Simulation system and simulation test method for rock weathering in extreme environment of Mars

Abstract

The invention discloses a rock weathering simulation system in an extreme environment of Mars. The rock weathering simulation system in the extreme environment of Mars comprises a vacuum chamber, a storage structure, a temperature simulation unit, a gas circulation simulation unit, a wind speed simulation unit and an illumination simulation unit. The invention further discloses a rock weathering simulation test method in the extreme environment of Mars. Compared with the prior art, the rock weathering simulation system under the Mars extreme environment can synchronously simulate extreme environments such as a vacuum environment, an atmospheric environment, a temperature environment, an illumination environment and a sand and dust environment on the surface of Mars; and monitoring the changes of the quality, porosity, surface deformation and the like of the sample in the weathering process under the Mars extreme environment of the simulation system, and systematically evaluating the weathering characteristics of the sample.

Description

Technical Field

[0001] The present invention relates to the field of testing the physical and mechanical properties of rocks in extreme environments, and in particular to a rock weathering simulation system and a simulation test method in an extreme Martian environment. Background Art

[0002] Mars is the planet most similar to Earth among the near-Earth planets. Scientific research on Mars can help us better understand the early evolutionary history of Earth and the origin of life. At the same time, the rocks and soil materials on the surface of Mars are important record carriers of the geological evolution history of Mars. Using the known knowledge of the natural environment of the surface to study the rock and soil materials on the surface of Mars and establish the corresponding ground-like simulations will have great scientific research value for better understanding the evolution of Mars. The average air pressure on Mars is 0.75kPa; the main component of the atmosphere is carbon dioxide, accounting for 95%; the average surface temperature is -130 to 20℃; the extreme wind speed is 150m / s; the main surface terrain is wind-eroded desert landform; the gravity acceleration is 3.72m / s 2 ; The average irradiance is 589W / m 2 .

[0003] Most of the existing technologies simulate the surface environment of Mars, taking into account the low-pressure thermal environment and wind speed of Mars, and the various parts work together to successfully reproduce the unique low-pressure thermal environment of Mars. However, there is still a lack of research on what specific changes will occur to rock materials after long-term exposure to such extreme conditions on Mars, especially how they are affected by weathering.

[0004] Therefore, how to provide a rock weathering simulation system under the extreme environment of Mars, so that it can specifically carry out research on the weathering characteristics of rock samples under the extreme environment of Mars and achieve the technical effect of synchronously simulating the extreme environments such as the vacuum environment, atmospheric environment, temperature environment, light environment and dust environment on the surface of Mars, is a technical problem that technical personnel in this field urgently need to solve. Summary of the invention

[0005] In view of the problems existing in the prior art, the technical problem to be solved by the present invention is to provide a more comprehensive simulation system and evaluation method to carry out research specifically on the weathering characteristics of rock samples in the extreme environment of Mars, so that the simulation system can realize the synchronous simulation of extreme environments such as the vacuum environment, atmospheric environment, temperature environment, lighting environment and dust environment on the surface of Mars, and make a systematic evaluation of the weathering characteristics of the rock by analyzing the changes in the physical and mechanical properties of the rock before and after experiencing the extreme environment of Mars.

[0006] To achieve the above-mentioned purpose, the present invention provides a rock weathering simulation system under the extreme environment of Mars, the rock weathering simulation system under the extreme environment of Mars comprising: a vacuum chamber, the vacuum chamber comprising a vacuum chamber body and a vacuum chamber cover, the vacuum chamber body presenting a cubic box structure, the vacuum chamber cover being located at the top of the vacuum chamber body and being sealed and connected to the vacuum chamber body; a storage structure, the storage structure being located in the vacuum chamber body, the storage structure comprising a loading platform and a loading tray, the loading platform being located on the bottom surface of the vacuum chamber body, the loading tray being located on the loading platform, and the sample being located in the loading tray; a temperature simulation unit, the temperature simulation unit being used to The temperature inside the chamber is controlled; a gas circulation simulation unit, the gas circulation simulation unit comprises an inflation structure and an exhaust structure, the inflation structure is used to fill the interior of the vacuum chamber with carbon dioxide gas, methane gas and nitrogen gas, and the exhaust structure is used to evacuate the interior of the vacuum chamber; a wind speed simulation unit, the wind speed simulation unit is used to control the dust phenomenon inside the vacuum chamber; a light simulation unit, the light simulation unit is arranged on the upper part of one side of the inner wall of the vacuum chamber, the light simulation unit comprises a spectrometer and an ultraviolet radiation light source, the ultraviolet radiation light source is located above the spectrometer, and the ultraviolet radiation light source is connected to the spectrometer.

[0007] In the first aspect, the temperature simulation unit includes: a soil trough, which has a circular ring structure, is located on the storage platform, and the soil trough cover is arranged on the outside of the storage plate; an infrared heating cage, which has a cubic box structure, the open end of the infrared heating cage is located on the storage platform, and the infrared heating cage cover is arranged on the periphery of the soil trough.

[0008] In the first aspect, the rock weathering simulation system under the extreme environment of Mars also includes a measuring unit and a numerical control terminal, wherein the measuring unit includes: a vacuum gauge, the probe of the vacuum gauge is located inside the vacuum chamber; a gas detector, the probe of the gas detector is located inside the vacuum chamber; a pressure sensor, the pressure sensor is arranged at the bottom of the storage tray; a PIV system, the PIV system is arranged adjacent to the inner wall of the soil trough; a high-precision industrial camera, the high-precision industrial camera is located inside the soil trough, and the high-precision industrial camera is arranged on one side of the PIV system; a temperature sensor, the temperature sensor is located inside the soil trough, and the temperature sensor is arranged on the side of the high-precision industrial camera away from the PIV system; a temperature controller, the temperature controller is connected to the temperature sensor; wherein the storage tray is located between the PIV system and the high-precision industrial camera; the temperature controller is connected to the infrared heating cage; the data output end of the vacuum gauge, the data output end of the gas detector, the pressure sensor, the PIV system, the high-precision industrial camera, the temperature controller, and the spectrometer are all connected to the numerical control terminal.

