CN113899520B - Carbon dioxide component control system of Mars wind tunnel and control method thereof - Google Patents
Carbon dioxide component control system of Mars wind tunnel and control method thereof Download PDFInfo
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- CN113899520B CN113899520B CN202111066769.XA CN202111066769A CN113899520B CN 113899520 B CN113899520 B CN 113899520B CN 202111066769 A CN202111066769 A CN 202111066769A CN 113899520 B CN113899520 B CN 113899520B
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- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M9/00—Aerodynamic testing; Arrangements in or on wind tunnels
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- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M9/00—Aerodynamic testing; Arrangements in or on wind tunnels
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Abstract
The invention discloses aCarbon dioxide component control system of Mars wind tunnel and control method thereof, wherein the control system comprises CO 2 Concentration measurement system, CO 2 Gas source system, vacuum pumping system and absolute pressure sensor, CO 2 Concentration measurement system, vacuum pumping system and CO 2 The gas source system and the absolute pressure sensor are respectively communicated with the Mars cabin, and CO is 2 The air source system provides stable CO for the Mars wind tunnel 2 Power gas source, CO 2 The concentration measuring system comprises a carbon dioxide measuring flange, a gas return end, a sampling end pneumatic pilot valve, an air pump, a flowmeter and a carbon dioxide sensor. The control method detects the gas pressure in the Mars cabin through the absolute pressure sensor, further controls the working time sequence of the vacuum pumping system and the measuring system, can effectively realize that the concentration of carbon dioxide in the Mars cabin meets the test requirement during the test, and cannot be influenced by vacuum low-pressure, low-temperature and sand-dust tests. The invention has simple structure and convenient maintenance.
Description
Technical Field
The invention belongs to the technical field of simulation of a Mars test chamber, and particularly relates to a carbon dioxide component control system of a Mars wind tunnel and a control method thereof.
Background
The Mars wind tunnel can not be opened to simulate the testing chamber of the Mars atmospheric environment, and the testing chamber is used for simulating the air pressure, the gas composition, the temperature and the like on the surface of a Mars meter. The atmosphere surrounding the spark is very thin, and the main component of the surrounding atmosphere is carbon dioxide (CO) 2 About 95.3% by weight), the atmosphere in the test chamber is generally maintained at an absolute pressure of up to 100Pa (about 0.1% of the standard atmospheric pressure), and the chamber is filled during the testCO required for simulating Mars atmosphere 2 Gas, CO 2 Gas concentrations of 97% are typically required to effectively simulate gas composition.
To make CO in the test process 2 The gas concentration of (A) is required, and CO is required to be used 2 Concentration sensor to measure CO 2 But low gas pressure, low temperature and sand dust will be to CO during the test 2 Concentration sensor with adverse effect, using conventional CO 2 Measurement sensor or measurement method, not only can not obtain accurate CO 2 Concentration value, even of CO 2 Failure of the concentration sensor probe characteristics, resulting in internal blockage of the probe and damage to the CO 2 A concentration sensor.
Disclosure of Invention
Therefore, based on the defects, the invention provides the carbon dioxide component control system of the Mars wind tunnel, which can solve the problems of CO in the Mars wind tunnel under the low air pressure, low temperature and sand dust environment 2 The problem of component implementation.
In order to solve the technical problems, the invention adopts the technical scheme that: a carbon dioxide composition control system for a Mars wind tunnel comprises CO 2 Concentration measurement system, CO 2 Gas source system, vacuum pumping system and absolute pressure sensor, wherein the CO is 2 Concentration measurement system, vacuum pumping system and CO 2 The gas source system and the absolute pressure sensor are respectively communicated with the Mars cabin, and the CO is 2 The air source system provides stable CO for the Mars wind tunnel in the Mars cabin 2 A power gas source; said CO 2 The concentration measurement system comprises a carbon dioxide measurement flange, a sampling end pneumatic pilot valve, an air suction pump, a flowmeter, a carbon dioxide sensor and a return air end pneumatic pilot valve, wherein the carbon dioxide measurement flange is positioned on the outer wall of a Mars cabin and is fixedly connected with the outer wall, a sampling air inlet pipe and a sampling return air pipe are arranged on the carbon dioxide measurement flange and are respectively communicated with the inside of the Mars cabin, the sampling air inlet pipe is connected with the sampling end pneumatic pilot valve, the sampling end pneumatic pilot valve is connected with the air suction pump, the air suction pump is connected with the flowmeter, the flowmeter is connected with the carbon dioxide sensor, and the carbon dioxide sensor is connected with the return air end pneumatic pilot valveAnd the air return end pneumatic pilot valve is connected with the sampling air return pipe.
