Micro-orifice solenoid valve measurement system and method and lunar soil water ice content measurement method

Abstract

This invention discloses a micro-orifice solenoid valve measurement system, method, and lunar soil water ice content measurement method, relating to the field of lunar soil measurement. The micro-orifice solenoid valve measurement system includes a water vapor generating unit that heats ice to form water vapor, and a weighing unit that measures the weight change of the ice. The water vapor generating unit is connected to a pressure stabilizing unit via an inlet pipe with a needle valve. The pressure stabilizing unit is connected to a vacuum tank via an outlet pipe with the micro-orifice solenoid valve to be measured, and a vacuum system is used for evacuation. The measurement method combines the actual pressure value when the pressure of the pressure stabilizing unit changes according to a set gradient with the ice weight change value to determine the relationship between the water vapor mass flow rate of the micro-orifice solenoid valve and the pressure before the valve. In the lunar soil water ice content measurement method, the water vapor generated when the lunar soil is heated passes through the micro-orifice solenoid valve, and the lunar soil water ice content is obtained using the relationship between the water vapor mass flow rate of the micro-orifice solenoid valve and the pressure before the valve. The lunar soil water ice content measurement results of this invention have the advantages of small deviation and high accuracy.

Description

Technical Field

[0001] This invention relates to the field of lunar soil measurement systems and methods, specifically a microporous solenoid valve measurement system, method, and method for measuring lunar soil water ice content. Background Technology

[0002] The origin and composition of water ice in the permanently shadowed regions of the Moon have long been among the most central questions in lunar science. In-situ measurements of water ice mass content are crucial for studying the origin and migration of water on the Moon and in the inner solar system, as well as the formation and evolution of water in atmosphereless celestial bodies. Furthermore, water ice is the Moon's most important resource, determining whether humanity can sustainably develop lunar resources in the future.

[0003] Currently, the internationally recognized upper limit for water ice content in permanently shadowed regions, derived from remote sensing data such as radar and neutron spectra, is between 2% and 30%. In 2009, NASA's LCROSS impact experiment measured the water mass percentage in the Cabeus crater in Antarctica to be 5.6%. However, when high-water-content lunar soil water ice is extracted and introduced into in-situ analyzers, the saturated vapor pressure limits the volatilization of the remaining water ice, leading to increased condensation on the tube walls. This, in turn, results in significant deviations in the quantitative measurement of lunar soil water ice content. Summary of the Invention

[0004] This invention provides a microporous solenoid valve measurement system, method, and lunar soil water ice content measurement method to solve the problem of large deviation in quantitative measurement results due to saturated vapor pressure limit when quantitatively measuring the water ice content of lunar soil with high water content in the prior art.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] The microporous solenoid valve measurement system includes a water vapor generating unit, a weighing unit, a pressure stabilizing unit, a vacuum tank, and a vacuum pumping system; the water vapor generating unit contains ice blocks and heats the ice blocks to generate water vapor, in order to simulate the water vapor mass transfer process during the heating of a lunar soil sample containing water ice;

[0007] The weighing unit is located inside the steam generating unit and is used to measure the weight data of the ice during the heating process.

[0008] The pressure stabilizing unit includes a pressure stabilizing chamber with inlet and outlet ports. The steam generating unit is connected to the inlet port of the pressure stabilizing chamber via an inlet pipe with a needle valve. The outlet port of the pressure stabilizing chamber is connected to a vacuum tank via an outlet pipe. The micro-orifice solenoid valve to be tested is connected to the outlet pipe between the pressure stabilizing chamber and the vacuum tank. Thus, the steam generated by the steam generating unit enters the pressure stabilizing chamber through the needle valve, and then enters the vacuum tank through the open micro-orifice solenoid valve to be tested. The amount of steam entering the pressure stabilizing chamber is adjusted by adjusting the needle valve, thereby adjusting the pressure in the pressure stabilizing chamber within a set pressure variation range. The pressure stabilizing unit is equipped with a pressure sensor, which collects the pressure data in the pressure stabilizing chamber.