[0009] In the first aspect, the temperature simulation unit further includes: a liquid nitrogen storage tank; a heat sink, which is arranged around the inner periphery of the vacuum chamber; two liquid nitrogen tubes, one end of which is fixedly connected to the output end of the liquid nitrogen storage tank, and the other end of which is fixedly connected to one end of the heat sink through a first flange; one end of the other liquid nitrogen tube is fixedly connected to the input end of the liquid nitrogen storage tank, and the other end of the other liquid nitrogen tube is fixedly connected to the other end of the heat sink through a second flange; two liquid nitrogen control valves, one of which is arranged at one end of one of the liquid nitrogen tubes close to the liquid nitrogen storage tank, and the other of which is arranged at one end of the other of the liquid nitrogen tubes close to the liquid nitrogen storage tank; a first cold trap, which is arranged on the other of the liquid nitrogen tubes, and the first cold trap is located between the other of the liquid nitrogen control valves and the second flange.

[0010] In the first aspect, the inflation structure includes: a CH4 gas cylinder; a first gas pipe, one end of which is connected to the output end of the CH4 gas cylinder; an N2 gas cylinder; a second gas pipe, one end of which is connected to the output end of the N2 gas cylinder, and the other end of the second gas pipe is connected to the other end of the first gas pipe; a third gas pipe, one end of which is connected to the connecting end of the first gas pipe and the second gas pipe; a CO2 gas cylinder; a fourth gas pipe, one end of which is connected to the output end of the CO2 gas cylinder, and the other end of the fourth gas pipe is connected to the other end of the third gas pipe; a fifth gas pipe, one end of which is connected to the connecting end of the third gas pipe and the fourth gas pipe, and the other end of the fifth gas pipe is connected to the third gas pipe through the third method. A flange is connected to the wind speed simulation unit; four gas control valves, the first of which is arranged on the first gas pipeline, the second of which is arranged on the third gas pipeline, the third of which is arranged on the fourth gas pipeline, and the fourth of which is arranged on the fifth gas pipeline; three mass flow meters, the first of which is arranged on the output side of the first gas control valve on the first gas pipeline, the second of which is arranged on the output side of the second gas control valve on the third gas pipeline, and the third of which is arranged on the output side of the third gas control valve on the fourth gas pipeline; a second cold trap, the second cold trap is arranged on the output side of the fourth gas control valve on the fifth gas pipeline.

[0011] In the first aspect, the exhaust structure includes: a vacuum pump; an exhaust pipe, one end of which is connected to the vacuum pump, and the other end of which is connected to the vacuum chamber through a fourth flange; an exhaust control valve, which is arranged on the exhaust pipe; and a third cold trap, which is arranged between the fourth flange and the exhaust control valve.

[0012] In the first aspect, the wind speed simulation unit includes: a high-pressure gas tank; a sand storage tank, one end of the sand storage tank is connected to the high-pressure gas tank through a sand blowing pipe; a sixth gas pipe, one end of the sixth gas pipe is connected to the other end of the sand storage tank, the other end of the sixth gas pipe is connected to the fifth gas pipe, and the connecting end of the sixth gas pipe and the fifth gas pipe is located between the fourth control valve and the second cold trap; the sixth gas pipe is provided with a fifth control valve; a fan, the air outlet of the fan is provided with a filter, and the fan is arranged on the upper part of the inner side wall of the vacuum chamber; wherein, the other end of the fifth gas pipe is connected to the air inlet of the fan through a third flange, and the fan is connected to the CNC terminal.

[0013] The present invention also provides a rock weathering simulation test method under the extreme environment of Mars. The simulation test method is used for the use of the rock weathering simulation system under the extreme environment of Mars. The rock weathering simulation method under the extreme environment of Mars comprises: placing the sample on a storage tray inside the soil trough, covering the vacuum hatch cover, and monitoring the quality of the sample in real time through a pressure sensor; turning on a high-precision industrial camera to aim at the sample; turning on the vacuum pump to stabilize the air pressure in the vacuum cabin at 0.75 kPa, turning on the CO2 gas cylinder and the blower, and observing the CO2 content monitored by the gas detector until the monitored CO2 content stabilizes to 95%; then turning on the N2 gas cylinder and the CH4 gas cylinder at the same time to keep the CO2 content unchanged and to make the N2 content 3 %, and a trace amount of CH4 to simulate the atmospheric composition on the surface of Mars; open the liquid nitrogen storage tank and the liquid nitrogen control valve to transport the liquid nitrogen to the heat sink tube, so that the temperature in the vacuum chamber is reduced to -130°C; turn on the ultraviolet radiation light source and the spectrometer, and adjust the irradiance of the ultraviolet radiation light source by controlling the spectrometer to simulate the irradiation of the surface of Mars by the sun; open the high-pressure gas tank and the fifth control valve to allow the gas coming out of the high-pressure gas tank to carry out the silicon dioxide particles in the sand storage tank to form dust-containing gas, and allow the dust-containing gas to form a wind velocity field through the fan to simulate the sand and dust phenomenon on the surface of Mars; monitor the flow velocity field in the vacuum chamber in real time through the PIV system; and evaluate the weathering characteristics of the sample after the weathering simulation is completed.

[0014] In the second aspect, the rock weathering simulation method under the extreme environment of Mars also includes drying and CT scanning the sample before weathering simulation to obtain the porosity n0 and density of the sample in the initial state, performing speckle spraying on the surface of the sample while ensuring that the speckle distribution is uniform, and taking an initial picture of the sample with a high-precision industrial camera.

[0015] In the second aspect, the weathering characteristic evaluation of the sample after the weathering simulation is completed includes: monitoring the mass of the sample in real time through the pressure sensor, taking the initial mass m0 and the final mass m1 of the sample, performing a CT scan on the sample after the weathering simulation is completed, and obtaining the final porosity n1 and density of the sample; monitoring the distribution changes of each speckle in the sample in real time through the high-precision industrial camera presented by the CNC terminal, and analyzing the displacement change Δd of each speckle on the surface of the sample after the weathering simulation is completed in combination with the initial image data of the sample. i , i is rounded and has a value range of 1 to 200; the mass loss rate Δm, porosity change rate Δn and surface deformation coefficient ε of the sample are calculated, the mass loss rate Δm of the sample is = (m0-m1) / m0×100%, the porosity change rate Δn of the sample is = (n0-n1) / n0×100%, the surface deformation coefficient of the sample is Among them, the Δd i is the displacement change of the ith point on the sample surface, a is the number of specks, a=200; weight coefficients are assigned, and the mass weight coefficient w1 is taken as 0.25, the porosity weight coefficient w2 is taken as 0.25, and the surface deformation weight coefficient w3 is taken as 0.5; the weathering index is proposed as p, then p=w1|Δm|+w2|Δn|+w3ε, wherein the larger the p value is, the higher the degree of weathering of the sample in the rock weathering system under the extreme environment of Mars.