Further, the CO2 gas source system comprises a carbon dioxide gas inlet flange, a carbon dioxide gas inlet pipeline and a carbon dioxide gas source device, the carbon dioxide gas inlet flange is located on the outer wall of the Mars cabin and fixedly connected with the outer wall of the Mars cabin, one end of the carbon dioxide gas inlet pipeline is communicated with an ejector of the Mars wind tunnel through the carbon dioxide gas inlet flange, and the other end of the carbon dioxide gas inlet pipeline is communicated with the carbon dioxide gas source device.
Furthermore, the vacuum pumping system comprises an air pumping flange, a vacuum air pumping pipeline and a vacuum pumping device, the air pumping flange is located on the outer wall of the Mars cabin and is fixedly connected with the outer wall, one end of the vacuum air pumping pipeline is communicated with the Mars cabin through the air pumping flange, and the other end of the vacuum air pumping pipeline is communicated with the vacuum pumping device.
Another objective of the present invention is to provide a method for controlling carbon dioxide content in a Mars wind tunnel by using the above carbon dioxide content control system, comprising the following steps:
first step, CO is turned off 2 Concentration measurement system and CO 2 The air source system starts the vacuumizing system, monitors an absolute pressure sensor in the Mars cabin and vacuumizes the Mars cabin;
second, the vacuum-pumping system is turned off and CO is turned on 2 Gas source system for supplying gaseous CO 2 Injecting into Mars cabin, monitoring absolute pressure sensor, and closing CO when pressure in cabin reaches standard atmospheric pressure 2 A gas source system;
third, opening CO 2 Concentration measurement system: firstly opening a sampling end pneumatic pilot valve and a gas return end pneumatic pilot valve, then starting an air pump, and measuring the stable CO by a carbon dioxide sensor 2 Concentration value of (A), CO 2 After the concentration measurement is finished, the air pump is firstly closed, then the sampling end pneumatic pilot valve and the air return end pneumatic pilot valve are closed, and CO is finished 2 The concentration measurement of (2);
step four, if CO 2 Repeating the first to third steps if the concentration of (C) does not meet the test requirement;
step five, meeting the test requirementsCO of 2 After the concentration, a vacuumizing system is started, an absolute pressure sensor on the Mars cabin is monitored, and the absolute pressure required by the test is pumped.
The invention has the advantages that: the method for realizing the carbon dioxide component in the invention is simple, and the CO used by the method 2 The concentration sensor is a conventional sensor, does not need special protection, and detects the gas pressure in the Mars cabin through an absolute pressure sensor so as to control the vacuum-pumping system and CO 2 The working time sequence of the concentration measurement system can effectively meet the test requirement of the carbon dioxide concentration in the Mars cabin during the test, and is not influenced by vacuum low air pressure, low temperature and sand dust tests. In addition, a sampling measurement air pipe and an air return pipe are arranged, so that the problem of emission of carbon dioxide is avoided, and the stability during measurement is further improved. The invention has simple structure, convenient maintenance and obvious effect and is suitable for popularization and use.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the description of the embodiments or the prior art will be briefly introduced below, and the drawings in the following description are only some embodiments of the present invention, and other corresponding examples can be actually evolved.
FIG. 1 is a schematic block diagram of a carbon dioxide composition control system for a Mars wind tunnel.