[0009] The vacuum system is used to evacuate the interior of the steam generating unit, the interior of the pressure stabilizing chamber, and the interior of the vacuum tank, as well as the inlet pipe between the steam generating unit and the pressure stabilizing chamber, and the outlet pipe between the pressure stabilizing chamber and the vacuum tank.

[0010] Furthermore, the steam generating unit is equipped with a heat-insulating base placed on a weighing device. The height of the heat-insulating base is adjustable. A container for holding ice is placed on the heat-insulating base, and the container is equipped with an induction coil for heating the ice inside the container.

[0011] Furthermore, the steam generating unit is equipped with a pressure sensor and a temperature sensor, which collect pressure and temperature data within the steam generating unit, respectively.

[0012] Furthermore, the voltage stabilizing unit is equipped with a temperature sensor, which collects temperature data within the voltage stabilizing chamber.

[0013] Furthermore, the steam generating unit, the pressure stabilizing unit, the air inlet pipe, and the air outlet pipe are each provided with an insulation layer and a heating belt to maintain the temperature of the steam generating unit, the pressure stabilizing unit, the air inlet pipe, and the air outlet pipe at a set temperature.

[0014] Furthermore, the temperature of the steam generating unit and the voltage stabilizing unit is maintained at 50℃±0.5℃, and the temperature of the air inlet pipe and the air outlet pipe is maintained at 70℃±0.5℃.

[0015] Furthermore, the vacuum system includes a vacuum pump group consisting of a molecular pump and a mechanical pump connected in series. The vacuum pump group is connected to the interior of the water vapor generating unit, the interior of the pressure stabilizing chamber, and the interior of the vacuum tank through vacuum pipelines with shut-off valves.

[0016] A method for measuring a micro-orifice solenoid valve based on the above-mentioned micro-orifice solenoid valve measuring system includes the following steps:

[0017] Step 1: The water vapor generating unit heats the ice to generate water vapor. The water vapor enters the pressure stabilizing chamber through the needle valve, and then enters the vacuum tank through the open microporous solenoid valve to be tested.

[0018] Step 2: Set the pressure variation range in the pressure stabilizing chamber to P. max ± P0~P min ± P0, where P max P min These are the theoretical and lower limits for the range of pressure variation. P0 is the theoretically allowed fluctuation value of the lower limit of the pressure setting range;

[0019] First, adjust the needle valve to control the gas pressure in the pressure stabilizing chamber, and then determine whether the gas pressure in the pressure stabilizing chamber is stable at P by using data collected by the pressure sensor in the pressure stabilizing chamber. max ± When the gas pressure in the pressure-stabilizing chamber stabilizes at P0, max ± At point P0, the actual pressure value P1 in the pressure stabilizing chamber is obtained by the pressure sensor in the pressure stabilizing chamber, and then the gas pressure in the pressure stabilizing chamber is stabilized at point P by the weighing unit. max ± The change in ice weight within time T after P0 is ΔM p1 ;

[0020] Adjust the needle valve again to control the gas pressure in the pressure regulating chamber according to the set pressure gradient. The change in pressure P stabilizes the gas pressure in the pressure-stabilizing chamber at (P). max - P) ± P0, obtain the actual pressure value P2 in the pressure stabilizing chamber at this time, and the gas pressure in the pressure stabilizing chamber stabilizes at (P max - P) ± The change in ice weight within time T after P0 is ΔM p2 ;

[0021] Similarly, the needle valve is adjusted multiple times to control the gas pressure in the pressure-stabilizing chamber according to the set pressure gradient. P stabilizes at P max ± P0 changes until it stabilizes at P. min ± P0, and obtain the actual pressure value P when the pressure in the pressure stabilizing chamber is adjusted to a stable state each time. k And the change in ice weight ΔM within time T after the gas pressure in the pressure stabilizing chamber stabilizes each time. pkk=1,2,3…n;

[0022] Step 3: Based on the data obtained in Step 2, calculate the mass flow rate F of the micro-orifice solenoid valve under different inlet pressures. k =△M pk / T, k=1,2,3…n;

[0023] Then draw P k and F k Scatter plot, where P k This is the actual pressure value when the pressure in the pressure regulating chamber is adjusted to a stable value each time, which is the inlet pressure value of the micro-orifice solenoid valve;