[0016] Beneficial effects:

[0017] The rock weathering simulation system under extreme environment of Mars of the present invention is used for synchronous simulation of extreme environment such as vacuum environment, atmospheric environment, temperature environment, light environment and dust environment on the surface of Mars. The internal space of the vacuum chamber is sealed, and is composed of a vacuum chamber body and a vacuum chamber cover. The vacuum chamber cover contains a dynamic seal, so that the vacuum chamber cover is sealed and connected with the top opening of the vacuum chamber body. An observation port is provided on one side wall of the vacuum chamber body, and the observation port is provided with an observation window, which is convenient for observing the overall macroscopic situation inside the vacuum chamber; the loading platform is placed at the bottom of the vacuum chamber body, and the lower end surface of the loading platform is connected to two bottom columns, which is used to be placed at the bottom of the vacuum chamber body provided with heat sink tubes; the temperature simulation unit is used to simulate the extreme temperature on the surface of Mars in the vacuum chamber; the gas circulation simulation unit is used to simulate the air composition on the surface of Mars; the wind speed simulation unit is used to simulate the wind and sand phenomenon on the surface of Mars in the vacuum chamber; the light simulation unit is used to simulate the irradiation of the surface of Mars through a spectrometer and an ultraviolet radiation light source, and the irradiance is controlled to be 589W / m 2 ; In summary, the rock weathering simulation system under extreme Martian environment of the present invention can synchronously simulate extreme environments such as vacuum environment, atmospheric environment, temperature environment, lighting environment and dust environment on the surface of Mars. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of this specification or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 It is a structural schematic diagram of a rock weathering simulation system in an extreme Martian environment according to the present invention.

[0020] Reference numerals:

[0021] 11. Vacuum chamber; 12. Vacuum chamber cover; 13. Observation window;

[0022] 21. Loading platform; 22. Storage tray;

[0023] 31. Inflatable structure; 311. CH4 gas cylinder; 312. N2 gas cylinder; 313. CO2 gas cylinder; 314. Gas transmission control valve; 315. Second cold trap; 32. Pumping structure; 321. Vacuum pump; 322. Pumping pipe; 323. Pumping control valve; 324. Third cold trap;

[0024] 41. Spectrometer; 42. Ultraviolet radiation source

[0025] 51. Soil trough; 52. Infrared heating cage; 53. Liquid nitrogen storage tank; 54. Heat sink tube; 55. Liquid nitrogen tube; 56. Liquid nitrogen control valve; 57. First cold trap;

[0026] 61. Vacuum gauge; 62. Gas detector; 63. Pressure sensor; 64. PIV system; 65. High-precision industrial camera; 66. Temperature sensor; 67. Temperature controller;

[0027] 71. High-pressure gas tank; 72. Sand storage tank; 73. Sixth gas pipeline; 74. Fan;

[0028] 81. CNC terminal;

[0029] 101. Sample. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of this specification to clearly and completely describe the technical solutions in the embodiments of this specification. Obviously, the described embodiments are only part of the embodiments of this specification, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments in this specification belong to the scope of protection of the present invention.

[0031] Embodiment 1

[0032] like Figure 1 As shown, the present embodiment 1 provides a rock weathering simulation system under the extreme environment of Mars, and the rock weathering simulation system under the extreme environment of Mars includes: a vacuum chamber, the vacuum chamber includes a vacuum chamber body 11 and a vacuum chamber cover 12, the vacuum chamber body 11 is a cubic box structure, the vacuum chamber cover 12 is located at the top of the vacuum chamber body 11 and is sealed and connected to the vacuum chamber body 11; a storage structure, the storage structure is located in the vacuum chamber body 11, the storage structure includes a loading platform 21 and a storage tray 22, the loading platform 21 is located on the bottom surface of the vacuum chamber body 11, the storage tray 22 is located on the loading platform 21, and the sample 101 is located in the storage tray 22; a temperature simulation unit, the temperature simulation unit is used to The temperature inside the vacuum chamber is controlled; a gas circulation simulation unit, the gas circulation simulation unit includes an inflation structure 31 and an exhaust structure 32, the inflation structure 31 is used to fill the vacuum chamber with carbon dioxide gas, methane gas and nitrogen gas, and the exhaust structure 32 is used to evacuate the inside of the vacuum chamber; a wind speed simulation unit, the wind speed simulation unit is used to control the dust phenomenon inside the vacuum chamber; a light simulation unit, the light simulation unit is arranged on the upper part of one side of the inner wall of the vacuum chamber body 11, the light simulation unit includes a spectrometer 41 and an ultraviolet radiation light source 42, the ultraviolet radiation light source 42 is located above the spectrometer 41, and the ultraviolet radiation light source 42 is connected to the spectrometer 41.

[0033] The rock weathering simulation system under extreme environment of Mars of the present invention is used for synchronously simulating extreme environments such as vacuum environment, atmospheric environment, temperature environment, lighting environment and dust environment on the surface of Mars. The internal space of the vacuum chamber is sealed, and is composed of a vacuum chamber body 11 and a vacuum chamber cover 12. The vacuum chamber cover 12 contains a dynamic seal, so that the vacuum chamber cover 12 is sealed and connected to the top opening of the vacuum chamber body 11. An observation port is provided on one side wall of the vacuum chamber body 11, and the observation port is provided with an observation window 13, which is convenient for observing the overall macroscopic situation inside the vacuum chamber; the loading platform 21 is placed at the bottom of the vacuum chamber body 11, and the lower end surface of the loading platform 21 is connected to two bottom columns, which is used to be placed at the bottom of the vacuum chamber body 11 where a heat sink tube 54 is arranged; the temperature simulation unit is used to simulate the extreme temperature of the surface of Mars in the vacuum chamber; the gas circulation simulation unit is used to simulate the air composition on the surface of Mars; the wind speed simulation unit is used to simulate the wind and sand phenomenon on the surface of Mars in the vacuum chamber; the light simulation unit is used to simulate the irradiation of the surface of Mars through a spectrometer 41 and an ultraviolet radiation light source 42, and the irradiance is controlled to be 589W / m 2 ; In summary, the rock weathering simulation system under extreme Martian environment of the present invention can synchronously simulate extreme environments such as vacuum environment, atmospheric environment, temperature environment, lighting environment and dust environment on the surface of Mars.

