Three-stage pressurization device for capturing atmosphere on surface of mars and regulation method

Abstract

The present application relates to a kind of three-stage Mars surface atmosphere trapping pressurization device and regulation and control method, innovatively proposed for Mars atmosphere trapping Roots, screw, piston / vortex three-stage series compression system configuration, primary Roots pump realizes large flow intake and preliminary pressurization under near-vacuum pressure, secondary screw pump realizes gas continuous delivery and pressurization, three-stage pump is further compressed to meet high pressure demand, can simultaneously meet high intake and high compression ratio under Mars environment.The regulation and control method includes single machine performance test and compression ratio regulation, series compression verification, product phase state verification three steps, the performance curve of single pump is determined by closed cycle measurement method, the compression ratio distribution is optimized, the flow matching of three-stage pump is realized and stable operation is verified by series compression verification, and carbon dioxide liquefaction effect is verified under simulated Mars low temperature environment.The present application provides high-performance trapping pressurization technical scheme and scientific performance regulation and control method for in-situ utilization of Mars atmosphere.

Description

Technical Field

[0001] This invention relates to the field of gas compression and collection technology, and more specifically to a three-stage Martian surface atmosphere capture and pressurization device and control method. Background Technology

[0002] In recent years, as human exploration of space has deepened, research on Mars has become a crucial part of the space exploration strategies of various countries. Limited by current transportation capabilities, the most important aspect of Mars technology is in-situ resource utilization. The Martian atmosphere, containing over 95% carbon dioxide, can be widely used in areas such as carbon dioxide jetting and in-situ oxygen production. Therefore, atmospheric capture technology is particularly important.

[0003] However, the Martian atmosphere has a pressure less than one percent that of Earth. To convert it into usable raw materials, it must first be efficiently and reliably captured and pressurized to reach the pressure and concentration required for subsequent processing. This initial step is the first link in the entire in-situ resource utilization technology chain for the Martian atmosphere, and its efficiency and reliability directly determine the success or failure of the entire system.

[0004] Previous literature and proposals for Mars compressors often referenced configurations from terrestrial compression systems, such as scroll compressors and piston compressors. However, the intake pressure of a Mars compressor differs from that of a typical terrestrial compressor by more than a hundred times. This results in a significant energy waste in internal gas recirculation during operation, limiting the performance of traditional compressors. Analysis reveals that Martian atmospheric capture is essentially a process of continuously extracting and compressing gas from a near-vacuum environment. Therefore, designing a high-performance Martian atmospheric capture and compression device should primarily reference designs from terrestrial vacuum systems, rather than compression systems. Consequently, developing an efficient, high-flow-rate atmospheric capture and pressurization device suitable for Mars requires innovation in existing technologies. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides a three-stage Martian surface atmosphere capture and pressurization device and control method, thereby solving the problem that traditional compressors cannot effectively capture and pressurize the Martian surface atmosphere.

[0006] To achieve the above objectives, the technical solution adopted by this invention is: a three-stage Martian surface atmosphere capture and pressurization device, mainly comprising: a Roots pump, a screw pump, a three-stage pump, liquid carbon dioxide, a carbon dioxide decompression chamber, an intermediate chamber, a high-pressure storage tank, a liquid verification bottle, a cryogenic experimental chamber, an automated measurement and control system, a check valve, a pressure relief valve, a manual ball valve, a motor, and a transmission belt; the automated measurement and control system includes an industrial computer, a pressure gauge, a thermometer, a flow meter, an electrically controlled needle valve, an electrically controlled ball valve, an electronic scale, a servo driver, an ammeter, and a voltmeter; The Roots pump body is a Roots pump head, including a Roots pump inlet and a Roots pump outlet, and is directly driven by a motor; the screw pump body is a screw pump head, including a screw pump inlet and a screw pump outlet, and is directly driven by a motor; the three-stage pump body is a three-stage pump head, including a three-stage pump inlet and a three-stage pump outlet, and is connected to a motor via a transmission belt; the three-stage pump head can be selected as either piston-type or scroll-type according to requirements. Piston pumps can provide higher pressure and have a wide applicable pressure range, while scroll pumps operate smoothly, have high efficiency near the design point, and have a long maintenance cycle.

[0007] Preferably, the three-stage Mars surface atmosphere capture and pressurization device has multiple connection methods and can be used for single-unit performance testing and series compression verification.

[0008] Preferably, when the third-stage Martian surface atmospheric capture and pressurization device is used for single-unit performance testing, a closed-loop measurement method is adopted to measure the power and efficiency of the Roots pump and screw pump under different flow rates and compression ratios. Liquid carbon dioxide is used as a gas source and connected to the carbon dioxide decompression chamber to simulate the inlet pressure. The inlet pressure is measured using a pressure gauge, and the gas supply is controlled by an electrically controlled needle valve to control the system pressure. The inlet of the Roots pump or the inlet of the screw pump is connected to the carbon dioxide decompression chamber, and a thermometer is set in front of the inlet to measure the inlet temperature. The exhaust port of the Roots pump or the screw pump... The exhaust port of the rod pump is connected to the intermediate chamber, and a thermometer is installed after the exhaust port to measure the exhaust temperature. The exhaust pressure is simulated using the intermediate chamber, and the exhaust pressure is measured using a pressure gauge. A loop is led out from the intermediate chamber and connected to the carbon dioxide decompression chamber. A flow meter is installed on the loop to measure the flow rate of the pump under test, and an electrically controlled needle valve is installed to control the pressure drop by adjusting the valve opening, thereby realizing the measurement of different compression ratio conditions. A branch is led out from the loop to connect to the vacuum pump, which is used to adjust the initial pressure of the system before the start of the test. A manual ball valve is installed in front of the vacuum pump to isolate the vacuum pump after the start of the test.