[0024] Finally, the least squares method was used to fit the curve in the scatter plot to obtain the results for different inlet pressure values ​​P. k and the corresponding mass flow rate F k Regression analysis was performed on the data, and the regression formula for the relationship between the water / gas mass flow rate of the micro-orifice solenoid valve and the upstream pressure was obtained as y=a e x / τ +y0, where a, τ, and y0 are the coefficients obtained from the fitting, y is the water-gas mass flow rate, and x is the pressure before the valve of the micro-orifice solenoid valve. The relationship between the water-gas mass flow rate and the pressure before the valve of the micro-orifice solenoid valve is thus determined.

[0025] Furthermore, before the steam generating unit generates steam in step 1, the pressure inside the steam generating unit is maintained below 10 Pa by a vacuum system, and the temperature of the steam generating unit and the pressure stabilizing unit is maintained at 50℃±0.5℃, while the temperature of the inlet pipe and the outlet pipe is maintained at 70℃±0.5℃, before the steam generating unit generates steam.

[0026] The method for measuring water ice content in lunar soil is as follows:

[0027] Step S1: Heat a fixed amount of lunar soil with a weight of m, so that the water vapor generated by the lunar soil flows through the transmission pipeline to the closed microporous solenoid valve.

[0028] Step S2: Measure the pressure inside the transmission pipeline. When the pressure inside the transmission pipeline reaches the upper limit, open the micro-orifice solenoid valve to allow water vapor to pass through the micro-orifice solenoid valve, and record the pressure change curve inside the transmission pipeline during the heating and mass transfer process of lunar soil water ice.

[0029] Based on the pressure change curve recorded during the mass transfer time of lunar soil water ice heating in the transmission pipeline, and combined with the regression formula of the relationship between the water-gas mass flow rate of the micro-orifice solenoid valve and the pressure in front of the valve, which was determined by the method of the micro-orifice solenoid valve, the water-gas mass flow rate change curve is obtained.

[0030] Step S3: Interpolate and integrate the water vapor mass flow rate change curve obtained in step S2 to obtain the total water vapor quantity m. i Based on the weight m of the lunar soil and the total water vapor content m i The water ice content in the lunar soil was calculated.

[0031] In this invention, a micro-orifice solenoid valve is used to measure the water ice content in lunar soil with high water content. This micro-orifice solenoid valve can be used by a corresponding measurement system to simulate different inlet pressure conditions under vacuum, measuring the relationship between the water vapor mass flow rate and the inlet pressure. Therefore, when measuring the water ice content in lunar soil, the water ice content can be obtained based on the pre-determined relationship between the water vapor mass flow rate and the inlet pressure of the micro-orifice solenoid valve, combined with an interpolation integration method. Throughout the entire measurement process, the water vapor formed by the lunar water ice flows through the micro-orifice solenoid valve, thus eliminating the problem of saturated vapor pressure limiting water ice volatilization. Therefore, the final measurement result of the lunar water ice content has small deviation and high accuracy, providing a high-precision measurement method for the quantitative measurement of water ice content in lunar soil with high water ice content in the lunar polar regions. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the micro-orifice solenoid valve measuring system according to Embodiment 1 of the present invention.

[0033] Figure 2 This is a regression analysis curve showing the relationship between the water-gas mass flow rate of the microporous solenoid valve and the pressure before the valve, as measured in Embodiment 1 of the present invention.

[0034] Figure 3 This is a schematic diagram of the soil water ice content measurement system according to Embodiment 2 of the present invention.

[0035] Figure 4 This is a graph showing the changes in water vapor mass flow rate measured three times in Embodiment 2 of the present invention. Detailed Implementation

[0036] To enable those skilled in the art to better understand the present invention, the embodiments will be described in detail below with reference to the accompanying drawings and examples. This will allow for a full understanding of how the present invention uses technical means to solve technical problems and achieve corresponding technical effects, and to facilitate its implementation. The embodiments of the present invention and the various features within them can be combined with each other without conflict, and all resulting technical solutions are within the protection scope of the present invention.

