic environment to prevent sample loss; The second vacuum chamber is used to transfer the ice-containing lunar soil sample stored in the first vacuum cryogenic chamber to the in-situ detection simulation vacuum chamber; The in-situ detection simulation vacuum chamber includes a vacuum tank, a cold plate is arranged in the vacuum tank, and a robotic arm, a balance system, and a heating device are arranged on the cold plate; the balance system includes a balance temperature control system and a sample receiving unit, and is used to weigh and test the vacuum thermosublimation loss rate of the ice-containing lunar soil sample; The data acquisition system records the test data of the vacuum thermosublimation loss rate of the ice-containing lunar soil in real time.

[0010] Further, the balance temperature control system includes a sample support, a radiation shield, a first semiconductor refrigeration chip, a balance upper cover, a balance, a balance lower cover, a second semiconductor refrigeration chip, a balance support, and a balance base arranged in sequence from top to bottom. The radiation shield covers the balance. Covers are arranged around the balance, and a third semiconductor refrigeration chip is arranged on the outside of the cover. The sample support is embedded on the radiation shield, one end of which is connected to the balance, and the other end is connected to the sample receiving unit.

[0011] Further, there are multiple balance systems, including a first balance system, a second balance system, and a third balance system. The first balance system, the second balance system, and the third balance system adopt the same structure of the balance temperature control system and different structures of the sample receiving unit. By setting multiple balance systems in the present invention, the vacuum thermosublimation loss rate of ice-containing lunar soil under the influence of different factors can be tested simultaneously.

[0012] Further, the sample receiving unit of the first weighing system includes a sample cup and a sample cup holder, and the sample cup holder is used to fix the sample cup. The first weighing system provided in the present invention is used to weigh and test the vacuum thermosublimation loss rate of ice-containing lunar soil at different heating temperatures. By using the sample cup to hold the sample, and then placing the sample cup containing the sample on the heating device for heating, the influence of the heating temperature on the vacuum thermosublimation loss rate of ice-containing lunar soil is tested.

[0013] Further, the sample receiving unit of the second weighing system includes a tray, an infrared sensor bracket and an infrared sensor. The infrared sensor bracket is used to adjust and fix the position of the infrared sensor so that the infrared sensor can measure the sample temperature on the tray in real time. The second weighing system provided in the present invention is used to weigh and test the vacuum thermosublimation loss rate of ice-containing lunar soil in the state of throwing and sending samples. By using the large area of the tray, the scattered samples can be completely received.

[0014] Further, the sample receiving unit of the third weighing system includes a funnel, a funnel bracket, a lunar soil holder, a tray, an infrared sensor and an infrared sensor bracket; the funnel is arranged on the funnel bracket and is used to locate the position of the lunar soil holder, and the lunar soil holder is arranged above the tray and is used to shape the pile of ice-containing lunar soil samples. The third weighing system provided in the present invention is used to weigh and test the vacuum thermosublimation loss rate of ice-containing lunar soil under different sample pile shapes.

[0015] Further, the first vacuum cryogenic chamber includes a liquid nitrogen cold finger, a first gate valve, a first vacuum system and a primary vacuum transition chamber; The first gate valve is arranged on the transfer channel between the sample preparation chamber and the first vacuum cryogenic chamber, and the first vacuum system and the liquid nitrogen cold finger are used to vacuum freeze the ice-containing lunar soil samples in the primary vacuum transition chamber.

[0016] Further, the second vacuum chamber includes a first mechanical gripper, a second mechanical gripper, a second gate valve, a third gate valve, a second vacuum system and a secondary vacuum transition chamber; The second gate valve is arranged on the transfer channel between the first vacuum cryogenic chamber and the second vacuum chamber, and the first mechanical gripper is used to transport the ice-containing lunar soil samples from the first vacuum cryogenic chamber to the second vacuum chamber; The third gate valve is arranged on the transfer channel between the second vacuum chamber and the in-situ detection simulation vacuum chamber, and the second mechanical gripper is used to transport the ice-containing lunar soil samples from the second vacuum chamber to the in-situ detection simulation vacuum chamber.

[0017] Further, the sample preparation chamber is an anhydrous and low-oxygen glove box, which includes a weighing module, a drying module, a cryogenic freezing and stirring module, a temperature-controlled evaporation module and a preparation container.

[0018] On the other hand, the present invention provides a method for testing the vacuum thermosublimation loss rate of ice-containing planetary soil by using the aforementioned testing system for the vacuum thermosublimation loss rate of ice-containing planetary soil, including the following steps: Perform parameter initialization settings on the testing system for the vacuum thermosublimation loss rate of ice-containing planetary soil; Calibrate the stability of the balance system in the in-situ detection simulation vacuum chamber; Make a series of ice-containing planetary soil samples with different physical property parameters from the dry soil of the original planetary soil in the sample preparation chamber; transfer the ice-containing planetary soil samples from the sample preparation chamber to the first vacuum low-temperature chamber for vacuum freezing; After transferring the vacuum-frozen ice-containing planetary soil samples to the second vacuum chamber, reduce the vacuum degree of the second vacuum chamber, and then transfer the ice-containing planetary soil samples from the second vacuum chamber to the in-situ detection simulation vacuum chamber; After transferring the ice-containing planetary soil samples into the in-situ detection simulation vacuum chamber, conduct a sublimation test, measure the weight change of the ice-containing planetary soil samples before and after sublimation, and obtain the vacuum thermosublimation loss rate of the ice-containing planetary soil samples.

[0019] Further, the physical property parameters include moisture content, particle size, density, and particle size distribution, but it should be understood that the physical property parameters can be increased or decreased according to actual test needs.