[0009] Preferably, when the three-stage Martian surface atmosphere capture and pressurization device is used for series compression verification, liquid carbon dioxide is used as the gas source and connected to the carbon dioxide decompression chamber to simulate the Martian atmospheric environment. The Roots pump inlet is connected to the carbon dioxide decompression chamber, the Roots pump outlet is connected to the screw pump inlet, and the screw pump outlet is connected to the intermediate chamber. The intermediate chamber is used to buffer the gas pressure and has a one-way valve connected to the atmosphere to keep the intermediate chamber pressure consistent with the atmospheric pressure. The three-stage pump inlet is connected to the buffer chamber, and the three-stage pump outlet is connected to the high-pressure storage tank. The high-pressure storage tank is equipped with a pressure relief valve to control the high-pressure storage tank from exceeding the safe pressure. The high-pressure storage tank is connected to the liquid verification bottle, and the pressure of the liquid verification bottle is controlled by a manual ball valve. The liquid verification bottle is placed in a low-temperature experimental chamber, the temperature of which is close to the average temperature of the Martian surface, to verify the phase state of the final product.

[0010] Preferably, when the three-stage Mars surface atmospheric capture and pressurization device is used for series compression verification, the automated measurement and control system is arranged as follows: an electrically controlled needle valve is arranged between the liquid carbon dioxide and the carbon dioxide decompression chamber to control the amount of supplemental gas to maintain the pressure inside the chamber; a pressure gauge is arranged on the carbon dioxide decompression chamber to measure the initial inlet pressure; a thermometer is installed before the Roots pump to measure the initial inlet temperature; a pressure gauge and a thermometer are arranged between the Roots pump and the screw pump to measure the intermediate pressure and intermediate temperature; a thermometer is arranged after the screw pump exhaust port to measure the screw pump exhaust temperature; a pressure gauge is installed on the intermediate chamber to measure the inlet pressure of the three-stage pump; and so on. A flow meter is installed at the junction of the compartment and the atmosphere via a check valve to measure the flow rate of the first two stages before the third-stage pump starts, and to assist in matching the flow rate of the third-stage pump with that of the first two stages after the third-stage pump starts. An electrically controlled ball valve is installed before the air inlet of the third-stage pump to close the air path of the third-stage pump when the first two stages are running. Thermometers are installed before the air inlet and after the air outlet of the third-stage pump to measure the inlet and outlet temperatures of the third-stage pump. A pressure gauge is installed on the high-pressure storage tank to measure the final pressure. An electronic scale is used to measure the mass change of the high-pressure storage tank to calculate the mass flow rate. The three motors used to drive the three pumps are equipped with servo drivers, ammeters, and voltmeters to adjust the motor speed and monitor the power.

[0011] Preferably, the program running on the industrial control computer mainly includes a data acquisition module, a human-machine interaction module, an automatic control module, a data processing module, and a safety and security module, which realizes status monitoring, operation control, parameter calculation, and safety assurance for the device.

[0012] A method for regulating a three-stage Mars surface atmosphere capture and pressurization device, based on the aforementioned three-stage Mars surface atmosphere capture and pressurization device, includes the following steps: S1: Single-unit performance testing and compression ratio control steps. Connect each device according to the single-unit test system design, measure the performance curves of the Roots pump and screw pump under different compression ratios, perform matching calculations on the optimal working range, and optimize the compression ratio distribution of the series compression system. S2: Series compression verification step. Connect each device according to the series compression verification system design. Use the automated measurement and control system to make the Roots pump and screw pump run at the optimal compression ratio obtained in step S1. Match the three-stage pump with the first two stages. After the whole set of devices reaches a stable operating state, measure its various performance parameters. S3: Product phase verification step. Keep the equipment running stably, draw a portion of the gas from the high-pressure storage tank to the liquid verification bottle and place it in the low-temperature test chamber. After some of the carbon dioxide condenses into liquid, shake the bottle to verify that the carbon dioxide can reach a liquid state in the Martian environment.

[0013] The beneficial effects of this invention are: 1. In response to the extremely low atmospheric density on the surface of Mars, an innovative three-stage series compression configuration of "Roots + screw + piston / vortex" is proposed. The first-stage Roots pump can achieve large-flow air intake and initial pressurization under near-vacuum pressure, the second-stage screw pump can achieve continuous gas delivery and pressurization, and the third-stage pump can further compress the gas to meet the final high-pressure requirements. It can simultaneously meet the requirements of high air intake and high compression ratio in the Martian environment. 2. By using liquid carbon dioxide as a gas source and electronically controlled needle valves for precise pressure regulation, a carbon dioxide decompression chamber can be used to simulate low atmospheric pressure or other pressure conditions on the Martian surface. This provides a ground-based experimental environment close to the Martian atmosphere with relatively low engineering difficulty, improving the accuracy of device performance control and effectively controlling costs. 3. It adopts a modular design, making the components easy to replace. By changing the connection method of the components, it can realize both single-machine testing and series testing functions. A single platform can complete all performance control and verification work, including single-machine selection testing, compression ratio allocation optimization, and series system integration testing. 4. An automated testing and control system is adopted. After setting key parameters, automatic testing can begin, avoiding the complexity and inaccuracy caused by manual adjustment in traditional testing systems. Attached Figure Description

[0014] Figure 1 This is a configuration diagram of a series test system for a three-stage Mars surface atmospheric capture and pressurization device.

[0015] Figure 2 This is a side view of a Roots pump and a schematic diagram of related components.

[0016] Figure 3 This is a side view of a screw pump and a schematic diagram of related components.

[0017] Figure 4 This is a side view of a three-stage pump and a schematic diagram of related components.

[0018] Figure 5 This is a configuration diagram of a single-unit test system for a Roots pump.

[0019] Figure 6 This is a configuration diagram of a single-unit test system for a screw pump.

[0020] Figure 7 This is a diagram of the components of an industrial computer automated measurement and control system.

[0021] Figure 8 This is a flowchart of a single-unit test and control procedure for a Roots pump.

[0022] Figure 9 This is a flowchart of a single-unit test and control procedure for a screw pump.