[0037] Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort should fall within the scope of protection of the present invention.

[0038] It should be noted that the terms "comprising" and "having" and any variations thereof in the specification, claims, and accompanying drawings of this invention are intended to cover non-exclusive inclusion.

[0039] Example 1

[0040] like Figure 1 As shown in the figure, this embodiment discloses a microporous solenoid valve measuring system, including a steam generating unit, a weighing unit, a pressure stabilizing unit, a vacuum tank, and a vacuum pumping system.

[0041] The steam generating unit includes a closed chamber with an observation window at the top. The closed chamber is equipped with a first pressure sensor and a first temperature sensor. The first pressure sensor collects the pressure data inside the closed chamber, and the first temperature sensor collects the temperature data inside the closed chamber. The closed chamber is wrapped with an insulation layer and a heating belt. The insulation layer and heating belt maintain the temperature of the closed chamber of the steam generating unit at 50℃±0.5℃.

[0042] The weighing unit employs a high-precision balance, which is integrated into the enclosed chamber of the steam generating unit. The enclosed chamber of the steam generating unit also contains a heat-insulating pad and a container. The heat-insulating pad is placed on the high-precision balance, and the container holds ice cubes and places them on the heat-insulating pad. An induction coil is installed outside the container. This induction coil serves as the device for heating the ice cubes in the steam generating unit. The induction coil heats the ice cubes to generate steam, simulating the water-vapor mass transfer process during the heating of a lunar soil sample containing water ice. The weight change of the ice cubes during the heating process can be measured using the high-precision balance.

[0043] A height-adjustable high-vacuum manipulator is installed on one side of the steam generating unit. The high-vacuum manipulator holds the heat insulation pad, thereby changing the height of the heat insulation pad and thus the height of the container for measurement and periodic calibration of the high-precision balance.

[0044] The pressure stabilizing unit includes a pressure stabilizing chamber with inlet and outlet ports, as well as an inlet pipe, a needle valve, and an outlet pipe. Specifically, the closed chamber of the steam generating unit is connected to the inlet of the pressure stabilizing chamber via the inlet pipe, and the outlet of the pressure stabilizing chamber is connected to the vacuum tank via the outlet pipe. The needle valve is connected to the inlet pipe between the steam generating unit and the pressure stabilizing chamber, and the micro-orifice solenoid valve to be tested is connected to the outlet pipe between the pressure stabilizing chamber and the vacuum tank. Thus, the steam generated by the steam generating unit enters the pressure stabilizing chamber through the needle valve, and then enters the vacuum tank through the open micro-orifice solenoid valve to be tested. The amount of steam entering the pressure stabilizing chamber is adjusted by regulating the needle valve, thereby regulating the pressure within the pressure stabilizing chamber within a set pressure variation range P. max ± P0~P min ± P0 changes, where P max P min These are the theoretical and lower limits for the range of pressure variation. P0 is the theoretically allowed fluctuation value of the lower limit of the pressure setting range.

[0045] The pressure stabilizing chamber is equipped with a second pressure sensor and a second temperature sensor. The second pressure sensor collects the pressure data inside the pressure stabilizing chamber, and the second temperature sensor collects the temperature data inside the pressure stabilizing chamber. Furthermore, the pressure stabilizing chamber is wrapped with an insulation layer and a heating strip, and the inlet and outlet pipes are also wrapped with insulation layers and heating strips, respectively. The insulation layer and heating strip in the pressure stabilizing chamber maintain the temperature at 50℃±0.5℃, and the insulation layer and heating strip in the inlet and outlet pipes maintain the temperature at 70℃±0.5℃.

[0046] The micro-orifice solenoid valve is also wrapped with an insulation layer and a temperature control system. The temperature control system includes a heater and a cooling device, which control the temperature of the micro-orifice solenoid valve at 0°C.

[0047] The vacuum system is used to evacuate the interior of the steam generating unit, the pressure stabilizing chamber, and the vacuum tank, as well as the inlet pipe between the steam generating unit and the pressure stabilizing chamber, and the outlet pipe between the pressure stabilizing chamber and the vacuum tank. Specifically, the vacuum system includes a vacuum pump group consisting of a molecular pump and a mechanical pump connected in series. The pumping speed of the vacuum pump group is greater than or equal to 30 L / s, and the ultimate pressure is less than 10⁻³ Pa.