[0020] Further, the sublimation test includes testing the vacuum thermosublimation loss rate of ice-containing planetary soil samples at different heating temperatures, including the following steps: Step S11, place the transferred ice-containing planetary soil sample on the balance system to measure the initial mass of the sample , Step S12, transfer the ice-containing planetary soil sample to a heating device at a preset temperature for heating, and take out the ice-containing planetary soil sample from the heating device every interval, place it on the balance system to measure the mass of the ice-containing planetary soil sample at this time , then put the ice-containing planetary soil sample back into the heating device for heating, and calculate the moisture sublimation rate of the ice-containing planetary soil in each time period and the moisture sublimation rate per unit mass of the ice-containing planetary soil ; Step S13, until the finally measured moisture sublimation rate of the ice-containing planetary soil is less than the drift amount during the balance calibration, that is, it is considered that all the moisture in the ice-containing planetary soil sample has sublimated. At this time, the moisture sublimation rate per unit mass of the ice-containing planetary soil measured is the vacuum thermosublimation loss rate of the ice-containing planetary soil sample; Step S14, sequentially adjust the preset temperature set by the heating device, and repeat the above steps S11 to S13 to obtain the vacuum thermosublimation loss rate of the ice-containing planetary soil samples at different heating temperatures.

[0021] Further, after step S14, the following steps are further included: replacing the ice-containing lunar soil sample, sequentially changing the physical property parameters of the ice-containing lunar soil sample, and repeating the above steps S11 to S14 to obtain the vacuum thermosublimation loss rate of the ice-containing lunar soil sample under the influence of different heating temperatures and different sample physical property parameters.

[0022] By testing the vacuum thermosublimation loss rate of the ice-containing lunar soil sample under the influence of different heating temperatures and different sample physical property parameters, the heating extraction efficiency of the ice-containing lunar soil sample under the influence of different sample physical property parameters at different temperatures can be obtained, providing a theoretical reference for the subsequent rapid extraction of water in the lunar soil.

[0023] Further, the sublimation test includes testing the vacuum thermosublimation loss rate of the ice-containing lunar soil sample in a sprinkled state, including the following steps: Step S21, pouring the transferred ice-containing lunar soil sample onto the balance system in a natural sprinkling manner to measure the initial mass of the sample ; Step S22, leaving the ice-containing lunar soil sample stationary in the balance system and measuring the mass of the ice-containing lunar soil sample at intervals of interval, calculating the water sublimation rate of the ice-containing lunar soil in each time period and the water sublimation rate per unit mass of the ice-containing lunar soil ; ; Step S23 until the finally measured water sublimation rate of the ice-containing lunar soil is less than the drift amount during the balance calibration, that is, it is considered that all the water in the ice-containing lunar soil sample has sublimated. At this time, the water sublimation rate per unit mass of the ice-containing lunar soil measured is the vacuum thermosublimation loss rate of the ice-containing lunar soil sample; Step S24, adjusting the temperature control temperature of the balance system, replacing the ice-containing lunar soil sample with different physical property parameters, and repeating the above steps S21 to S23 to obtain the vacuum thermosublimation loss rate of the ice-containing lunar soil in the sprinkled sample state under different temperature conditions and different physical property parameters.

[0024] Further, the sublimation test includes testing the vacuum thermosublimation loss rate of the ice-containing lunar soil sample under different stacking patterns, including the following steps: Step S31, pouring the transferred ice-containing lunar soil sample into the lunar soil tray of the balance system to measure the initial mass of the ice-containing lunar soil sample ; Step S32, leaving the ice-containing lunar soil sample stationary in the balance system and measuring the mass of the ice-containing lunar soil sample at intervals of interval, calculating the water sublimation rate of the ice-containing lunar soil in each time period ; and the sublimation rate of water per unit mass of ice-containing lunar soil ; Step S33 until the finally measured sublimation rate of water in the ice-containing lunar soil is less than the drift amount during the balance calibration, that is, it is considered that all the water in the ice-containing lunar soil sample has sublimated. At this time, the sublimation rate of water per unit mass of the ice-containing lunar soil is the vacuum thermally induced sublimation loss rate of the ice-containing lunar soil sample; Step S34, change the shape of the lunar soil holder, and repeat the above steps S31 to S33 to obtain the vacuum thermally induced sublimation loss rates of the ice-containing lunar soil samples under different stacking patterns.

[0025] Furthermore, after step S34, the following steps are further included: adjust the temperature of the balance system, replace the ice-containing lunar soil sample, sequentially change the physical property parameters of the ice-containing lunar soil sample, and repeat the above steps S31 to S34 to obtain the vacuum thermally induced sublimation loss rates of the ice-containing lunar soil samples under the influence of different sample physical property parameters.

[0026] Among them, the sublimation rate of water in the ice-containing lunar soil and the sublimation rate of water per unit mass of the ice-containing lunar soil in each time period of the above test process are calculated by the following formulas respectively: (1); (2); In formulas (1) and (2), is the sublimation rate of water in the ice-containing lunar soil, is the sublimation rate of water per unit mass of the ice-containing lunar soil, is the initial mass of the ice-containing lunar soil sample, is the mass of the ice-containing lunar soil sample after each interval change, is the time interval.

[0027] Compared with the prior art, the present invention has the following beneficial effects: (1) The test system for the vacuum thermally induced sublimation loss rate of the ice-containing lunar soil provided by the present invention can timely place the prepared sample in the test conditions by setting up a sample preparation chamber, a first vacuum low-temperature chamber, a second vacuum chamber and an in-situ detection simulation vacuum chamber. The first vacuum low-temperature chamber and the second vacuum chamber are used to transfer the sample to the in-situ detection simulation vacuum chamber in a vacuum and freezing environment, avoiding the premature change of the prepared sample before entering the simulation vacuum chamber, thus effectively controlling the initial conditions of the sample, ensuring the accuracy and repeatability of the measurement data, and avoiding the distortion of the test data; the set in-situ detection simulation vacuum chamber simulates the vacuum low-temperature environment where the lunar soil is located and is used for the test of the vacuum thermally induced sublimation loss rate. At the same time, the set data processing system can monitor the change process of the sample from the initial state to the target conditions in real time and realize in-situ measurement.