[0023] Figure 10 This is a flowchart of a series test control procedure.

[0024] The diagram shows: 1-Roots pump, 2-Screw pump, 3-Three-stage pump, 4-Liquid carbon dioxide, 5-Carbon dioxide decompression chamber, 6-Intermediate chamber, 7-High-pressure storage tank, 8-Liquid verification bottle, 9-Cryogenic test chamber, 10-Automatic measurement and control system, 11-Check valve, 12-Pressure relief valve, 13-Manual ball valve, 14-Motor, 15-Drive belt, 16-Vacuum pump, 100-Roots pump head, 1001-Roots pump inlet, 1002-Roots pump exhaust. Air inlet, 200-Screw pump head, 2001-Screw pump air inlet, 2002-Screw pump exhaust port, 300-Three-stage pump head, 3001-Three-stage pump air inlet, 3002-Three-stage pump exhaust port, 101-Industrial computer, 102-Pressure gauge, 103-Thermometer, 104-Flow meter, 105-Electrically controlled needle valve, 106-Electrically controlled ball valve, 107-Electronic scale, 108-Servo driver, 109-Ammeter, 1010-Voltmeter. Detailed Implementation

[0025] To better understand the technical content of this invention, the technical solution of this invention will be further described below with reference to the accompanying drawings.

[0026] like Figures 1 to 7 As shown, a three-stage Mars surface atmosphere capture and pressurization device mainly includes: Roots pump 1, screw pump 2, three-stage pump 3, liquid carbon dioxide 4, carbon dioxide decompression chamber 5, intermediate chamber 6, high-pressure storage tank 7, liquid verification bottle 8, cryogenic experimental chamber 9, automated measurement and control system 10, check valve 11, pressure relief valve 12, manual ball valve 13, motor 14, and transmission belt 15. The automated measurement and control system 10 includes an industrial computer 101, a pressure gauge 102, a thermometer 103, a flow meter 104, an electrically controlled needle valve 105, an electrically controlled ball valve 106, an electronic scale 107, a servo driver 108, an ammeter 109, and a voltmeter 1010. The main body of the Roots pump 1 is a Roots pump head 100, including a Roots pump inlet 1001 and a Roots pump outlet 1002, and is directly driven by a motor 14. The main body of the screw pump 2 is a screw pump head 200, including a screw pump inlet 2001 and a screw pump outlet 2002, and is directly driven by a motor 14. The main body of the three-stage pump 3 is a three-stage pump head 300, including a three-stage pump inlet 3001 and a three-stage pump outlet 3002, and is connected to the motor 14 via a transmission belt 15 to facilitate the replacement of three-stage pump heads 300 with different configurations.

[0027] The three-stage pump head 300 can be selected as either a piston pump or a scroll pump, depending on the requirements. Piston pumps have a higher single-stage compression ratio and can maintain a high volumetric efficiency in the high-pressure region, but their exhaust has pulsation, and their operational stability is weaker than that of scroll pumps. They also require more frequent maintenance during continuous operation, making them suitable for applications requiring higher pressure. Scroll pumps have a smooth, pulsation-free compression process, low vibration and noise during operation, and high reliability and lifespan. However, their compression ratio is limited by the scroll profile design, resulting in a lower single-stage pressure ratio compared to piston pumps. They are suitable for applications requiring stable operation and long-term maintenance-free operation. Both piston pumps and scroll pumps can be well matched with the backing pump to form a continuous compression covering the low-pressure to high-pressure region, meeting the needs of Martian atmospheric capture, compression, and liquefaction.

[0028] The three-stage Mars surface atmosphere capture and pressurization device has multiple connection methods and can be used for single-unit performance testing and series compression verification. Different test functions can be achieved simply by changing the connection method of each component.