[0048] The vacuum pump unit has three vacuum ports. One vacuum port is connected to the pressure stabilizing chamber through a vacuum tube with a first shut-off valve. The second vacuum port is connected to the vacuum tank through a vacuum tube with a second shut-off valve. The third vacuum port is connected to the closed chamber of the steam generating unit through a vacuum tube with a third shut-off valve. Thus, the vacuum system can evacuate the inside of the closed chamber of the steam generating unit, the inside of the pressure stabilizing chamber, and the inside of the vacuum tank. At the same time, it can evacuate the inlet pipe between the steam generating unit and the pressure stabilizing chamber, as well as the outlet pipe between the pressure stabilizing chamber and the vacuum tank.

[0049] This embodiment also discloses a method for measuring a micro-orifice solenoid valve based on the above-mentioned micro-orifice solenoid valve measuring system, used to measure the relationship between the water / gas mass flow rate of the micro-orifice solenoid valve and the pressure before the valve, including the following steps:

[0050] Step 1: Preparations before generating water vapor, the process is as follows:

[0051] (1.1) Start the vacuum pump group, open the first shut-off valve, the second shut-off valve and the micro-orifice solenoid valve to be tested, and quickly bypass the pressure stabilizing chamber, vacuum tank and inlet and outlet pipelines to evacuate the air.

[0052] (1.2) Inject liquid water into the container (to prevent low-pressure water from boiling and splashing), then freeze the liquid water in liquid nitrogen. After the liquid water freezes into ice, place the container on the heat insulation pad in the closed chamber of the steam generating unit and allow the ice in the container to heat up naturally. At the same time, open the third shut-off valve to evacuate the closed chamber of the steam sending unit until the pressure displayed by the first pressure sensor is below 10Pa. Then, use a high-vacuum manipulator to lift the heat insulation base into the weighing calibration position, zero the high-precision balance, and record the no-load drift of the high-precision balance within 10 minutes. After recording, put the heat insulation base back into the high-precision balance and record the weighing result data of the balance in real time through the serial port data of the high-precision balance.

[0053] (1.3) The closed chamber of the steam generating unit, the pressure stabilizing chamber of the pressure stabilizing unit, the inlet pipe and the outlet pipe are heated respectively. The temperature of the closed chamber of the steam generating unit and the pressure stabilizing chamber of the pressure stabilizing unit is maintained at 50℃±0.5℃, and the temperature of the inlet pipe and the outlet pipe is maintained at 70℃±0.5℃. This ensures that the steam maintains an adsorption-desorption balance during the flow process and does not condense.

[0054] (1.4) Close the third shut-off valve and use the induction coil to slowly heat the ice in the container until the temperature inside the container rises to the target temperature of 50°C, so that the ice melts into liquid water. After the balance and pressure sensor 1 readings stabilize, the preparation work is completed and the measurement state is entered.

[0055] After completing the preparation work according to the above steps (1.1)-(1.4), the temperature of the micro-orifice solenoid valve is controlled at 0℃, and the liquid water in the container is continuously heated by the induction coil in the inner chamber of the steam generating unit to generate steam. The steam enters the pressure stabilizing chamber through the needle valve, and then enters the vacuum tank through the open micro-orifice solenoid valve to be tested.

[0056] Step 2: Set the pressure variation range in the pressure stabilizing chamber to P. max ± P0~P min ± P0, where P max P min These are the theoretical and lower limits for the range of pressure variation. P0 is the theoretically allowed fluctuation value of the lower limit of the pressure setting range.

[0057] In this embodiment, P max =2000Pa, Pmin =100Pa Let's take P0=10Pa as an example to illustrate.