[0034] In some possible implementations, the temperature simulation unit includes: a soil trough 51, which is a circular ring structure, is located on the storage platform, and is covered on the outside of the storage tray 22; an infrared heating cage 52, which is a cubic box structure, has an open end of the infrared heating cage 52 located on the storage platform, and is covered on the outside of the soil trough 51.

[0035] Specifically, the inner side of the soil groove 51 is used to place the placement tray 22 for placing the sample 101. There are multiple samples 101 placed in the placement tray 22. Each sample 101 has a different natural shape and a different surface roughness. At the same time, the average density of the multiple samples 101 is about 3g / cm 3 , and the sample 101 is suspended with basalt with a particle size range of 2 to 10 mm. The test on basalt with different surface roughness can better simulate the weathering process and achieve the ideal effect; the infrared heating cage 52 is connected to the temperature controller 67, and the infrared heating cage 52 is controlled by the temperature controller 67 to adjust the temperature; the infrared heating cage 52 and the soil trough 51 are both made of stainless steel and have good high temperature resistance.

[0036] In some possible implementations, the rock weathering simulation system under the extreme environment of Mars also includes a measuring unit and a CNC terminal 81, wherein the measuring unit includes: a vacuum gauge 61, wherein the probe of the vacuum gauge 61 is located inside the vacuum chamber; a gas detector 62, wherein the probe of the gas detector 62 is located inside the vacuum chamber; a pressure sensor 63, wherein the pressure sensor 63 is arranged at the bottom of the storage tray 22; a PIV system 64, wherein the PIV system 64 is arranged adjacent to the inner wall of the soil trough 51; a high-precision industrial camera 65, wherein the high-precision industrial camera 65 is located inside the soil trough 51, and wherein the high-precision industrial camera 65 is arranged on one side of the PIV system 64; and a temperature sensor. The temperature sensor 66 is located inside the soil trough 51, and the temperature sensor 66 is arranged on the side of the high-precision industrial camera 65 away from the PIV system 64; the temperature controller 67 is connected to the temperature sensor 66; wherein the storage tray 22 is located between the PIV system 64 and the high-precision industrial camera 65; the temperature controller 67 is connected to the infrared heating cage 52; the data output end of the vacuum gauge 61, the data output end of the gas detector 62, the pressure sensor 63, the PIV system 64, the high-precision industrial camera 65, the temperature controller 67, and the spectrometer 41 are all connected to the CNC terminal 81.

[0037] Specifically, the vacuum gauge 61 is used to monitor the pressure in the vacuum chamber, and the gas detector 62 is used to detect the gas content in the vacuum chamber; the pressure sensor 63 is used to monitor the quality of the sample 101 in the storage tray 22 in real time; the PIV system 64 is used to measure the velocity distribution of the entire flow field in the vacuum chamber and provide high-resolution velocity field data, while visualizing the flow velocity through the numerical control terminal 81; the high-precision industrial camera 65 is used to photograph the sample 101 with a speckle pattern sprayed on the surface, and by comparing the displacement of the speckle pattern on the surface of the sample 101 before and after weathering, the strain and displacement field of the surface of the sample 101 are calculated, that is, Used to monitor the speckle changes on the surface of the rock sample 101 in real time, so as to measure its deformation field; the temperature sensor 66 is used to monitor the temperature changes in the vacuum chamber in real time, and the temperature sensor 66 is connected to the temperature controller 67, and combined with the infrared heating cage 52 to adjust the temperature in the vacuum chamber; a cable hole is opened on one side wall of the vacuum chamber body 11, and a cable perforator is provided at the cable hole, and the cable perforator is sealed and connected to the cable hole, and all cables in the vacuum chamber are passed through the cable perforator, and the cables are sealed and connected to the cable perforator to ensure that all cables in the vacuum chamber pass through while ensuring the airtightness of the vacuum chamber.

[0038] In some possible implementations, the temperature simulation unit further includes: a liquid nitrogen storage tank 53; a heat sink 54, wherein the heat sink 54 is arranged around the inner periphery of the vacuum chamber 11; two liquid nitrogen tubes 55, wherein one end of one of the liquid nitrogen tubes 55 is fixedly connected to the output end of the liquid nitrogen storage tank 53, and the other end of one of the liquid nitrogen tubes 55 is fixedly connected to one end of the heat sink 54 through a first flange; one end of the other of the liquid nitrogen tubes 55 is fixedly connected to the input end of the liquid nitrogen storage tank 53, and the other end of the other of the liquid nitrogen tubes 55 is fixedly connected to the input end of the liquid nitrogen storage tank 53. One end is fixedly connected to the other end of the heat sink tube 54 through a second flange; two liquid nitrogen control valves 56, one of the liquid nitrogen control valves 56 is arranged at one end of one of the liquid nitrogen tubes 55 close to the liquid nitrogen storage tank 53, and the other liquid nitrogen control valve 56 is arranged at one end of the other liquid nitrogen tube 55 close to the liquid nitrogen storage tank 53; a first cold trap 57, the first cold trap 57 is arranged on the other liquid nitrogen tube 55, and the first cold trap 57 is located between the other liquid nitrogen control valve 56 and the second flange.