[0029] When the three-stage Martian surface atmosphere capture and pressurization device is used for single-unit performance testing, a closed-loop measurement method is adopted. The single-unit test control method in the automatic control module of the industrial control computer 101 can be used to measure the power and efficiency of Roots pump 1 and screw pump 2 under different flow rates and compression ratios. Roots pump 1 and screw pump 2 can be regarded as low-pressure compression stages. The performance target is to compress the Martian atmosphere to the Earth's atmospheric pressure for further processing. Therefore, the main goal of single-unit performance testing is to obtain the optimal intermediate pressure when the inlet pressure of Roots pump 1 is fixed and the exhaust pressure of screw pump 2 is fixed. This connection method uses liquid carbon dioxide 4 as the gas source, connected to the carbon dioxide decompression chamber 5 to simulate the intake pressure. The intake pressure is measured using a pressure gauge 102, and the gas supply is controlled via an electrically controlled needle valve 105 to control the system pressure. The Roots pump inlet 1001 or the screw pump inlet 2001 is connected to the carbon dioxide decompression chamber 5, and a thermometer 103 is installed before the inlet to measure the intake temperature. The Roots pump exhaust port 1002 or the screw pump exhaust port 2002 is connected to the intermediate chamber 6, and a thermometer 103 is installed after the exhaust port to measure the exhaust temperature. The intermediate chamber 6 is used to simulate the exhaust pressure, and the pressure is controlled via a pressure gauge 102 to measure the intake pressure. Force gauge 102 measures the exhaust pressure; a loop is led out from intermediate chamber 6 and connected to carbon dioxide decompression chamber 5, so that the system reaches a closed-loop operation state. At this time, the gas return mass flow rate is consistent with the mass flow rate of the pump under test. A flow meter 104 is arranged on the loop to measure the flow rate of the pump under test. An electrically controlled needle valve 105 is arranged to control the pressure drop by the valve opening, so as to realize the measurement of different compression ratio conditions; a branch is led out from the loop to connect to vacuum pump 16, which is used to adjust the initial pressure of the system before the test begins. A manual ball valve 13 is arranged in front of vacuum pump 16 to isolate vacuum pump 16 after the test begins. During the test of Roots pump 1, the electrically controlled needle valve 105 connected to liquid carbon dioxide 4 and the electrically controlled needle valve 105 in the fully open circuit are first closed. The vacuum pump 16 is then used to manually pump the carbon dioxide decompression chamber 5 and intermediate chamber 6 to the predetermined inlet pressure, after which the manual ball valve 13 is closed. The maximum exhaust pressure and predetermined speed are set, and the test begins. At this time, the pressure in both the carbon dioxide decompression chamber 5 and intermediate chamber 6 is the inlet pressure. The electrically controlled needle valve 105 on the control circuit of the automated measurement and control system 10 gradually closes, causing the pressure in intermediate chamber 6 to gradually increase. Simultaneously, the electrically controlled needle valve 105 on liquid carbon dioxide 4 is controlled to replenish the system, keeping the pressure in the carbon dioxide decompression chamber 5 constant. The logic is that when the error is within an acceptable range, the needle valve opening remains unchanged; when the error exceeds the acceptable range, the opening of the electrically controlled needle valve 105 is increased or decreased according to the error value. During this process, pressure, flow rate, voltage, and current are automatically recorded and calculated, and performance curves are generated. During the test of screw pump 2, the electrically controlled needle valve 105 connected to liquid carbon dioxide 4 and the electrically controlled needle valve 105 in the fully open circuit are first closed. The vacuum pump 16 is then used to manually pump the carbon dioxide decompression chamber 5 and intermediate chamber 6 to the predetermined minimum inlet pressure, after which the manual ball valve 13 is closed. The exhaust pressure and predetermined speed are set, and the test begins. At this time, the pressures in both the carbon dioxide decompression chamber 5 and intermediate chamber 6 are at the minimum inlet pressure. The electrically controlled needle valve 105 on the control circuit of the automated measurement and control system 10 gradually closes, causing the pressure in intermediate chamber 6 to gradually rise to the predetermined exhaust pressure and remain constant. The logic is as follows: when the error is within an acceptable range, the opening of the electrically controlled needle valve 105 on the circuit remains unchanged; when the error exceeds the acceptable range, the opening of the electrically controlled needle valve 105 on the circuit is increased or decreased according to the error value. When the air pressure in the intermediate chamber 6 gradually rises to the predetermined exhaust pressure and remains unchanged, the electrically controlled needle valve 105 on the liquid carbon dioxide 4 is controlled to replenish the system air, so that the air pressure in the carbon dioxide decompression chamber 5 gradually rises from the lowest inlet pressure to the same as the exhaust pressure. During this process, the pressure, flow rate, voltage, and current are automatically recorded and calculated, and a performance curve is generated.

[0030] When the three-stage Martian surface atmosphere capture and pressurization device is used for series compression verification, the series test control method in the automatic control module of the industrial control computer 101 can be used to measure the performance data of the three-stage pumps working in series and verify the phase state of the final product. Liquid carbon dioxide 4 is used as a gas source and connected to the carbon dioxide decompression chamber 5 to simulate the Martian atmospheric environment. The Roots pump inlet 1001 is connected to the carbon dioxide decompression chamber 5, the Roots pump exhaust port 1002 is connected to the screw pump inlet 2001, and the screw pump exhaust port 2002 is connected to the intermediate chamber 6. Chamber 6 is used to buffer air pressure and has a one-way valve connected to the atmosphere to keep the pressure in intermediate chamber 6 consistent with atmospheric pressure. The inlet 3001 of the three-stage pump is connected to the buffer chamber, and the outlet 3002 of the three-stage pump is connected to the high-pressure storage tank 7. The high-pressure storage tank 7 is equipped with a pressure relief valve 12 to control the pressure of the high-pressure storage tank 7 from exceeding the safe pressure. The high-pressure storage tank 7 is connected to the liquid verification bottle 8, and the pressure of the liquid verification bottle 8 is controlled by a manual ball valve 13. The liquid verification bottle 8 is placed in a low-temperature test chamber 9, whose temperature is close to the average temperature of the Martian surface, and is used to verify the phase of the final product. The automated measurement and control system 10 is arranged as follows during the series compression verification: an electrically controlled needle valve 105 is arranged between liquid carbon dioxide 4 and carbon dioxide decompression chamber 5 to control the amount of supplemental gas to maintain the pressure inside the chamber; a pressure gauge 102 is arranged on carbon dioxide decompression chamber 5 to measure the initial inlet pressure; a thermometer 103 is installed before Roots pump 1 to measure the initial inlet temperature; a pressure gauge 102 and a thermometer 103 are arranged between Roots pump 1 and screw pump 2 to measure the intermediate pressure and intermediate temperature; a thermometer 103 is arranged after the screw pump exhaust port 2002 to measure the exhaust temperature of screw pump 2; a pressure gauge 102 is installed on intermediate chamber 6 to measure the inlet pressure of the third-stage pump 3; and intermediate chamber 6 is connected to the atmosphere via check valve 11. A flow meter 104 is used to measure the flow rate of the first two stages before the third-stage pump 3 is started, and to assist the third-stage pump 3 in matching the flow rate of the first two stages after it is started. An electrically controlled ball valve 106 is arranged in front of the air inlet 3001 of the third-stage pump to close the air path of the third-stage pump 3 when the first two stages are running. A thermometer 103 is arranged in front of the air inlet 3001 of the third-stage pump and after the exhaust port 3002 of the third-stage pump to measure the inlet and exhaust temperature of the third-stage pump 3. A pressure gauge 102 is installed on the high-pressure storage tank 7 to measure the final pressure. An electronic scale 107 is used to measure the mass change of the high-pressure storage tank 7 to calculate the mass flow rate. The three motors 14 used to drive the three pumps are equipped with a servo driver 108, an ammeter 109, and a voltmeter 1010 to adjust the speed of the motor 14 and monitor the power. During the tandem compression verification, the electrically controlled ball valve 106 and the electrically controlled needle valve 105 are first closed. The inlet pressure, intermediate pressure, and mass flow rate are set in the automated measurement and control system 10, and the test begins. The automated measurement and control system 10 controls the Roots pump 1 and screw pump 2 to operate according to preset conditions, and replenishes the system with gas by controlling the electrically controlled needle valve 105 on the liquid carbon dioxide 4 to keep the pressure inside the carbon dioxide decompression chamber 5 constant. The logic is that when the error is within an acceptable range, the opening of the electrically controlled needle valve 105 on the liquid carbon dioxide 4 remains unchanged; when the error exceeds the acceptable range, the opening of the electrically controlled needle valve 105 on the liquid carbon dioxide 4 is increased or decreased according to the error value. At this time, the airflow flows from the intermediate chamber 6 through the check valve... Valve 11 directs the flow to the atmosphere. The flow rate of the first two pump stages is measured by the flow meter 104 after the check valve 11. After the first two stages reach a stable operating state, the electric ball valve 106 is opened and the third pump 3 is started. The automatic measurement and control system 10 controls the speed of the third pump 3 so that the reading of the flow meter 104 after the check valve 11 is close to zero. The logic is that when the reading of the flow meter 104 after the check valve 11 is within an error range greater than 0, the speed of the third pump 3 remains unchanged. When the reading of the flow meter 104 after the check valve 11 exceeds the error range, the speed of the third pump 3 is increased or decreased according to the error value. At this time, the flow rate of the three pumps is matched and a stable operating state is reached, and relevant parameters can be measured and phase verification can be performed.