In the figure: 1. the Mars cabin, 2, the Mars wind tunnel, 3, carbon dioxide measure the flange, 4, the sampling intake pipe, 5, the pneumatic pilot valve of sampling end, 6, the aspiration pump, 7, the flowmeter, 8, the carbon dioxide sensor, 9, the pneumatic pilot valve of return air end, 10, the flange of bleeding, 11, vacuum air bleed pipeline, 12, evacuating device, 13, the carbon dioxide air intake flange, 14, the carbon dioxide air supply unit, 15, the carbon dioxide air intake pipeline, 16, the ejector, 17, the absolute pressure sensor, 18, the sampling return air pipe.
Detailed Description
The invention is explained in detail below with reference to the drawings and examples. So that the advantages and features of the invention may be more readily understood by those skilled in the art, and the scope of the invention may be more clearly and clearly defined. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
Example 1
Referring to FIG. 1, a carbon dioxide composition control system for a Mars wind tunnel includes CO 2 Concentration measurement system, CO 2 Air supply system, vacuum pumping system and absolute pressure sensor, its characterized in that: said CO 2 Concentration measurement system, vacuum pumping system and CO 2 The gas source system and the absolute pressure sensor are respectively communicated with the Mars cabin, and the CO is 2 The air source system provides stable CO for the Mars wind tunnel in the Mars cabin 2 A power gas source;
the CO is 2 The concentration measurement system comprises a carbon dioxide measurement flange 3, a sampling end pneumatic pilot valve 5, an air suction pump 6, a flowmeter 7, a carbon dioxide sensor 8 and a gas return end pneumatic pilot valve 9, wherein the carbon dioxide measurement flange is located on the outer wall of a mars cabin and is fixedly connected with the outer wall, a sampling air inlet pipe 4 and a sampling gas return pipe 18 are arranged on the carbon dioxide measurement flange 3 and are respectively communicated with the inside of the mars cabin 1, the sampling air inlet pipe 4 is connected with the sampling end pneumatic pilot valve 5, the sampling end pneumatic pilot valve 5 is connected with the air suction pump 6, the air suction pump 6 is connected with the flowmeter 7, the flowmeter 7 is connected with the carbon dioxide sensor 8, the carbon dioxide sensor 8 is connected with the gas return end pneumatic pilot valve 9, and the gas return end pneumatic pilot valve 9 is connected with the sampling gas return pipe 18. When in measurement, the sampling end pneumatic pilot valve 5 and the air return end pneumatic pilot valve 9 are opened, the gas in the Mars cabin 1 is pumped out through the air pump 6, the flow meter 7 on the measuring gas pipe 4 can detect the gas flow, and the carbon dioxide sensor 8 can measure the CO after sampling 2 The gas concentration.
The CO2 gas source system comprises a carbon dioxide gas inlet flange 13, a carbon dioxide gas inlet pipeline 15 and a carbon dioxide gas source 14 device, wherein the carbon dioxide gas inlet flange 13 is positioned on the outer wall of the Mars cabin 1 and is fixedly connected with the Mars cabin, one end of the carbon dioxide gas inlet pipeline 15 is communicated with an ejector 16 of a Mars wind tunnel through the carbon dioxide gas inlet flange 13, the other end of the carbon dioxide gas inlet pipeline 15 is communicated with the carbon dioxide gas source device 14, and gaseous CO is supplied to the Mars wind tunnel 2 Injected into the Mars wind tunnel 2, not only can inject pure CO into the Mars cabin 1 2 And the gas can also provide a stable power gas source for the Mars wind tunnel 2 during the test.
The carbon dioxide component control method of the Mars wind tunnel is provided by the carbon dioxide component control system, and comprises the following steps:
first step, CO is turned off 2 The concentration measuring system (namely closing the sampling end pneumatic pilot valve 5, the air pump 6 and the air return end pneumatic pilot valve 9) closes the CO 2 And the air source system starts the vacuumizing system, monitors the absolute pressure sensor 17 on the Mars cabin, and the lowest absolute pressure which can be reached by vacuumizing the Mars cabin in the embodiment is 100Pa.