[0028] (2) If a base is to be established in the water-containing area of the moon in the future, extracting water resources from lunar soil will be the most convenient way. The extraction efficiency of water ice in lunar soil is related to factors such as heating temperature, heating duration, the binding characteristics of water ice and soil, the density of water ice and soil, and the lunar soil pile type. Therefore, it is necessary to consider the influence of relevant factors on the extraction efficiency of water ice in lunar soil. The test method for the vacuum thermosublimation loss rate of ice-containing planetary soil provided by the present invention includes the test of the extraction efficiency of water ice in lunar soil, that is, the vacuum thermosublimation loss rate of ice-containing planetary soil samples at different heating temperatures in the test method. At the same time, the influence of multiple factors such as environmental temperature, planetary soil pile type, throwing and feeding actions, and sample physical property parameters such as moisture content, particle size, density, and particle size on the vacuum thermosublimation loss rate of ice-containing planetary soil is also tested, providing correction parameters for the true water content of the original planetary soil and also providing data support for improving the extraction efficiency of water ice in lunar soil. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 FIG. shows the overall structural schematic diagram of the test system for the vacuum thermosublimation loss rate of ice-containing planetary soil according to an embodiment of the present invention; Figure 2 FIG. shows the structural schematic diagram of the in-situ detection simulation vacuum chamber according to an embodiment of the present invention, where Figure 2 2(a) in FIG. is the external structural schematic diagram of the in-situ detection simulation vacuum chamber; Figure 2 2(b) in FIG. is the internal structural schematic diagram of the in-situ detection simulation vacuum chamber; Figure 3 FIG. shows the structural schematic diagram of the first balance system according to an embodiment of the present invention, where Figure 3 3(a) in FIG. is the external structural schematic diagram of the first balance system, Figure 3 3(b) in FIG. is the internal structural schematic diagram of the first balance system; Figure 4 FIG. shows the structural schematic diagram of the heating device according to an embodiment of the present invention; where Figure 4 4(a) in FIG. is the side view of the heating device, Figure 4 4(b) in FIG. is the front view of the heating device; Figure 5 FIG. shows the structural schematic diagram of the second balance system according to an embodiment of the present invention, where Figure 5 5(a) in FIG. is the structural schematic diagram of the second balance system in the working state, Figure 5 5(b) in FIG. is the structural schematic diagram of the second balance system in the non-working state; Figure 6 FIG. shows the structural schematic diagram of the third balance system according to an embodiment of the present invention, where Figure 6 6(a) in FIG. is the structural schematic diagram of the third balance system in the working state, Figure 6 6(b) in FIG. is the structural schematic diagram of the third balance system in the non-working state; Figure 7 The structural schematic diagrams of two kinds of lunar soil trays according to the embodiments of the present invention are shown; Figure 8 A partial structural schematic diagram of a test system for the vacuum thermosublimation loss rate of ice-containing lunar soil according to the embodiments of the present invention is shown; Figure 9 Another partial structural schematic diagram of a test system for the vacuum thermosublimation loss rate of ice-containing lunar soil according to the embodiments of the present invention is shown; Figure 10 The flow schematic diagram of a test method for the vacuum thermosublimation loss rate of ice-containing lunar soil according to the embodiments of the present invention is shown.

[0030] Among them, the above-mentioned drawings include the following reference numerals: 1. Sample preparation chamber, 2. First vacuum low-temperature chamber, 3. Second vacuum chamber, 4. In-place detection simulation vacuum chamber, 5. Data acquisition system, 11. Weighing module, 12. Drying module, 13. Low-temperature freezing and stirring module, 14. Temperature-controlled evaporation module, 15. Preparation container, 21. Liquid nitrogen cold finger, 22. First gate valve, 23. First vacuum system, 24. Primary vacuum transition chamber, 31. First mechanical gripper, 32. Second mechanical gripper, 33. Second gate valve, 34. Third gate valve, 35. Second vacuum system, 36. Secondary vacuum transition chamber, 41. Vacuum tank, 42. Cold plate, 43. Manipulator, 44. Heating device, 45. First balance system, 46. Second balance system, 47. Third balance system, 411. Sample support, 412. Radiation shield, 413. First semiconductor refrigeration chip, 414. Balance upper cover, 415. Balance, 416. Balance lower cover, 417. Second semiconductor refrigeration chip, 418. Balance support, 419. Balance base, 420. Cover plate, 421. Third semiconductor refrigeration chip, 441. Heating coil, 451. Sample cup, 452. Sample cup holder, 461. Tray, 462. Infrared sensor bracket, 463. Infrared sensor, 471. Funnel, 472. Funnel bracket, 473. Lunar soil tray. Detailed implementation manners

[0031] It should be noted that the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. The purpose of providing these embodiments is to make the disclosure of the present invention more thorough and comprehensive. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0032] The vacuum thermosublimation loss rate refers to the proportion of mass reduction of a substance due to sublimation caused by heating in a vacuum environment. The test method for the vacuum thermosublimation loss rate of ice-containing lunar soil in the present invention is the proportion of the reduction in the amount of ice-containing lunar soil due to the sublimation of water caused by heating the ice-containing lunar soil in a vacuum environment. The mass measurement accuracy in the test system for the vacuum thermosublimation loss rate of ice-containing lunar soil in the present invention is ±1 mg, the temperature uniformity is ±0.1 K, and the calibration error of the measured vacuum thermosublimation loss rate of ice-containing lunar soil is ≤5%.