[0058] First, the needle valve is adjusted to stabilize the gas pressure in the pressure stabilizing chamber. Data collected by the pressure sensor in the pressure stabilizing chamber is used to determine if the gas pressure is stable at 2000 Pa ± 10 Pa. When the gas pressure in the pressure stabilizing chamber is stable at 2000 Pa ± 10 Pa, the actual pressure value P1 in the pressure stabilizing chamber is obtained through the pressure sensor. Then, the weight change ΔM of the ice block within time T (in this embodiment, T = 20 min is used as an example) after the gas pressure in the pressure stabilizing chamber has stabilized at 2000 Pa ± 10 Pa is obtained through the weighing unit. p1 .

[0059] Then, the needle valve is adjusted a second time to control the gas pressure in the pressure-stabilizing chamber according to the set pressure change gradient. The pressure P is varied from 100 Pa to stabilize the gas pressure in the pressure-stabilizing chamber at (2000 Pa - 100 Pa = 1900 Pa) ± 10 Pa. The actual pressure value P2 in the pressure-stabilizing chamber at this point is obtained, as well as the change in the weight of the ice block ΔM within 20 minutes after the gas pressure in the pressure-stabilizing chamber stabilizes at 1900 Pa ± 10 Pa. p2 .

[0060] The needle valve is adjusted a third time to control the gas pressure in the pressure-stabilizing chamber to change according to the set pressure gradient. The pressure P is varied from 100 Pa to stabilize the gas pressure in the pressure stabilizing chamber at 1800 Pa ± 10 Pa. The actual pressure value P3 in the pressure stabilizing chamber at this point is obtained, as well as the change in the weight of the ice block ΔM over a time T = 20 minutes after the gas pressure in the pressure stabilizing chamber stabilizes at 1800 Pa ± 10 Pa. p3 .

[0061] Similarly, the needle valve is adjusted multiple times to control the gas pressure in the pressure-stabilizing chamber according to the set pressure gradient. Pressure P was initially stable at 2000 Pa ± 10 Pa, then stabilized at 100 Pa ± 10 Pa. To verify the stability of the gas at low pressure and the validity of the data, the needle valve was adjusted until the gas pressure in the stabilizing chamber was stabilized at 100 Pa ± 10 Pa. The actual pressure value P in the stabilizing chamber at this point was then obtained. n And the change in ice weight ΔM within 20 minutes after the gas pressure in the pressure stabilizing chamber stabilizes at 100Pa±10Pa. pn .

[0062] Thus, the actual pressure value P when the pressure in the pressure stabilizing chamber is adjusted to a stable value each time is obtained. kAnd the change in ice weight ΔM within 20 minutes after the gas pressure in the pressure stabilizing chamber stabilizes each time. pk , k=1,2,3…n.

[0063] Step 3: Based on the data obtained in Step 2, calculate the mass flow rate F of the micro-orifice solenoid valve under different inlet pressures. k =△M pk / T, k=1,2,3…n. Then plot P. k and F k Scatter plot, where P k This is the actual pressure value when the pressure in the pressure regulating chamber is adjusted to a stable value each time, which is the inlet pressure value of the micro-orifice solenoid valve.

[0064] Finally, the least squares method was used to fit the curve in the scatter plot to obtain the results for different inlet pressure values ​​P. k and the corresponding mass flow rate F k Regression analysis was performed on the data, and the regression formula for the relationship between the water / gas mass flow rate of the micro-orifice solenoid valve and the upstream pressure was obtained as y=a e x / τ +y0, where a, τ, and y0 are the fitted coefficients, y is the water-gas mass flow rate, and x is the pressure before the micro-orifice solenoid valve. This allows us to determine the relationship between the water-gas mass flow rate and the pressure before the valve of the micro-orifice solenoid valve. In this embodiment, as shown... Figure 2 As shown, the coefficients obtained through fitting are a = 3.7022, τ = 1699.8396, y0 = 0.4995, and the correlation R² is 0.9443, thus the regression formula is y = 3.7022. e x / 1699.8396 +0.4995.

[0065] Example 2

[0066] This embodiment discloses a lunar soil water ice content measurement system, such as... Figure 3 As shown, the device includes a sample inlet funnel, a volumetric sample receiving cup, a heating furnace cylinder, a transmission pipeline, a vacuum gauge, a vacuum system, and a micro-orifice solenoid valve for determining the regression formula of the relationship between water vapor mass flow rate and valve inlet pressure according to the micro-orifice solenoid valve measurement system and method described in Example 1.