[0031] The program running on the industrial control computer 101 mainly includes a data acquisition module, a human-machine interaction module, an automatic control module, a data processing module, and a safety and protection module, realizing status monitoring, operation control, parameter calculation, and safety assurance for the device. The data acquisition module is used to read the pressure, flow, temperature, and power parameters of the equipment. The human-machine interaction module is used to set the testing purpose of the device at the software level, manually control the device's operating status, and display various parameters of the device in real time. The automatic control module uses a preset program to automatically control the device's operating status in single-machine or series testing. The data processing module can calculate the device's performance indicators and generate performance curves in real time based on the measured parameters. The safety and protection module can automatically alarm and terminate system operation in case of abnormal temperature or power.

[0032] A method for regulating a three-stage Mars surface atmosphere capture and pressurization device includes the following steps: S1: Single-unit performance test and compression ratio control steps: Connect each device according to the single-unit test system design, close the electric control needle valve 105 of liquid carbon dioxide 4, fully open the electric control needle valve 105 on the circuit, start the vacuum pump 16 to adjust the pressure of carbon dioxide decompression chamber 5 and intermediate chamber 6 to the preset initial inlet pressure, and then close the manual ball valve 13 to isolate the vacuum pump 16 from the system. The target pressure and mass flow rate are set by the automated measurement and control system 10, the test program is started, and the industrial control computer 101 automatically controls the system to perform the test according to the preset parameters, collects and records the pressure, flow rate, voltage and current data under different working conditions, calculates the performance index of the pump under test under different compression ratios, and automatically plots the performance curve. By analyzing the curves, the optimal intermediate pressure value and the corresponding optimal operating conditions under given intake pressure and final exhaust pressure are determined, providing basic data for series operation. S2: Series compression verification steps. Connect each device according to the series compression verification system design. Set the inlet pressure and mass flow rate through the automated measurement and control system 10. Close the electrically controlled ball valve 106 before the inlet 3001 of the three-stage pump. Start the Roots pump 1 and the screw pump 2. Start the test program. The system automatically controls the electrically controlled needle valve 105 of the liquid carbon dioxide 4 to replenish the gas and maintain the constant pressure of the carbon dioxide decompression chamber 5. At this time, the airflow enters the intermediate chamber 6 after passing through the first two pumps and is discharged to the atmosphere through the check valve 11 of the intermediate chamber 6. The flow meter 104 after the check valve 11 monitors and records the stable flow rate of the first two pumps. After the first two stages have stabilized, open the electrically controlled ball valve 106 before the air inlet 3001 of the third-stage pump and start the third-stage pump 3. The system automatically adjusts the speed of the third-stage pump 3 according to the pressure of the intermediate chamber 6 and the reading of the flow meter 104 after the check valve 11, so that the reading of the flow meter 104 after the check valve 11 approaches zero, indicating that all the gas discharged by the Roots pump 1 and the screw pump 2 is sucked into the third-stage pump 3 and the third-stage pump achieves flow matching. At this time, the automated measurement and control system 10 collects and records the pressure, temperature, flow rate and power data of the three motors 14 at each key node of the entire system to evaluate the overall performance of the system. S3: Product phase verification step. This step aims to verify the phase of the carbon dioxide product after three-stage pressurization to confirm whether it has reached the expected liquid state to meet the requirements of subsequent storage or utilization. After the series compression verification system is running stably, excess gas is discharged from the pressure relief valve 12 of the high-pressure storage tank 7. The outlet of the high-pressure storage tank 7 is connected to the liquid verification bottle 8 placed in the low-temperature test chamber 9 through the manual ball valve 13. The temperature of the low-temperature test chamber 9 is set to be close to the average temperature of the Martian surface. The manual ball valve 13 between the high-pressure storage tank 7 and the liquid verification bottle 8 is slowly opened to allow the high-pressure carbon dioxide after three stages of pressurization to enter the liquid verification bottle 8. After condensation for a period of time, the bottle is taken out and shaken to verify whether the carbon dioxide has liquefied.