[0033] To achieve the above object, the first aspect of the embodiment of the present invention provides a test system for the vacuum thermosublimation loss rate of ice-containing lunar soil, as Figure 1 and Figure 2 shown, which includes a sample preparation chamber 1, a first vacuum low-temperature chamber 2, a second vacuum chamber 3, an in-situ detection simulation vacuum chamber 4 connected in sequence, and a data acquisition system 5. The sample preparation chamber 1 is used to make a dry soil of the original lunar soil into an ice-containing lunar soil sample. The first vacuum low-temperature chamber 2 is used to control the ice-containing lunar soil sample to be maintained in a vacuum low-temperature environment to prevent sample loss. The second vacuum chamber 3 is used to transfer the ice-containing lunar soil sample stored in the first vacuum low-temperature chamber 2 to the in-situ detection simulation vacuum chamber 4. The in-situ detection simulation vacuum chamber 4 is used to simulate the vacuum low-temperature environment where the ice-containing lunar soil is located, and its temperature is controllable. It includes a vacuum tank 41, a cold plate 42 is arranged in the vacuum tank 41, the temperature in the vacuum tank 41 is adjusted, and a robotic arm 43, a balance system, and a heating device 44 are arranged on the cold plate 42. The balance system includes a balance temperature control system and a sample receiving unit, and is used to weigh and test the vacuum thermosublimation loss rate of the ice-containing lunar soil sample. The data acquisition system 5 records the test data of the vacuum thermosublimation loss rate of the ice-containing lunar soil in real time.

[0034] In a specific embodiment of the present invention, as Figure 1 shown, there are multiple balance systems, including a first balance system 45, a second balance system 46, and a third balance system 47. The first balance system 45 is used to weigh and test the vacuum thermosublimation loss rate of the ice-containing lunar soil at different heating temperatures. The second balance system 46 is used to weigh and test the vacuum thermosublimation loss rate of the ice-containing lunar soil in the state of throwing and sending samples. The third balance system 47 is used to weigh and test the vacuum thermosublimation loss rate of the ice-containing lunar soil under different sample stacking patterns.

[0035] In a specific embodiment of the present invention, the first balance system 45, the second balance system 46, and the third balance system 47 adopt balance temperature control systems with the same structure and sample receiving units with different structures, as Figure 3As shown in the figure, the balance temperature control system includes a sample support 411, a radiation shield 412, a first semiconductor refrigeration chip 413, a balance upper cover 414, a balance 415, a balance lower cover 416, a second semiconductor refrigeration chip 417, a balance support 418, and a balance base 419, which are arranged in sequence from top to bottom. The radiation shield 412 covers the balance 415. Covers 420 are arranged around the balance 415, and a third semiconductor refrigeration chip 421 is arranged on the outer side of the cover 420. The sample support 411 is embedded in the radiation shield 412, one end of which is connected to the balance 415, and the other end is connected to the sample receiving unit.

[0036] In the present invention, semiconductor refrigeration chips are arranged around the balance. The semiconductor refrigeration chips can both refrigerate and heat. By changing the polarity of the direct current, refrigeration or heating can be achieved on the same refrigeration chip, so as to control the temperature of the balance and be used to test the vacuum thermosublimation loss rate of the ice-containing lunar soil samples under different temperature conditions. The covers arranged around the balance of the present invention, as well as the balance upper cover and the balance lower cover, can be used for heat preservation and isolation from external influences to ensure the stability of the balance reading. Further, a thermal insulation multi-layer is coated on the outside of the balance temperature control system, such as coating on the outer periphery of the cover, and the third semiconductor refrigeration chip is arranged inside the thermal insulation multi-layer to better control the temperature of the balance.

[0037] In a specific embodiment of the present invention, as Figure 3 and Figure 4 shown, the sample receiving unit of the first balance system 45 includes a sample cup 451 and a sample cup holder 452. The sample cup holder 452 is used to fix the sample cup 451. The heating device 44 includes a heating coil 441, and the sample cup 451 is placed inside the heating coil 441 for heating.

[0038] In a specific embodiment of the present invention, as Figure 5 shown, the sample receiving unit of the second balance system 46 includes a tray 461, an infrared sensor bracket 462, and an infrared sensor 463. The infrared sensor bracket 462 is used to adjust and fix the position of the infrared sensor 463 so that the infrared sensor 463 can measure the sample temperature of the tray 461 in real time.

[0039] In a specific embodiment of the present invention, as Figure 6 and Figure 7 shown, the sample receiving unit of the third balance system 47 includes a funnel 471, a funnel bracket 472, a lunar soil support 473, a tray 461, an infrared sensor, and an infrared sensor bracket; the funnel 471 is arranged on the funnel bracket 472 and is used to position the lunar soil support 473. The lunar soil support 473 is arranged above the tray 461. The lunar soil support 473 is woven with a metal mesh, and its structure can be selected as conical, cylindrical, etc. to shape the pile of the sample.

[0040] In a specific embodiment of the present invention, as Figure 8 and Figure 9 shown, the first vacuum cryogenic chamber 2 includes a liquid nitrogen cold finger 21, a first gate valve 22, a first vacuum system 23 and a primary vacuum transition chamber 24; the first gate valve 22 is arranged on the transfer channel between the sample preparation chamber 1 and the first vacuum cryogenic chamber 2, and the first vacuum system 23 and the liquid nitrogen cold finger 21 are used for vacuum freezing the ice-containing lunar regolith sample in the primary vacuum transition chamber 24.