[0067] A fixed quantity of lunar soil is loaded into a constant-volume sample collection cup via a sample funnel. The collection cup is then placed inside a heating furnace, which is connected to a vacuum system via a transmission pipeline. A micro-orifice solenoid valve is connected to the transmission pipeline. When the heating furnace heats the lunar soil in the collection cup, it generates water vapor. This water vapor travels through the transmission pipeline to the micro-orifice solenoid valve. A vacuum gauge is used to measure the gas pressure inside the transmission pipeline. This results in a lunar soil water ice content measurement system. During operation, the temperature of the micro-orifice solenoid valve is maintained at 0°C.

[0068] This embodiment also discloses a method for measuring the water ice content of lunar soil, the process of which is as follows:

[0069] Step S1: The lunar soil with a quantitative weight of m in the constant volume sample cup is heated by the heating furnace cylinder, so that the water vapor generated by the lunar soil flows to the closed microporous solenoid valve through the transmission pipeline.

[0070] Step S2: Measure the pressure inside the transmission pipeline using a vacuum gauge. When the pressure inside the transmission pipeline reaches the upper limit, open the micro-orifice solenoid valve and activate the vacuum system to allow water vapor to be drawn away by the vacuum system through the micro-orifice solenoid valve. At this time, record the pressure change curve inside the transmission pipeline during the mass transfer process of lunar soil water ice heating.

[0071] The pressure change curve recorded during the mass transfer process of lunar soil water ice heating within the transmission pipeline is used as the regression formula y=3.7022 for the relationship between the water-gas mass flow rate of the micro-orifice solenoid valve and the pressure before the valve, as determined by the micro-orifice solenoid valve measurement system and method described in Embodiment 1. e x / 1699.8396 The parameter x in +0.4995 is used to derive the regression formula y=3.7022 for the relationship between the water / gas mass flow rate of the micro-orifice solenoid valve and the pressure before the valve. e x / 1699.8396 The curve for parameter y in +0.4995 is the curve showing the change in water-gas mass flow rate.

[0072] Step S3: Interpolate and integrate the water vapor mass flow rate change curve obtained in step S2 to obtain the total water vapor quantity m. i Based on the weight m of the lunar soil and the total water vapor content m i The calculated lunar soil water ice content Xi=m i / m.

[0073] In this embodiment, multiple quantitative measurements of the same weight can be performed according to steps S1-S3, thereby obtaining multiple measured values ​​of water ice content in lunar soil of the same quantitative weight. This embodiment uses three quantitative measurements as an example for illustration. The weight of the lunar soil in each of the three quantitative measurements is m=1.4g. The water vapor mass flow rate change curves obtained from the three quantitative measurements are shown below. Figure 4 As shown. For Figure 4 Interpolate and integrate the three water vapor mass flow rate curves to obtain the total water vapor masses m1, m2, and m3 for three lunar soil weights of 1.4 g. Then, the lunar soil water ice content Xi = m i / m, i=1, 2, 3. After obtaining three measurements of water ice content X1, X2, X3 for lunar soil samples with a weight of 1.4g each, the average value was taken and finally used as the water ice content value of lunar soil samples with a weight of 1.4g each.

[0074] The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings. These embodiments are merely descriptions of preferred embodiments and are not intended to limit the scope or concept of the invention. The specific technical features described in the above embodiments can be combined in any suitable manner without contradiction. Such combinations, as long as they do not violate the spirit of the present invention, should also be considered as part of this disclosure. To avoid unnecessary repetition, the present invention will not further describe the various possible combinations.

[0075] This invention is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this invention and without departing from the design idea of ​​this invention, all modifications and improvements made by those skilled in the art to the technical solutions of this invention should fall within the protection scope of this invention. The technical content for which protection is sought in this invention has been fully described in the claims.