Second, the vacuum-pumping system is turned off and CO is turned on 2 Gas source system for supplying gaseous CO 2 Injecting into Mars cabin 1, monitoring absolute pressure sensor 17, and closing CO when pressure in the cabin reaches standard atmospheric pressure 2 And (3) an air source system.
Third step, opening CO 2 The concentration measuring system, namely, the sampling end pneumatic pilot valve 5 and the air return end pneumatic pilot valve 9 are firstly opened, the air pump 6 is then started, and the carbon dioxide sensor 8 measures CO 2 The concentration value of (1), the concentration value (usually, the value of stable data in continuous 5 s) of the measured data, CO 2 After the concentration measurement is finished, the air pump 6 is firstly closed, then the sampling end pneumatic pilot valve 5 and the air return end pneumatic pilot valve 9 are closed, and CO is finished 2 The concentration of (2).
Step four, if CO 2 Does not reach the test requirements (generally 97%), and the first to third steps are repeated.
Step five, CO meeting the test requirements 2 After the concentration, the vacuum pumping system is started, the absolute pressure sensor 17 on the Mars cabin 1 is monitored, and the absolute pressure required by the test is pumped.
Example 2
The pressure of the Mars cabin during the test is set to 500Pa 2 The concentration of (A) is not less than 97%. After the door of the Mars cabin 1 is closed, the sampling end pneumatic pilot valve 5 and the air return end pneumatic pilot valve 9 are closed, and the CO is closed 2 Gas sourceIn the system, the vacuum pumping system is started until the absolute pressure sensor 17 on the Mars cabin is detected to be 100Pa (the lowest pressure value which can be reached by the Mars cabin in the embodiment), and the valve on the vacuum pumping pipeline 11 is closed. Opening of CO 2 Gas source system for supplying gaseous CO 2 Injecting into the Mars cabin 1 until the absolute pressure sensor 17 is monitored at 100kPa (about normal atmospheric pressure), and turning off the CO 2 Gas supply system and CO is turned on 2 A sampling end pneumatic pilot valve 5 and a return end pneumatic pilot valve 9 of the measuring system are started, the air pump 6 is started again, and the carbon dioxide sensor 8 is used for measuring CO 2 When the values of (2) are stable, the measurement is continued for 5s and the average value (in this case, the concentration of carbon dioxide is about 90% to 92%) is calculated. The above procedure was repeated for a second time with CO measurements at Mars chamber pressure of 100kPa 2 Concentration value of 98%, CO satisfying test 2 The concentration requirement. And finally, starting a vacuum-pumping system, simulating the pressure in the Mars cabin until the absolute pressure is 500Pa, wherein the pressure required for completing the test is 500Pa and CO 2 The concentration of (A) is not less than 97%.
In conclusion, the implementation method and the control system for the carbon dioxide component of the Mars wind tunnel have the advantages of simple principle, simple and flexible structure, low cost and convenient maintenance, are successfully used for the wind tunnel device of the Mars dust cabin, and have strong popularization.