[0041] In a specific embodiment of the present invention, as Figure 8 and Figure 9 shown, the second vacuum chamber 3 includes a first mechanical gripper 31, a second mechanical gripper 32, a second gate valve 33, a third gate valve 34, a second vacuum system 35 and a secondary vacuum transition chamber 36; the second gate valve 33 is arranged on the transfer channel between the first vacuum cryogenic chamber 2 and the second vacuum chamber 3, and the first mechanical gripper 31 is used for transporting the ice-containing lunar regolith sample from the first vacuum cryogenic chamber 2 into the second vacuum chamber 3; the third gate valve 34 is arranged on the transfer channel between the second vacuum chamber 3 and the in-situ detection simulation vacuum chamber 4, and the second mechanical gripper 32 is used for transporting the ice-containing lunar regolith sample from the second vacuum chamber 3 into the in-situ detection simulation vacuum chamber 4; the second vacuum system 35 is used to achieve a vacuum degree better than 10 -2 Pa in the secondary vacuum transition chamber 36.

[0042] In a specific embodiment of the present invention, as Figure 9 shown, the sample preparation chamber 1 is an anhydrous and low-oxygen glove box, which includes a weighing module 11, a drying module 12, a low-temperature freezing and stirring module 13, a temperature-controlled evaporation module 14, and a preparation container 15.

[0043] In a specific embodiment of the present invention, as Figure 9 shown, the data acquisition system 5 includes a balance system data acquisition system 51. Further preferably, it also includes a temperature acquisition system 52 for acquiring the temperature of the balance system; a particle size data measurement system 53 (such as a laser particle size analyzer), and a moisture content measurement system 54 (such as a Karl Fischer moisture content analyzer).

[0044] In the second aspect of the embodiments of the present invention, there is also provided a method for testing the vacuum thermosublimation loss rate of ice-containing lunar regolith by using the aforementioned test system for the vacuum thermosublimation loss rate of ice-containing lunar regolith. The process is as Figure 10 shown, and includes the following steps: Step S1, parameter initialization: Initialize and set the parameters of the test system for the vacuum thermosublimation loss rate of ice-containing lunar regolith; Step S2, balance system stability calibration: Calibrate the stability of the balance system in the in-situ detection simulation vacuum chamber; Step S3, sample preparation: The dry soil of the original lunar regolith is made into a series of ice-containing lunar regolith samples with different physical property parameters in the sample preparation chamber; the physical property parameters include water content, particle size, density, and particle size distribution. Step S4, sample transfer: Transfer the ice-containing lunar regolith sample from the sample preparation chamber to the first vacuum cryogenic chamber for vacuum freezing; after transferring the vacuum-frozen ice-containing lunar regolith sample to the second vacuum chamber, reduce the vacuum degree of the second vacuum chamber, and then transfer the ice-containing lunar regolith sample from the second vacuum chamber to the in-situ detection simulation vacuum chamber. Step S5, sublimation test: After transferring the ice-containing lunar regolith sample into the in-situ detection simulation vacuum chamber, conduct a sublimation test. Step S6, data processing: Measure the weight change of the ice-containing lunar regolith sample before and after sublimation to obtain the vacuum thermally induced sublimation loss rate of the ice-containing lunar regolith sample.

[0045] In a specific embodiment of the present invention, step S1, parameter initialization includes: (a) Set the in-situ detection simulation vacuum chamber to a specified vacuum degree (the vacuum degree is better than 10 -4 Pa); (b) Set the cold plate to a specified temperature (the temperature stability is within ±2°C); (c) Set the tray temperature of the balance system to a specified temperature (the temperature stability is within ±2°C); (d) Set the balance temperature control system to control the balance to always be within the normal working temperature range (the temperature stability is ±2°C); (e) Set the vacuum degree of the second vacuum chamber to be better than 10 -2 Pa; (f) Set the liquid nitrogen cold finger temperature of the first vacuum cryogenic chamber to ≤ -180°C; (g) Set the water content of the sample preparation chamber to < 1 ppm, and the temperature of the low-temperature stirring system to ≤ -40°C.

[0046] In a specific embodiment of the present invention, step S2, balance system stability calibration includes: (a) Turn on the first balance system, the second balance system, the third balance system, and the balance system data acquisition system; (b) Zero the three balance systems; (c) Place the three balance systems for 1 h; (d) The balance system data acquisition system real-time collects the balance readings; (e) Compare the readings of the three balance systems. When the reading consistency of the three balance systems meets 0.1 mg and the balance system drift is less than 1 mg / h, the balance is considered stable.

[0047] In a specific embodiment of the present invention, step S3, sample preparation includes: (a)Dry the original dry sample of lunar regolith in the drying device of an anhydrous and low-oxygen glove box at 180 - 200 °C for at least 48 hours; (b)After the dried dry sample cools down to 50 - 60 °C, use a weighing module to weigh 100 g of dry soil samples with different particle sizes and pour them into a stainless-steel container. Add distilled water samples to the dry soil samples in small amounts and multiple times to prepare lunar regolith samples with known water contents; (c)Pour the sample in the stainless-steel container into the freezing and stirring module and stir for 10 - 15 minutes; (d)Take out the prepared samples from the freezing and stirring module and sub-pack them into sample bottles, including 1 test sample bottle, 3 calibration sample bottles, and 1 particle size measurement sample bottle; (e)Take out 3 calibration sample bottles and 1 particle size measurement sample bottle, measure the water content of the 3 calibration sample bottles using a Karl Fischer water content measuring instrument, and measure the sample in the particle size measurement sample bottle using a laser particle size analyzer; (f)Using the above method, configure samples with different densities, different water contents, and different particle sizes.