[0039] Specifically, two openings are provided on the upper part of an inner side wall of the vacuum chamber body 11, and a first flange and a second flange are respectively provided at the two openings, so that the liquid nitrogen storage tank 53 is connected to both ends of the heat sink tube 54 while maintaining the airtightness in the vacuum chamber; the liquid nitrogen in the liquid nitrogen storage tank 53 is transported to the heat sink tube 54, and the purpose of cooling the inside of the vacuum chamber is achieved by transporting the liquid nitrogen in the heat sink tube 54, and the flow rate of the liquid nitrogen in the heat sink tube 54 is controlled by the liquid nitrogen control valve 56 at the output end of the liquid nitrogen storage tank 53, and the temperature of the heat sink tube 54 is adjusted according to the temperature. The change of temperature requires more precise adjustment of the liquid nitrogen content in the heat sink; the heat sink tube 54 is a whole, which is laid on the bottom surface and left and right sides of the vacuum chamber body 11, so that the temperature in the vacuum chamber is uniform, and the liquid nitrogen flows from the output end of the liquid nitrogen storage tank 53 to the heat sink tube 54, and then flows out through the other end of the heat sink tube 54, and enters the liquid nitrogen storage tank 53 through the input end of the liquid nitrogen storage tank 53, so as to achieve the circulation of liquid nitrogen; the first cold trap 57 is used to condense the vaporized liquid nitrogen into liquid; the heat sink tube 54 is made of aluminum and can respond to temperature changes relatively quickly.

[0040] In some possible implementations, the inflatable structure 31 includes: a CH4 gas cylinder 311; a first gas pipe, one end of which is connected to the output end of the CH4 gas cylinder 311; an N2 gas cylinder 312; a second gas pipe, one end of which is connected to the output end of the N2 gas cylinder 312, and the other end of the second gas pipe is connected to the other end of the first gas pipe; a third gas pipe, one end of which is connected to the connecting end of the first gas pipe and the second gas pipe; a CO2 gas cylinder 313; a fourth gas pipe, one end of which is connected to the output end of the CO2 gas cylinder 313, and the other end of the fourth gas pipe is connected to the other end of the third gas pipe; a fifth gas pipe, one end of which is connected to the connecting end of the third gas pipe and the fourth gas pipe, and the other end of the fifth gas pipe is connected to the CO2 gas cylinder 313 through a third flange. The wind speed simulation unit is connected; four gas control valves 314, the first gas control valve 314 is arranged on the first gas pipeline, the second gas control valve 314 is arranged on the third gas pipeline, the third gas control valve 314 is arranged on the fourth gas pipeline, and the fourth gas control valve 314 is arranged on the fifth gas pipeline; three mass flow meters, the first mass flow meter is arranged on the output side of the first gas control valve 314 on the first gas pipeline, the second mass flow meter is arranged on the output side of the second gas control valve 314 on the third gas pipeline, and the third mass flow meter is arranged on the output side of the third gas control valve 314 on the fourth gas pipeline; a second cold trap 315, the second cold trap 315 is arranged on the output side of the fourth gas control valve 314 on the fifth gas pipeline.

[0041] Specifically, the CO2 gas cylinder 313, the N2 gas cylinder 312, and the CH4 gas cylinder 311 are respectively arranged in different branches, and each branch is provided with its own control valve and mass flow meter; when inflating, the CO2 gas cylinder 313, the N2 gas cylinder 312, the CH4 gas cylinder 311 and the corresponding gas supply control valve 314 of each gas cylinder are opened to allow CO2, N2, and CH4 gases to enter the vacuum chamber to simulate the gas composition and content on the surface of Mars. When the CO2, N2, and CH4 gas content in the vacuum chamber meets the requirements, the corresponding gas supply control valve 314 and the fourth gas supply control valve 314 are closed to ensure the stability of the gas content in the chamber; the mass flow meter and gas supply control valve 314 of each gas cylinder are convenient for independently and conveniently adjusting the inflation amount of each gas.

[0042] In some possible implementations, the exhaust structure 32 includes: a vacuum pump 321; an exhaust pipe 322, one end of which is connected to the vacuum pump 321, and the other end of which is connected to the vacuum chamber 11 through a fourth flange; an exhaust control valve 323, which is arranged on the exhaust pipe 322; and a third cold trap 324, which is arranged between the fourth flange and the exhaust control valve 323.

[0043] Specifically, an exhaust hole is opened on an inner side wall of the vacuum chamber body 11, and a fourth flange is arranged at the exhaust hole, so that the exhaust pipe 322 is connected to the inside of the vacuum chamber while ensuring the airtightness of the inside of the vacuum chamber; when exhausting, the gas in the vacuum chamber first passes through the third cold trap 324 to capture volatile substances and solid particles or liquids, and then enters the vacuum pump 321, which reduces the harmful substances entering the pump and also protects the vacuum pump 321.

[0044] In some possible implementations, the wind speed simulation unit includes: a high-pressure gas tank 71; a sand storage tank 72, one end of the sand storage tank 72 is connected to the high-pressure gas tank 71 through a sand blowing pipe; a sixth gas pipe 73, one end of the sixth gas pipe 73 is connected to the other end of the sand storage tank 72, the other end of the sixth gas pipe 73 is connected to the fifth gas pipe, and the connecting end of the sixth gas pipe 73 and the fifth gas pipe is located between the fourth control valve and the second cold trap 315; the sixth gas pipe 73 is provided with a fifth control valve; a fan 74, the air outlet of the fan 74 is provided with a filter, and the fan 74 is arranged on the upper part of the inner side wall of the vacuum chamber 11; wherein, the other end of the fifth gas pipe is connected to the air inlet of the fan 74 through a third flange, and the fan 74 is connected to the CNC terminal 81.

[0045] Specifically, the fan 74 can simulate a fixed wind speed and control the wind speed to vary in the range of 0m / s-20m / s; the liquid CO2 in the high-pressure gas tank 71 is pressed out of the tank, and the liquid CO2 quickly turns into gaseous CO2 due to changes in pressure and temperature. The CO2 gas enters the sand storage tank 72 and is mixed with the SiO2 particles flowing out of the sand storage tank 72 to form a dust-containing gas. The gas is transported to the vacuum chamber 11 through a transport pipeline by the fan 74, which better simulates the sand and dust phenomenon on the surface of Mars, and a filter is arranged in front of the fan 74 to prevent larger sand and stone particles from entering the vacuum chamber and causing irreversible damage to the experimental instruments; when transporting CO2, N2, and CH4 gases into the vacuum chamber, the fan 74 needs to be turned on.