Claims (3)
1. A carbon dioxide component control system for Mars wind tunnel comprises CO 2 Concentration measurement system, CO 2 Air supply system, vacuum pumping system and absolute pressure sensor, its characterized in that: said CO 2 Concentration measurement system, vacuum pumping system and CO 2 The gas source system and the absolute pressure sensor are respectively communicated with the Mars cabin, and the CO is 2 The air source system provides stable CO for the Mars wind tunnel in the Mars cabin 2 A power gas source;
the CO is 2 The concentration measuring system comprises a carbon dioxide measuring flange, a sampling end pneumatic pilot valve, an air pump, a flowmeter, a carbon dioxide sensor and a return end pneumatic pilot valve, wherein the carbon dioxide measuring flange is positioned on the outer wall of the Mars chamber and is fixedly connected with the Mars chamber,the carbon dioxide measuring flange is provided with a sampling air inlet pipe and a sampling air return pipe which are respectively communicated with the inside of the Mars cabin, the sampling air inlet pipe is connected with a sampling end pneumatic pilot valve, the sampling end pneumatic pilot valve is connected with an air suction pump, the air suction pump is connected with a flow meter, the flow meter is connected with a carbon dioxide sensor, the carbon dioxide sensor is connected with an air return end pneumatic pilot valve, and the air return end pneumatic pilot valve is connected with the sampling air return pipe;
CO shutoff 2 Concentration measurement system and CO 2 The air source system is used for starting the vacuumizing system, monitoring an absolute pressure sensor in the Mars cabin and vacuumizing; the vacuum system is closed and CO is turned on 2 Gas source system for supplying gaseous CO 2 Injecting into Mars cabin, monitoring absolute pressure sensor, and closing CO when pressure in the cabin reaches standard atmospheric pressure 2 An air supply system; opening of CO 2 Concentration measurement system: firstly opening a sampling end pneumatic pilot valve and a gas return end pneumatic pilot valve, then starting an air pump, and measuring the stable CO by a carbon dioxide sensor 2 Concentration value of, CO 2 After the concentration measurement is finished, the air pump is firstly closed, then the sampling end pneumatic pilot valve and the air return end pneumatic pilot valve are closed, and CO is finished 2 The concentration of (2); CO meeting the test requirements 2 After the concentration, a vacuumizing system is started, an absolute pressure sensor on the Mars cabin is monitored, and the absolute pressure required by the test is pumped.
2. The system for controlling carbon dioxide composition in a Mars wind tunnel according to claim 1, wherein: the CO2 gas source system comprises a carbon dioxide gas inlet flange, a carbon dioxide gas inlet pipeline and a carbon dioxide gas source device, wherein the carbon dioxide gas inlet flange is positioned on the outer wall of the Mars cabin and is fixedly connected with the Mars cabin, one end of the carbon dioxide gas inlet pipeline is communicated with an ejector of the Mars wind tunnel through the carbon dioxide gas inlet flange, and the other end of the carbon dioxide gas inlet pipeline is communicated with the carbon dioxide gas source device.
3. The system for controlling carbon dioxide composition in a Mars wind tunnel according to claim 1, wherein: the vacuumizing system comprises an air exhaust flange, a vacuum air exhaust pipeline and a vacuumizing device, the air exhaust flange is located on the outer wall of the Mars cabin and fixedly connected with the outer wall of the Mars cabin, one end of the vacuum air exhaust pipeline is communicated with the interior of the Mars cabin through the air exhaust flange, and the other end of the vacuum air exhaust pipeline is communicated with the vacuumizing device.
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002104811A (en) * | 2000-06-30 | 2002-04-10 | Mitsubishi Heavy Ind Ltd | Reduction apparatus of carbon dioxide |
| CN111579261A (en) * | 2020-04-22 | 2020-08-25 | 中国科学院西安光学精密机械研究所 | Mars surface gas composition simulation device and method |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| US7414726B1 (en) * | 2007-10-31 | 2008-08-19 | Bambeck Robert J | Gas analyzer systems and methods |
| CN208921617U (en) * | 2018-07-11 | 2019-05-31 | 中国海洋大学 | It is molten in a kind of water based on TDLAS to deposit CO2Portable detection device |
| US20210146300A1 (en) * | 2019-11-14 | 2021-05-20 | Zayed University | System for carbon sequestration, stabilization of active alkaline solid waste, and a phenomenological approach to calculate carbonation effectiveness |
| CN111579193B (en) * | 2020-04-20 | 2022-05-31 | 哈尔滨工业大学 | Mars dust storm environment simulation device |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002104811A (en) * | 2000-06-30 | 2002-04-10 | Mitsubishi Heavy Ind Ltd | Reduction apparatus of carbon dioxide |
| CN111579261A (en) * | 2020-04-22 | 2020-08-25 | 中国科学院西安光学精密机械研究所 | Mars surface gas composition simulation device and method |
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