[0033] This invention innovatively proposes a three-stage tandem compression configuration of "Roots + Screw + Piston / Scroll" to address the extremely low atmospheric density on the Martian surface. The first-stage Roots pump 1 can achieve high-flow-rate air intake and initial pressurization under near-vacuum pressure. The second-stage screw pump 2 can achieve continuous gas delivery and pressurization. The third-stage pump 3 can further compress the gas to meet the final high-pressure requirements. It can simultaneously meet the requirements of high air intake and high compression ratio in the Martian environment. Moreover, since the Roots pump 1 and screw pump 2 adopt a dry design without internal contact, the third-stage pump 3 can also adopt an oil-free design, which can achieve clean and oil-free gas in the system. It is suitable for the field of in-situ utilization of the Martian atmosphere where the gas cleanliness requirements are stringent, and avoids the additional uncertainties brought to the Martian mission by the lubrication system. By using liquid carbon dioxide 4 as a gas source and the electrically controlled needle valve 105 for precise pressure regulation, the carbon dioxide decompression chamber 5 can be used to simulate the low pressure or other pressure conditions on the surface of Mars. This provides a ground experimental environment close to the Martian atmosphere with relatively low engineering difficulty, improves the accuracy of device performance regulation, and effectively controls costs. With a modular design, the components are easy to replace, and by changing the connection method of the components, both single-machine testing and series testing can be achieved. A single platform can complete all performance control and verification work, including single-machine selection testing, compression ratio allocation optimization, and series system integration testing. The automated measurement and control system 10 can be used to start automatic testing after setting key parameters, avoiding the complexity and inaccuracy caused by manual adjustment in traditional testing systems;

[0034] The above description is only used to further illustrate the technical content of the present invention so that readers can understand it more easily, but it does not mean that the implementation of the present invention is limited to this. Any technical extension or re-creation made in accordance with the present invention is protected by the present invention.

Claims

1. A three-stage Martian surface atmosphere capture and pressurization device, comprising a Roots pump (1), a screw pump (2), a three-stage pump (3), liquid carbon dioxide (4), a carbon dioxide decompression chamber (5), an intermediate chamber (6), a high-pressure storage tank (7), a liquid verification bottle (8), a cryogenic experimental chamber (9), an automated measurement and control system (10), a check valve (11), a pressure relief valve (12), a manual ball valve (13), a motor (14), and a transmission belt (15), characterized in that: The Roots pump (1) is capable of large-flow air intake and initial pressurization under the Martian atmospheric pressure of approximately 0.7 kPa absolute pressure, initially raising the air pressure to about 8 kPa; the main body of the Roots pump (1) is the Roots pump head (100), which includes the Roots pump inlet (1001) and the Roots pump exhaust port (1002), and the Roots pump head (100) is directly driven by the motor (14); The screw pump (2) can achieve continuous gas delivery and pressurization in the medium pressure stage. The screw pump inlet (2001) is connected to the Roots pump outlet (1002). The inlet pressure is about 8 kPa. Under the condition that the mass flow rate matches the Roots pump (1), the gas can be further compressed to about 100 kPa, so that the Martian atmosphere is pressurized to close to the Earth's atmospheric pressure. The main body of the screw pump (2) is the screw pump head (200). The screw pump head (200) includes the screw pump inlet (2001) and the screw pump outlet (2002). The screw pump head (200) is directly driven by the motor (14). The three-stage pump (3) can further compress the gas to more than 800 kPa so that it can be liquefied at a Martian temperature of about -50°C. The main body of the three-stage pump (3) is a three-stage pump head (300), which includes a three-stage pump inlet (3001) and a three-stage pump outlet (3002). It is connected to a motor (14) via a transmission belt (15) so as to facilitate the replacement of three-stage pump heads (300) with different configurations. The three-stage pump head (300) can be selected as either piston or scroll pump as required. Piston pumps have a higher single-stage compression ratio and can maintain a higher volumetric efficiency in the high-pressure area, but their exhaust has pulses, and their operation stability is weaker than that of scroll pumps. Moreover, they require more frequent maintenance when running continuously, making them suitable for working conditions that require higher pressure. Scroll pumps have a smooth compression process without pulsation, low vibration and low noise during operation, and have high reliability and lifespan. However, their compression ratio is limited by the scroll profile design, and their single-stage pressure is lower than that of piston pumps, making them suitable for working conditions that require stable operation and long-term maintenance-free operation. By using Roots pump (1), screw pump (2), and three-stage pump (3) in series, the performance advantages of the three types of compressors can be brought into play at different pressure stages, thereby simultaneously meeting the requirements of high intake volume and high compression ratio in the Martian environment.

2. The three-stage Mars surface atmosphere capture and pressurization device according to claim 1, characterized in that: The three-stage Mars surface atmosphere capture and pressurization device achieves single-unit performance testing or series compression verification by changing the connection method of each component. The purpose of single-unit performance testing is to measure the performance curves of each pump under different operating conditions so as to optimize and control the compression ratio distribution during series operation. The purpose of series compression verification is to measure the performance parameters of the series compression system during operation and verify the phase state of the final product.

3. The three-stage Mars surface atmosphere capture and pressurization device according to claim 1, characterized in that: When the three-stage Mars surface atmosphere capture and pressurization device is used for single-machine performance testing, a closed-loop measurement method is adopted. The single-machine test control method in the automatic control module of the industrial control computer (101) can be used to measure the power and efficiency of the Roots pump (1) and the screw pump (2) under different flow rates and compression ratios. The Roots pump (1) and the screw pump (2) can be regarded as low-pressure compression stages. The performance goal is to compress the Martian atmosphere to the Earth's atmospheric pressure for further processing. Therefore, the main goal of the single-machine performance test is to obtain the optimal intermediate pressure when the inlet pressure of the Roots pump (1) is fixed and the exhaust pressure of the screw pump (2) is fixed. This connection method uses liquid carbon dioxide (4) as the gas source, which is connected to the carbon dioxide decompression chamber (5) to simulate the intake pressure. The intake pressure is measured using a pressure gauge (102), and the gas supply is controlled by an electrically controlled needle valve (105) to control the system pressure. The Roots pump inlet (1001) or screw pump inlet (2001) is connected to the carbon dioxide decompression chamber (5), and a thermometer (103) is installed in front of the inlet to measure the intake temperature. The Roots pump exhaust port (1002) or screw pump exhaust port (2002) is connected to the intermediate chamber (6), and a thermometer (103) is installed after the exhaust port to measure the exhaust temperature. The intermediate chamber (6) is used to simulate the exhaust pressure. The exhaust pressure is measured using a pressure gauge (102); a loop is drawn from the intermediate chamber (6) and connected to the carbon dioxide decompression chamber (5) so that the system can reach a closed-loop operation state. At this time, the mass flow rate of the gas return is consistent with the mass flow rate of the pump under test. A flow meter (104) is arranged on the loop to measure the flow rate of the pump under test. An electrically controlled needle valve (105) is arranged to control the pressure drop by the valve opening so as to realize the measurement of different compression ratio conditions. A branch is drawn from the loop to connect to the vacuum pump (16) to adjust the initial pressure of the system before the test begins. A manual ball valve (13) is arranged in front of the vacuum pump (16) to isolate the vacuum pump (16) after the test begins.