[0048] In a specific embodiment of the present invention, in step S4, transporting the sample includes: (a)Open the first gate valve 22 between the first vacuum cryogenic chamber 2 and the sample preparation chamber 1, transport the empty sample cup to the first vacuum cryogenic chamber 2, then close the first gate valve 22. Press the flange surface of the sample cup against the liquid nitrogen cold finger 21 of the first vacuum cryogenic chamber 2 and pre-freeze it using the liquid nitrogen cold finger 21; (b)After the empty sample cup is pre-frozen, open the first gate valve 22, transport the sample cup to the sample preparation chamber 1, load the configured sample into the sample cup, then transport the sample cup to the first vacuum cryogenic chamber 2 again, close the first gate valve 22, press the flange surface of the sample cup against the liquid nitrogen cold finger 21 of the first vacuum cryogenic chamber 2, and freeze it using the liquid nitrogen cold finger 21. At the same time, turn on the mechanical pump of the first vacuum system 23 of the first vacuum cryogenic chamber. During the freezing of the sample, the mechanical pump of the first vacuum system 23 keeps running until the pressure in the first vacuum cryogenic chamber 2 drops below 20 Pa, and the freezing time meets 8 - 15 minutes; (c)After the sample is frozen for 8 - 15 minutes, open the second gate valve 33 between the second vacuum chamber 3 and the first vacuum cryogenic chamber 2, and use the second mechanical gripper 32 of the second vacuum chamber 3 to transport the sample cup into the second vacuum chamber 3; (d)Close the second gate valve 33, open the third gate valve 34 between the second vacuum chamber 3 and the in-situ detection simulation vacuum chamber 4, and use the first mechanical gripper 31 of the second vacuum chamber 3 to send the sample cup into the in-situ detection simulation vacuum chamber 4; (e) Use the in-place detection to simulate the robotic arm 43 in the vacuum chamber 4 to receive the sample cup and complete the transfer of the ice-containing lunar soil sample.

[0049] In a specific embodiment of the present invention, the sublimation test is to test the vacuum thermally induced sublimation loss rate of the ice-containing lunar soil sample at different heating temperatures, including the following steps: Step S11, use the robotic arm 43 to place the ice-containing lunar soil sample on the first weighing system 45 and measure the initial mass of the ice-containing lunar soil sample ; Step S12, use the robotic arm 43 to transfer the sample cup 451 with the ice-containing lunar soil sample to the heating coil 441 of the heating device 44 for heating (the set heating temperature is, for example, 20°C), and at every interval, use the robotic arm 43 to take out the sample cup 451 from the heating device 44 and place it on the first weighing system 45 for measurement, and measure the mass of the ice-containing lunar soil sample at this time Then, place the sample cup 451 with the ice-containing lunar soil sample back into the heating device for heating, and calculate the moisture sublimation rate of the ice-containing lunar soil in each time period and the moisture sublimation rate per unit mass of the ice-containing lunar soil ; Among them, (1); (2); Step S13, until the finally measured moisture sublimation rate of the ice-containing lunar soil is less than the drift amount during the balance calibration, that is, it is considered that all the moisture in the ice-containing lunar soil sample has sublimated. At this time, the moisture sublimation rate per unit mass of the ice-containing lunar soil measured is the vacuum thermally induced sublimation loss rate of the ice-containing lunar soil sample; Step S14, sequentially adjust the preset temperature set by the heating device (such as 40°C, 60°C, 80°C, 100°C, etc.), and repeat the above steps S11 to S13 to obtain the vacuum thermally induced sublimation loss rate of the ice-containing lunar soil sample at different heating temperatures; Step S15, replace the ice-containing lunar soil sample, and sequentially change the particle size, moisture content, density, and particle size parameters of the ice-containing lunar soil sample, and repeat the above steps S11 to S14 to obtain the vacuum thermally induced sublimation loss rate of the ice-containing lunar soil sample under the influence of different heating temperatures and different sample physical property parameters.

[0050] In a specific embodiment of the present invention, the sublimation test is to test the vacuum thermally induced sublimation loss rate of the ice-containing lunar soil sample in a spilled state, including the following steps: Step S21, use the robotic arm 43 to pour the transferred ice-containing lunar soil sample onto the tray 461 of the second weighing system 46 in a natural spilling manner and measure the initial mass of the sample ; Step S22, let the ice-containing lunar soil sample stand still on the tray 461 (for example, control the tray temperature at -20°C), and measure the mass of the ice-containing lunar soil sample at each interval , and calculate the sublimation rate of the water in the ice-containing lunar soil for each time period and the sublimation rate of water per unit mass of the ice-containing lunar soil ; Wherein, (1); (2); Step S23 until the sublimation rate of the water in the ice-containing lunar soil measured finally is less than the drift amount during the balance calibration, that is, it is considered that all the water in the ice-containing lunar soil sample has sublimated. At this time, the sublimation rate of water per unit mass of the ice-containing lunar soil measured is the vacuum thermally induced sublimation loss rate of the ice-containing lunar soil sample; Step S24, adjust the balance temperature control system to control the tray temperature (for example, control the tray temperature at -40°C, -60°C, -80°C, etc.), replace the ice-containing lunar soil sample, and successively change the particle size, water content, density, and particle size parameters of the ice-containing lunar soil sample, and repeat the above steps S21 to S23 to obtain the vacuum thermally induced sublimation loss rate of the ice-containing lunar soil under the throwing and feeding state under different temperature conditions and different sample physical property parameters.