[0046] Embodiment 2

[0047] like Figure 1As shown, the second embodiment of the present invention provides a rock weathering simulation test method under the extreme environment of Mars, and the simulation test method is used for the simulation test of a rock weathering simulation system under the extreme environment of Mars described in the first embodiment. The rock weathering simulation test method under the extreme environment of Mars includes: placing the sample 101 on the storage tray 22 inside the soil trough 51, covering the vacuum cabin cover 12, and monitoring the quality of the sample 101 in real time through the pressure sensor 63; turning on the high-precision industrial camera 65 to aim at the sample 101; turning on the vacuum pump 321 to stabilize the air pressure in the vacuum cabin at 0.75kPa, turning on the CO2 gas cylinder 313 and the fan 74, and observing the CO2 content monitored by the gas detector 62 until the monitored CO2 content stabilizes to 95%; then turning on the N2 gas cylinder 312 and the CH4 gas cylinder 311 at the same time to keep the CO2 content The amount of N2 is kept unchanged, and the content of CH4 is kept at 3% to simulate the atmospheric composition on the surface of Mars; the liquid nitrogen storage tank 53 and the liquid nitrogen control valve 56 are opened to transport the liquid nitrogen to the heat sink tube 54, so that the temperature in the vacuum chamber is reduced to -130°C; the ultraviolet radiation source 42 and the spectrometer 41 are turned on, and the irradiance of the ultraviolet radiation source 42 is adjusted by controlling the spectrometer 41 to simulate the irradiation of the surface of Mars by the sun; the high-pressure gas tank 71 and the fifth control valve are opened to allow the gas coming out of the high-pressure gas tank 71 to carry out the silicon dioxide particles in the sand storage tank 72 to form dust-containing gas, and the dust-containing gas is passed through the fan 74 to form a wind velocity field to simulate the dust phenomenon on the surface of Mars; the flow velocity field in the vacuum chamber is monitored in real time by the PIV system 64; after the weathering simulation is completed, the weathering characteristics of the sample 101 are evaluated.

[0048] Specifically, when opening the corresponding gas cylinder, the corresponding gas supply control valve 314 of the gas cylinder should also be opened; when opening the N2 gas cylinder 312 and the CH4 gas cylinder 311 at the same time, the CO2 gas content should be kept constant. Since the N2 content in the Martian atmosphere is relatively low, accounting for about 3%, and the CH4 content is even more negligible, the CH4 gas cylinder 311 should be closed first to make the CH4 content less than the N2 content, and then the N2 gas cylinder 312 should be closed to achieve the purpose of simulating the gas on the surface of Mars; the overall temperature in the vacuum chamber can be adjusted by controlling the infrared heating cage 52 and adjusting the liquid nitrogen delivery amount through the temperature controller 67, so that the temperature changes The range is -130℃-20℃; when simulating rock weathering of sample 101 in the extreme environment of Mars, it is necessary to monitor the quality of sample 101 in the storage tray 22, the change of surface speckle, etc. in real time; in addition, before using the rock weathering simulation system in the extreme environment of Mars to conduct a weathering simulation test on sample 101, it is necessary to check whether each equipment and instrument can operate normally. If they can operate normally, cover the vacuum cabin cover 12 and open the CO2 cylinder 313, input CO2 gas into the vacuum cabin 11, and check whether there is leakage outside the vacuum cabin 11 to check the air tightness of the whole set of equipment.

[0049] It should be noted that the rock weathering simulation test method under the extreme environment of Mars in the second embodiment is used for the simulation test of the rock weathering simulation system under the extreme environment of Mars described in the first embodiment. Therefore, the performance principle of the rock weathering simulation system under the extreme environment of Mars will not be repeated here. For the part not described in detail, please refer to the first embodiment.

[0050] In some possible implementations, the rock weathering simulation test method under the extreme environment of Mars also includes drying and CT scanning the sample 101 before the weathering simulation to obtain the porosity n0 and density of the sample 101 in the initial state, and performing speckle spraying on the surface of the sample 101 to ensure that the speckle distribution is uniform, and using a high-precision industrial camera 65 to take an initial picture of the sample 101; after the weathering simulation, the weathering characteristic evaluation of the sample 101 includes: the mass of the sample 101 monitored in real time by the pressure sensor 63, taking the initial mass m0 and the final mass m1 of the sample 101, performing CT scanning on the sample 101 after the weathering simulation, and obtaining the final porosity n1 and density of the sample 101; the distribution change of each speckle in the sample 101 monitored in real time by the high-precision industrial camera 65 presented by the numerical control terminal 81, combined with the initial picture data of the sample 101, analyzing the displacement change Δd of each speckle on the surface of the sample 101 after the weathering simulation. i , i is rounded and has a value range of 1 to 200; the mass loss rate Δm, porosity change rate Δn and surface deformation coefficient ε of the sample 101 are calculated, the mass loss rate Δm of the sample 101 is Δm = (m0-m1) / m0×100%, the porosity change rate Δn of the sample 101 is Δn = (n0-n1) / n0×100%, the surface deformation coefficient ε of the sample 101 is Among them, the Δd i is the displacement change of the ith point on the surface of the sample 101, a is the number of specks, a=200; weight coefficients are assigned, and the mass weight coefficient w1 is taken as 0.25, the porosity weight coefficient w2 is taken as 0.25, and the surface deformation weight coefficient w3 is taken as 0.5; the weathering index is proposed as p, then p=w1|Δm|+w2|Δn|+w3ε, wherein the larger the p value means, the higher the degree of weathering of the sample 101 in the rock weathering system under the extreme environment of Mars.

[0051] Specifically, before the experiment begins, a speckle pattern is sprayed on the surface of the rock sample 101, and a high-precision industrial camera 65 is used to capture images of the rock in different states. By comparing the displacement of the speckle pattern in the previous and next images, the strain and displacement field of the rock surface are calculated, which is used to monitor the changes in the speckle on the surface of the rock sample 101 in real time, thereby measuring its deformation field. The larger the p value, the higher the degree of weathering of the sample 101 under the Martian environment simulation device, and the worse the physical and mechanical properties of the sample 101, thereby achieving the purpose of evaluating the degree of rock weathering in the Martian environment.