4. A three-stage Mars surface atmosphere capture and pressurization device according to claim 1, characterized in that: When the three-stage Mars surface atmosphere capture and pressurization device is used for series compression verification, the Roots pump inlet (1001) is connected to the carbon dioxide decompression chamber (5), the Roots pump exhaust port (1002) is connected to the screw pump inlet (2001), the screw pump exhaust port (2002) is connected to the intermediate chamber (6), the three-stage pump inlet (3001) is connected to the intermediate chamber (6), the three-stage pump exhaust port (3002) is connected to the high-pressure storage tank (7), the high-pressure storage tank (7) is connected to the liquid verification bottle (8) placed in the low-temperature experimental chamber (9) through a manual ball valve (13), and a pressure relief valve (12) is installed on the high-pressure storage tank (7). In this connection method, an electrically controlled needle valve (105) is installed between the liquid carbon dioxide (4) and the carbon dioxide decompression chamber (5), a pressure gauge (102) is installed on the carbon dioxide decompression chamber (5), a thermometer (103) is installed in front of the Roots pump (1), a pressure gauge (102) and a thermometer (103) are installed between the Roots pump (1) and the screw pump (2), a pressure gauge (102) is installed on the intermediate chamber (6), a flow meter (104) is installed at the connection between the intermediate chamber (6) and the atmosphere through the check valve (11), an electrically controlled ball valve (106) is installed in front of the inlet (3001) of the third-stage pump, a thermometer (103) is installed in front of the inlet (3001) of the third-stage pump and after the outlet (3002) of the third-stage pump, a pressure gauge (102) is installed on the high-pressure storage tank (7), and the motor (14) is equipped with a servo driver (108), an ammeter (109), and a voltmeter (1010).

5. A three-stage Mars surface atmosphere capture and pressurization device according to claim 1, characterized in that: The automated measurement and control system (10) includes an industrial computer (101), a pressure gauge (102), a thermometer (103), a flow meter (104), an electrically controlled needle valve (105), an electrically controlled ball valve (106), an electronic scale (107), a servo driver (108), an ammeter (109), and a voltmeter (1010). It can collect and calculate parameters such as pressure, temperature, flow rate, speed, and power at each node of the device, and automatically control the gas pressure in the carbon dioxide decompression chamber (5) and the speed of the three-stage pump (3). The program running on the industrial control computer (101) includes a data acquisition module, a human-machine interaction module, an automatic control module, a data processing module, and a safety protection module, which realizes status monitoring, operation control, parameter calculation, and safety assurance for the device. The data acquisition module is used to read the pressure, flow, temperature, and power parameters of the device. The human-machine interaction module is used to set the test purpose of the device at the software level, manually control the operation status of the device, and display the various parameters of the device in real time. The automatic control module uses a preset program to realize automatic control of the device's operation status in single-machine testing or series testing. It can control the system pressure and operation status by adjusting the opening of the electrically controlled needle valve (105) and the electrically controlled ball valve (106), and match the flow rate of each level by adjusting the speed of the motor (14). The data processing module can calculate the performance indicators of the device and generate performance curves in real time based on the measured parameters. The safety protection module can automatically alarm and terminate the system operation when the temperature or power is abnormal.

6. A method for controlling a three-stage Mars surface atmosphere trapping and pressurization device, based on the aforementioned three-stage Mars surface atmosphere trapping and pressurization device, characterized in that... Includes the following steps: S1: Single-unit performance test and compression ratio control steps: Connect each device according to the single-unit test system design, close the electric control needle valve (105) of liquid carbon dioxide (4), fully open the electric control needle valve (105) on the circuit, start the vacuum pump (16) to adjust the pressure of the carbon dioxide decompression chamber (5) and the intermediate chamber (6) to the preset initial inlet pressure, and then close the manual ball valve (13) to isolate the vacuum pump (16) from the system; The target pressure and mass flow rate are set by the automated measurement and control system (10), the test program is started, the industrial control computer (101) automatically controls the system to perform the test according to the preset parameters, collects and records the pressure, flow rate, voltage and current data under different working conditions, calculates the performance index of the pump under test under different compression ratios, and automatically draws the performance curve. By analyzing the curves, the optimal intermediate pressure value and the corresponding optimal operating conditions under given intake pressure and final exhaust pressure are determined, providing basic data for series operation. S2: Series compression verification steps. Connect each device according to the design of the series compression verification system. Set the inlet pressure and mass flow rate through the automated measurement and control system (10). Close the electric ball valve (106) before the inlet (3001) of the three-stage pump. Start the Roots pump (1) and the screw pump (2). Start the test program. The system automatically controls the electric needle valve (105) of the liquid carbon dioxide (4) to replenish the gas and maintain the constant pressure of the carbon dioxide decompression chamber (5). At this time, the airflow enters the intermediate chamber (6) after passing through the first two pumps and is discharged to the atmosphere through the check valve (11) of the intermediate chamber (6). The flow meter (104) after the check valve (11) monitors and records the stable flow rate of the first two pumps. After the first two stages have stabilized, open the electric ball valve (106) in front of the air inlet (3001) of the third stage pump and start the third stage pump (3). The system automatically adjusts the speed of the third stage pump (3) according to the pressure of the intermediate chamber (6) and the reading of the flow meter (104) after the check valve (11), so that the reading of the flow meter (104) after the check valve (11) approaches zero, indicating that all the gas discharged by the Roots pump (1) and the screw pump (2) is sucked into the third stage pump (3). The third stage pump has achieved flow matching. At this time, the automated measurement and control system (10) collects and records the pressure, temperature, flow rate and power data of the three motors (14) at each key node of the entire system to evaluate the overall performance of the system. S3: Product phase verification step. This step aims to verify the phase of the carbon dioxide product after three-stage pressurization to confirm whether it has reached the expected liquid state to meet the requirements of subsequent storage or utilization. After the series compression verification system is running stably, excess gas is discharged from the pressure relief valve (12) of the high-pressure storage tank (7). The outlet of the high-pressure storage tank (7) is connected to the liquid verification bottle (8) placed in the low-temperature test chamber (9) through the manual ball valve (13). The temperature of the low-temperature test chamber (9) is set to be close to the average temperature of the surface of Mars. The manual ball valve (13) between the high-pressure storage tank (7) and the liquid verification bottle (8) is slowly opened to allow the high-pressure carbon dioxide after three-stage pressurization to enter the liquid verification bottle (8). After condensation for a period of time, it is taken out and shaken to verify whether the carbon dioxide has liquefied.