[0051] In a specific embodiment of the present invention, the sublimation test is to test the vacuum thermally induced sublimation loss rate of the ice-containing lunar soil sample under different stacking patterns, including the following steps: Step S31, use the robotic arm 43 to pour the transferred ice-containing lunar soil sample into the lunar soil tray 473 of the third balance system 47, and measure the initial mass of the ice-containing lunar soil sample ; Step S32, let the ice-containing lunar soil sample stand still on the tray (for example, control the tray temperature at -20°C), and measure the mass of the ice-containing lunar soil sample at each interval , and calculate the sublimation rate of the water in the ice-containing lunar soil for each time period and the sublimation rate of water per unit mass of the ice-containing lunar soil ; Step S33, until the sublimation rate of the water in the ice-containing lunar soil measured finally is less than the drift amount during the balance calibration, that is, it is considered that all the water in the ice-containing lunar soil sample has sublimated. At this time, the sublimation rate of water per unit mass of the ice-containing lunar soil measured is the vacuum thermally induced sublimation loss rate of the ice-containing lunar soil sample; Step S34, change the shape of the lunar soil tray, and repeat the above steps S31 to S33 to obtain the vacuum thermally induced sublimation loss rate of the ice-containing lunar soil sample under different stacking patterns; Step S35: Adjust the temperature of the balance temperature control system for the tray (for example, control the tray temperature at -40°C, -60°C, -80°C, etc.), replace the ice-containing lunar soil sample, and successively change the particle size, moisture content, density, and particle size parameters of the ice-containing lunar soil sample. Repeat the above steps S31 to S34 to obtain the vacuum thermosublimation loss rate of the ice-containing lunar soil sample under different temperature conditions and different sample physical property parameters.

[0052] The embodiments described above only represent the implementation manners of the present invention. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the patent of the present invention. The present invention can also be implemented in other specific manners or other specific forms without departing from the gist or essential features of the present invention. Therefore, the described implementation manners should be regarded as illustrative rather than restrictive in any aspect. The scope of the present invention should be defined by the appended claims, and any equivalent changes to the intention and scope of the claims should also be included within the scope of the present invention.

Claims

1. A test system for the vacuum thermosublimation loss rate of ice-containing asteroid regolith, characterized in that, It includes a data acquisition system, as well as a sample preparation chamber, a first vacuum cryogenic chamber, a second vacuum chamber, and an in-situ detection simulation vacuum chamber that are connected in sequence; The sample preparation chamber is used to make a dry soil of the original lunar regolith into an ice-containing lunar regolith sample; The first vacuum cryogenic chamber is used to control the ice-containing lunar regolith sample to be maintained in a vacuum cryogenic environment to prevent sample loss; The second vacuum chamber is used to transfer the ice-containing lunar regolith sample stored in the first vacuum cryogenic chamber to the in-situ detection simulation vacuum chamber; The in-situ detection simulation vacuum chamber includes a vacuum tank, a cold plate is arranged in the vacuum tank, and a robotic arm, a balance system, and a heating device are arranged on the cold plate; the balance system includes a balance temperature control system and a sample receiving unit, and is used to weigh and test the vacuum thermosublimation loss rate of the ice-containing lunar regolith sample; The data acquisition system records the test data of the vacuum thermosublimation loss rate of the ice-containing lunar regolith in real time.

2. The test system according to claim 1, characterized in that, The balance temperature control system includes a sample support, a radiation shield, a first semiconductor refrigeration chip, a balance upper cover, a balance, a balance lower cover, a second semiconductor refrigeration chip, a balance support, and a balance base that are arranged in sequence from top to bottom. The radiation shield covers the balance. Covers are arranged around the balance, and a third semiconductor refrigeration chip is arranged outside the cover. The sample support is embedded on the radiation shield, one end of which is connected to the balance and the other end is connected to the sample receiving unit.

3. The test system according to claim 1, characterized in that, There are multiple balance systems, including a first balance system, a second balance system, and a third balance system. The first balance system, the second balance system, and the third balance system adopt balance temperature control systems with the same structure and sample receiving units with different structures.

4. The test system according to claim 3, characterized in that, The sample receiving unit of the first balance system includes a sample cup and a sample cup holder, and the sample cup holder is used to fix the sample cup; The sample receiving unit of the second balance system includes a tray, an infrared sensor bracket, and an infrared sensor. The infrared sensor bracket is used to adjust and fix the position of the infrared sensor so that the infrared sensor can test the sample temperature of the tray in real time; The sample receiving unit of the third balance system includes a funnel, a funnel bracket, a lunar regolith support, a tray, an infrared sensor, and an infrared sensor bracket; the funnel is arranged on the funnel bracket and is used to position the lunar regolith support. The lunar regolith support is arranged above the tray and is used to shape the pile of the ice-containing lunar regolith sample.

5. The test system according to claim 1, characterized in that, The first vacuum cryogenic chamber includes a liquid nitrogen cold finger, a first gate valve, a first vacuum system, and a primary vacuum transition chamber; The first gate valve is arranged on the transfer channel between the sample preparation chamber and the first vacuum cryogenic chamber. The first vacuum system and the liquid nitrogen cold finger are used to vacuum-freeze the ice-containing lunar regolith sample in the primary vacuum transition chamber.

6. The test system according to claim 1, characterized in that, The second vacuum chamber includes a first robotic gripper, a second robotic gripper, a second gate valve, a third gate valve, a second vacuum system, and a secondary vacuum transition chamber; The second gate valve is arranged on the transfer channel between the first vacuum cryogenic chamber and the second vacuum chamber. The first robotic gripper is used to transport the ice-containing lunar regolith sample from the first vacuum cryogenic chamber to the second vacuum chamber; The third gate valve is arranged on the transfer channel between the second vacuum chamber and the in-situ detection simulation vacuum chamber, and the second mechanical gripper is used to transport the ice-containing lunar soil sample from the second vacuum chamber to the in-situ detection simulation vacuum chamber.