[0052] In summary, the rock weathering simulation system under extreme environment on Mars of the present invention can realize the synchronous simulation of extreme environments such as vacuum environment, atmospheric environment, temperature environment, lighting environment and dust environment on the surface of Mars. In addition, the weathering index p of rock under Martian environment and its calculation method are proposed, and the weathering characteristics of rock under Martian environment can be systematically evaluated, which has the following advantages: 1. The rock weathering simulation system under extreme environment on Mars provided by the present invention is provided with CO2 gas cylinders and CH4 gas cylinders, which can truly simulate the atmospheric composition and content on the surface of Mars. At the same time, CO2 gas and CH4 gas will also have a certain influence on the weathering of the sample. Equipped with CO2 gas cylinders and CH4 gas cylinders can more comprehensively reflect the rock weathering characteristics under Martian environment; 2. The rock weathering simulation system under extreme environment on Mars provided by the present invention is provided with high-pressure gas cylinders and sand storage tanks, which are jointly formulated into dust-containing gas, which better simulates the Martian environment. Dust phenomenon, and a filter is provided in front of the fan to filter out larger particles, reducing the impact of dust on the experimental process; 3. The present invention weathers the sample in a rock weathering simulation system under the extreme environment of Mars, and systematically evaluates the weathering characteristics of the sample by monitoring the changes in mass, porosity and surface deformation of the sample during the weathering process in the extreme environment of Mars in the simulation system, and proposes a weathering index p and its calculation method by quantifying the weathering degree of the rock, which is helpful to better understand the weathering mechanism of the rock under the Martian environment, so that the weathering degree can be accurately measured and recorded, and the comparability of the data is improved; 4. A rock weathering simulation system under the extreme environment of Mars provided by the present invention is helpful to further understand the geological evolution history of Mars, and can also provide valuable technical accumulation and important reference basis for the design and construction of other celestial environment simulation equipment in the future, so as to achieve more accurate reproduction of the unique conditions of various celestial bodies.

[0053] The preferred specific embodiments of the present invention are described in detail above. It should be understood that a person skilled in the art can make many modifications and changes based on the concept of the present invention without creative work. Therefore, any technical solution that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments based on the concept of the present invention on the basis of the prior art should be within the scope of protection determined by the claims.

Claims

1. A rock weathering simulation system under extreme Martian environment, characterized in that: The rock weathering simulation system under extreme Martian environment includes: A vacuum chamber, wherein the vacuum chamber comprises a vacuum chamber body and a vacuum chamber cover, wherein the vacuum chamber body is a cubic box structure, and the vacuum chamber cover is located on the top of the vacuum chamber body and is sealed and connected to the vacuum chamber body; A storage structure, the storage structure is located in the vacuum chamber, the storage structure includes a loading platform and a storage tray, the loading platform is located on the bottom surface of the vacuum chamber, the storage tray is located on the loading platform, and the sample is located in the storage tray; A temperature simulation unit, the temperature simulation unit is used to control the temperature inside the vacuum chamber; A gas circulation simulation unit, the gas circulation simulation unit comprising an inflation structure and an exhaust structure, the inflation structure is used to inflate the interior of the vacuum chamber with carbon dioxide gas, methane gas and nitrogen gas, and the exhaust structure is used to evacuate the interior of the vacuum chamber; A wind speed simulation unit, the wind speed simulation unit is used to control the dust phenomenon inside the vacuum chamber; The light simulation unit is arranged on the upper part of one side of the inner wall of the vacuum chamber, and comprises a spectrometer and an ultraviolet radiation light source. The ultraviolet radiation light source is located above the spectrometer and is connected to the spectrometer.

2. A rock weathering simulation system under extreme Martian environment as claimed in claim 1, characterized in that: The temperature simulation unit comprises: A soil trough, the soil trough is in a circular ring structure, the soil trough is located on the storage platform, and the soil trough cover is arranged outside the storage tray; The infrared heating cage is in a cubic box structure, the opening end of the infrared heating cage is located on the storage platform, and the infrared heating cage is arranged on the periphery of the soil trough.

3. A rock weathering simulation system under extreme Martian environment as claimed in claim 2, characterized in that: The rock weathering simulation system under extreme Martian environment also includes a measuring unit and a numerical control terminal, wherein the measuring unit includes: A vacuum gauge, wherein a probe of the vacuum gauge is located inside the vacuum chamber; A gas detector, wherein a probe of the gas detector is located inside the vacuum chamber; A pressure sensor, wherein the pressure sensor is arranged at the bottom of the storage tray; A PIV system, wherein the PIV system is disposed adjacent to an inner wall of the soil trough; A high-precision industrial camera, the high-precision industrial camera is located inside the soil trough, and the high-precision industrial camera is arranged on one side of the PIV system; A temperature sensor, the temperature sensor is located inside the soil trough, and the temperature sensor is arranged on a side of the high-precision industrial camera away from the PIV system; A temperature controller connected to the temperature sensor; Among them, the storage tray is located between the PIV system and the high-precision industrial camera; the temperature controller is connected to the infrared heating cage; the data output end of the vacuum gauge, the data output end of the gas detector, the pressure sensor, the PIV system, the high-precision industrial camera, the temperature controller, and the spectrometer are all connected to the CNC terminal.

4. A rock weathering simulation system under extreme Martian environment as claimed in claim 3, characterized in that: The temperature simulation unit also includes: Liquid nitrogen storage tanks; A heat sink tube, wherein the heat sink tube is arranged around the periphery of the vacuum chamber; Two liquid nitrogen tubes, one end of one of the liquid nitrogen tubes is fixedly connected to the output end of the liquid nitrogen storage tank, and the other end of one of the liquid nitrogen tubes is fixedly connected to one end of the heat sink tube through a first flange; one end of the other of the liquid nitrogen tubes is fixedly connected to the input end of the liquid nitrogen storage tank, and the other end of the other of the liquid nitrogen tubes is fixedly connected to the other end of the heat sink tube through a second flange; Two liquid nitrogen control valves, one of the liquid nitrogen control valves is arranged at one end of one of the liquid nitrogen pipes close to the liquid nitrogen storage tank, and the other of the liquid nitrogen control valves is arranged at one end of the other of the liquid nitrogen pipes close to the liquid nitrogen storage tank; A first cold trap, wherein the first cold trap is arranged on another of the liquid nitrogen pipes, and the first cold trap is located between another of the liquid nitrogen control valves and the second flange.