7. A three-stage Mars surface atmosphere capture and pressurization device according to claim 6, characterized in that: When performing a single-unit performance test on the Roots pump (1), first close the electrically controlled needle valve (105) connected to the liquid carbon dioxide (4) and the electrically controlled needle valve (105) in the fully open circuit. Then, use the vacuum pump (16) to manually pump the carbon dioxide decompression chamber (5) and the intermediate chamber (6) to the predetermined inlet pressure and close the manual ball valve (13). Set the maximum exhaust pressure and the predetermined speed and start the test. At this time, the pressure of the carbon dioxide decompression chamber (5) and the intermediate chamber (6) are both the inlet pressure. The electrically controlled needle valve (105) on the control circuit of the automated measurement and control system (10) gradually closes, so that the air pressure in the intermediate chamber (6) gradually increases. At the same time, the electrically controlled needle valve (105) on the liquid carbon dioxide (4) is controlled to replenish the system so that the air pressure in the carbon dioxide decompression chamber (5) remains unchanged. The logic is that when the error is within the acceptable range, the needle valve opening remains unchanged. When the error is greater than the acceptable range, the opening of the electrically controlled needle valve (105) is increased or decreased according to the error value. During this process, the pressure, flow rate, voltage and current are automatically recorded and calculated, and a performance curve is generated.

8. A three-stage Mars surface atmosphere capture and pressurization device according to claim 6, characterized in that: When performing a single-unit performance test on the screw pump (2), first close the electrically controlled needle valve (105) connected to the liquid carbon dioxide (4) and the electrically controlled needle valve (105) in the fully open circuit. Then, use the vacuum pump (16) to manually pump the carbon dioxide decompression chamber (5) and the intermediate chamber (6) to the predetermined minimum inlet pressure, and then close the manual ball valve (13). Set the exhaust pressure and the predetermined speed and start the test. At this time, the pressure of the carbon dioxide decompression chamber (5) and the intermediate chamber (6) are both at the minimum inlet pressure. The electrically controlled needle valve (105) on the control circuit of the automated measurement and control system (10) gradually closes, so that the air pressure in the intermediate chamber (6) gradually increases to the predetermined pressure. The exhaust pressure remains constant. The logic is that when the error is within an acceptable range, the opening of the electrically controlled needle valve (105) on the circuit remains constant. When the error is greater than the acceptable range, the opening of the electrically controlled needle valve (105) on the circuit is increased or decreased according to the error value. When the air pressure in the intermediate chamber (6) gradually rises to the predetermined exhaust pressure and remains constant, the electrically controlled needle valve (105) on the liquid carbon dioxide (4) is controlled to replenish the system air, so that the air pressure in the carbon dioxide decompression chamber (5) gradually rises from the lowest inlet pressure to the same as the exhaust pressure. During this process, the pressure, flow rate, voltage, and current are automatically recorded and calculated, and a performance curve is generated.

9. A three-stage Mars surface atmosphere capture and pressurization device according to claim 6, characterized in that: When performing series compression verification, first close the electrically controlled ball valve (106) and the electrically controlled needle valve (105). Set the inlet pressure, intermediate pressure, and mass flow rate in the automated measurement and control system (10) and start the test. The automated measurement and control system (10) controls the Roots pump (1) and screw pump (2) to operate according to the preset working conditions, and replenishes the system with gas by controlling the electrically controlled needle valve (105) on the liquid carbon dioxide (4) to keep the gas pressure in the carbon dioxide decompression chamber (5) constant. The logic is that when the error is within the acceptable range, the opening of the electrically controlled needle valve (105) on the liquid carbon dioxide (4) remains unchanged. When the error is greater than the acceptable range, the opening of the electrically controlled needle valve (105) on the liquid carbon dioxide (4) is increased or decreased according to the error value. At this time, the airflow flows from the intermediate chamber (6) through the stop The return valve (11) flows to the atmosphere. The flow rate of the first two pumps is measured by the flow meter (104) after the check valve (11). After the first two pumps reach a stable operating state, the electric ball valve (106) is opened and the third pump (3) is started. The speed of the third pump (3) is controlled by the automatic measurement and control system (10) so that the reading of the flow meter (104) after the check valve (11) is close to zero. The logic is that when the reading of the flow meter (104) after the check valve (11) is within an error range greater than 0, the speed of the third pump (3) remains unchanged. When the reading of the flow meter (104) after the check valve (11) exceeds the error range, the speed of the third pump (3) is increased or decreased according to the error value. At this time, the flow rate of the third pump is matched and reaches a stable operating state, and relevant parameters can be measured and phase verification can be performed.

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