7. A method for testing the vacuum thermosublimation loss rate of ice-containing asteroid regolith using the test system for the vacuum thermosublimation loss rate of ice-containing asteroid regolith according to any one of claims 1 to 6, characterized in that, It includes the following steps: Initialize and set the parameters of the vacuum thermosublimation loss rate test system for the ice-containing lunar soil. Calibrate the stability of the balance system in the in-situ detection simulation vacuum chamber. Make a series of ice-containing lunar soil samples with different physical property parameters from the dry lunar soil of the original lunar soil in the sample preparation chamber. Transport the ice-containing lunar soil sample from the sample preparation chamber to the first vacuum low-temperature chamber for vacuum freezing. After transporting the vacuum-frozen ice-containing lunar soil sample to the second vacuum chamber, reduce the vacuum degree of the second vacuum chamber, and then transport the ice-containing lunar soil sample from the second vacuum chamber to the in-situ detection simulation vacuum chamber. After the ice-containing lunar soil sample is transferred into the in-situ detection simulation vacuum chamber, conduct a sublimation test, measure the weight change of the ice-containing lunar soil sample before and after sublimation, and obtain the vacuum thermosublimation loss rate of the ice-containing lunar soil sample.

8. The method according to claim 7, characterized in that, The sublimation test includes testing the vacuum thermosublimation loss rate of the ice-containing lunar soil sample at different heating temperatures, and includes the following steps: Step S11, place the transferred ice-containing lunar soil sample on the balance system to measure the initial mass of the sample , Step S12: Transfer the ice-containing lunar soil sample to a heating device that has reached a preset temperature for heating, and take out the ice-containing lunar soil sample from the heating device every interval, place it on a balance system to measure the mass of the ice-containing lunar soil sample at this time , then put the ice-containing lunar soil sample back into the heating device for heating, and calculate the sublimation rate of water in the ice-containing lunar soil and the sublimation rate of water per unit mass of the ice-containing lunar soil during each time period; ; Step S13, until the moisture sublimation rate of the ice-containing lunar regolith measured finally is less than the drift amount during the balance calibration, that is, it is considered that all the moisture in the ice-containing lunar regolith sample has sublimated. At this time, the moisture sublimation rate per unit mass of the ice-containing lunar regolith measured is the vacuum thermally induced sublimation loss rate of the ice-containing lunar regolith sample; Step S14, sequentially adjust the preset temperature set by the heating device, and repeat the above steps S11 to S13 to obtain the vacuum thermosublimation loss rate of the ice-containing lunar soil sample at different heating temperatures. Among them, (1); (2); In formulas (1) and (2), is the sublimation rate of water in the ice-containing lunar soil,[[]] is the sublimation rate of water per unit mass of the ice-containing lunar soil,[[]] is the initial mass of the ice-containing lunar soil sample,[[]] is for every the mass after the change at intervals of the ice-containing lunar soil sample,[[]] is the time interval.[[]] 9. The method according to claim 7, wherein The sublimation test includes testing the vacuum thermosublimation loss rate of the ice-containing lunar soil sample in the spilled state, and includes the following steps: Step S21: Pour the delivered ice-containing lunar soil sample onto the balance system in a natural sprinkling manner to measure the initial mass of the sample ; Step S22, let the ice-containing lunar regolith sample stand still in the balance system and measure the mass of the ice-containing lunar regolith sample every interval , calculate the sublimation rate of water in the ice-containing lunar regolith for each time period and the sublimation rate of water per unit mass of the ice-containing lunar regolith ; Step S23, until the moisture sublimation rate of the ice-containing lunar regolith measured finally is less than the drift amount during the balance calibration, that is, it is considered that all the moisture in the ice-containing lunar regolith sample has sublimated. At this time, the moisture sublimation rate per unit mass of the ice-containing lunar regolith measured is the vacuum thermally induced sublimation loss rate of the ice-containing lunar regolith sample; Step S24, adjust the temperature control temperature of the balance system, replace the ice-containing lunar soil samples with different physical property parameters, and repeat the above steps S21 to S23 to obtain the vacuum thermosublimation loss rate of the ice-containing lunar soil in the spilled sample state under different temperature conditions and different physical property parameters. Among them, (1); (2); In formulas (1) and (2), is the sublimation rate of water in the ice-containing lunar soil,[ is the sublimation rate of water per unit mass of the ice-containing lunar soil,[ is the initial mass of the ice-containing lunar soil sample,[ is the mass of the ice-containing lunar soil sample after each interval change,[ is the time interval.[ 10. The method according to claim 7, wherein The sublimation test includes testing the vacuum thermosublimation loss rate of the ice-containing lunar soil sample under different pile types, and includes the following steps: Step S31: Pour the delivered ice-containing lunar soil sample into the lunar soil tray of the balance system to measure the initial mass of the ice-containing lunar soil sample ; Step S32, let the ice-containing lunar soil sample stand still in the balance system and measure the mass of the ice-containing lunar soil sample every interval, calculate the moisture sublimation rate of the ice-containing lunar soil in each time period and the moisture sublimation rate per unit mass of the ice-containing lunar soil ; Step S33, until the sublimation rate of water in the ice-containing lunar soil measured finally is less than the drift amount during the balance calibration, that is, it is considered that all the water in the ice-containing lunar soil sample has sublimated. At this time, the sublimation rate of water per unit mass of the ice-containing lunar soil measured is the vacuum thermally induced sublimation loss rate of the ice-containing lunar soil sample; Step S34, change the shape of the lunar soil support, and repeat the above steps S31 to S33 to obtain the vacuum thermosublimation loss rate of the ice-containing lunar soil sample under different pile types. Among them, (1); (2); In Formula (1) and Formula (2), is the sublimation rate of water in the ice-containing lunar soil,[ is the sublimation rate of water per unit mass of the ice-containing lunar soil,[ is the initial mass of the ice-containing lunar soil sample,[ is the mass of the ice-containing lunar soil sample after each interval change,[ is the time interval.[

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