5. A rock weathering simulation system under extreme Martian environment as claimed in claim 4, characterized in that: The inflatable structure comprises: CH4 gas cylinders; A first gas delivery pipe, one end of which is connected to the output end of the CH4 gas cylinder; N2 gas cylinder; A second gas pipeline, one end of which is connected to the output end of the N2 gas cylinder, and the other end of which is connected to the other end of the first gas pipeline; a third gas pipeline, one end of which is connected to the connecting ends of the first gas pipeline and the second gas pipeline; CO2 cylinders; A fourth gas pipeline, one end of which is connected to the output end of the CO2 gas cylinder, and the other end of which is connected to the other end of the third gas pipeline; a fifth gas pipeline, one end of which is connected to the connecting ends of the third gas pipeline and the fourth gas pipeline, and the other end of which is connected to the wind speed simulation unit through a third flange; Four gas transmission control valves, the first gas transmission control valve is arranged on the first gas transmission pipe, the second gas transmission control valve is arranged on the third gas transmission pipe, the third gas transmission control valve is arranged on the fourth gas transmission pipe, and the fourth gas transmission control valve is arranged on the fifth gas transmission pipe; three mass flow meters, the first mass flow meter is arranged on the first gas pipeline at the output side of the first gas control valve, the second mass flow meter is arranged on the third gas pipeline at the output side of the second gas control valve, and the third mass flow meter is arranged on the fourth gas pipeline at the output side of the third gas control valve; A second cold trap, wherein the second cold trap is arranged on the output side of the fourth gas transmission control valve on the fifth gas transmission pipe.

6. A rock weathering simulation system under extreme Martian environment as claimed in claim 5, characterized in that: The air extraction structure comprises: Vacuum pump; an exhaust pipe, one end of which is connected to the vacuum pump, and the other end of which is connected to the vacuum chamber through a fourth flange; An air extraction control valve, wherein the air extraction control valve is arranged on the air extraction pipe; A third cold trap is arranged between the fourth flange and the air extraction control valve.

7. A rock weathering simulation system under extreme Martian environment as claimed in claim 6, characterized in that: The wind speed simulation unit comprises: High-pressure gas tanks; A sand storage tank, one end of which is connected to the high-pressure gas tank through a sand blowing pipeline; a sixth gas pipeline, one end of which is connected to the other end of the sand storage tank, the other end of which is connected to the fifth gas pipeline, and the connecting end of the sixth gas pipeline and the fifth gas pipeline is located between the fourth control valve and the second cold trap; a fifth control valve is provided on the sixth gas pipeline; A fan, wherein the air outlet of the fan is provided with a filter screen, and the fan is arranged on the upper part of the inner side wall of the vacuum chamber; Wherein, the other end of the fifth air supply pipe is connected to the air inlet of the fan through a third flange, and the fan is connected to the CNC terminal.

8. A rock weathering simulation test method under extreme Martian environment, the simulation test method is used for any simulation test of a rock weathering simulation system under extreme Martian environment as claimed in any one of claims 1 to 7, characterized in that: The rock weathering simulation test method under the extreme environment of Mars includes: The sample is placed on a tray inside the soil tank, and the vacuum hatch is covered. The quality of the sample is monitored in real time by a pressure sensor; a high-precision industrial camera is turned on and aimed at the sample; Turn on the vacuum pump to stabilize the air pressure in the vacuum chamber at 0.75 kPa, turn on the CO2 cylinder and the blower, and observe the CO2 content monitored by the gas detector until the monitored CO2 content stabilizes at 95%; then turn on the N2 cylinder and CH4 cylinder at the same time, keep the CO2 content unchanged, and make the N2 content at 3% and the CH4 content at a trace amount to simulate the atmospheric composition on the surface of Mars; Open the liquid nitrogen storage tank and liquid nitrogen control valve to transport liquid nitrogen to the heat sink tube and reduce the temperature in the vacuum chamber to -130°C; Turning on the ultraviolet radiation light source and the spectrometer, and adjusting the irradiance of the ultraviolet radiation light source by controlling the spectrometer to simulate the irradiation of the surface of Mars by the sun; Open the high-pressure gas tank and the fifth control valve, so that the gas from the high-pressure gas tank brings out the silicon dioxide particles in the sand storage tank to form dust-containing gas, and the dust-containing gas passes through the fan to form a wind speed field to simulate the dust phenomenon on the surface of Mars; Real-time monitoring of the flow velocity field in the vacuum chamber by a PIV system; After the weathering simulation is completed, the weathering characteristics of the sample are evaluated.

9. A rock weathering simulation test method under extreme Martian environment as claimed in claim 8, characterized in that: The rock weathering simulation test method under the extreme environment of Mars also includes drying and CT scanning the sample before weathering simulation to obtain the porosity n0 and density of the sample in the initial state, performing speckle spraying on the surface of the sample while ensuring that the speckle distribution is uniform, and using a high-precision industrial camera to take an initial picture of the sample.

10. A rock weathering simulation test method under extreme Martian environment as claimed in claim 9, characterized in that: After the weathering simulation is completed, the weathering characteristic evaluation of the sample includes: The mass of the sample is monitored in real time by the pressure sensor, and the initial mass m0 and the final mass m1 of the sample are taken. Performing CT scanning on the sample after the weathering simulation to obtain the final porosity n1 and density of the sample; The distribution changes of the speckles in the sample are monitored in real time by the high-precision industrial camera presented by the CNC terminal. Combined with the initial image data of the sample, the displacement change Δd of each speckle on the sample surface after the weathering simulation is completed is analyzed. i , i is rounded to an integer and its value range is 1 to 200; The mass loss rate Δm, porosity change rate Δn and surface deformation coefficient ε of the sample are calculated. The mass loss rate of the sample Δm=(m0-m1) / m0×100%, The porosity change rate of the sample Δn=(n0-n1) / n0×100%, The surface deformation coefficient of the sample Among them, the Δd i is the displacement change of the i-th point on the sample surface, a is the number of speckles, a=200; Assign weight coefficients, take the mass weight coefficient w1 as 0.25, the porosity weight coefficient w2 as 0.25, and the surface deformation weight coefficient w3 as 0.5; propose the weathering index as p, then p = w1|Δm|+w2|Δn|+w3ε, wherein the larger the p value means the higher the degree of weathering of the sample in the rock weathering system under the extreme environment of Mars.

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