Claims

1. A micro-orifice solenoid valve measuring system, characterized in that, It includes a water vapor generating unit, a weighing unit, a pressure stabilizing unit, a vacuum tank, and a vacuum pumping system; the water vapor generating unit contains ice blocks and heats the ice blocks to generate water vapor, in order to simulate the water vapor mass transfer process during the heating of lunar soil samples containing water ice; The weighing unit is located inside the steam generating unit and is used to measure the weight data of the ice during the heating process. The pressure stabilizing unit includes a pressure stabilizing chamber with inlet and outlet ports. The steam generating unit is connected to the inlet port of the pressure stabilizing chamber via an inlet pipe with a needle valve. The outlet port of the pressure stabilizing chamber is connected to a vacuum tank via an outlet pipe. The micro-orifice solenoid valve to be tested is connected to the outlet pipe between the pressure stabilizing chamber and the vacuum tank. Thus, the steam generated by the steam generating unit enters the pressure stabilizing chamber through the needle valve, and then enters the vacuum tank through the open micro-orifice solenoid valve to be tested. The amount of steam entering the pressure stabilizing chamber is adjusted by adjusting the needle valve, thereby adjusting the pressure in the pressure stabilizing chamber within a set pressure variation range. The pressure stabilizing unit is equipped with a pressure sensor, which collects the pressure data in the pressure stabilizing chamber. The vacuum system is used to evacuate the interior of the steam generating unit, the interior of the pressure stabilizing chamber, and the interior of the vacuum tank, as well as the inlet pipe between the steam sending unit and the pressure stabilizing chamber, and the outlet pipe between the pressure stabilizing chamber and the vacuum tank. The water vapor generating unit heats the ice to produce water vapor, which enters the pressure stabilizing chamber through the needle valve, and then enters the vacuum tank through the open micro-orifice solenoid valve to be tested, so that the water vapor is drawn away by the vacuum system through the micro-orifice solenoid valve. The needle valve is adjusted multiple times to control the gas pressure in the pressure regulating chamber according to the set pressure gradient. P stabilizes at P max ± P0 changes until it stabilizes at P. min ± P0, and obtain the actual pressure value P when the pressure in the pressure stabilizing chamber is adjusted to a stable state each time. k And the change in ice weight ΔM within time T after the gas pressure in the pressure stabilizing chamber stabilizes each time. pk , k=1,2,3…n; Calculate the mass flow rate F of the micro-orifice solenoid valve under different inlet pressures. k =△M pk / T, k=1,2,3…n; then plot P k and F k Scatter plot, where P k The pressure value is the actual pressure value at which the pressure in the pressure-stabilizing chamber is adjusted to a stable value each time, i.e., the inlet pressure value of the micro-orifice solenoid valve; finally, the curve in the scatter plot is fitted using the least squares method to obtain the pressure values ​​P before the valve. k and the corresponding mass flow rate F k Regression analysis was performed on the data, and the regression formula for the relationship between the water / gas mass flow rate of the micro-orifice solenoid valve and the upstream pressure was obtained as y=a e x / τ +y0, where a, τ, and y0 are the coefficients obtained from the fitting, y is the water-gas mass flow rate, and x is the pressure before the valve of the micro-orifice solenoid valve. The relationship between the water-gas mass flow rate and the pressure before the valve of the micro-orifice solenoid valve is thus determined.

2. The micro-orifice solenoid valve measuring system according to claim 1, characterized in that, The steam generating unit is equipped with an insulated base placed on a weighing device. The height of the insulated base is adjustable. A container for holding ice is placed on the insulated base. The container is equipped with an induction coil for heating the ice inside the container.

3. The micro-orifice solenoid valve measuring system according to claim 1, characterized in that, The steam generating unit is equipped with a pressure sensor and a temperature sensor, which collect pressure and temperature data within the steam generating unit, respectively.

4. The micro-orifice solenoid valve measuring system according to claim 1, characterized in that, The voltage regulator unit is equipped with a temperature sensor, which collects temperature data inside the voltage regulator chamber.

5. The micro-orifice solenoid valve measuring system according to claim 1, characterized in that, The steam generating unit, the pressure stabilizing unit, the inlet pipe, and the outlet pipe are each provided with an insulation layer and a heating belt to maintain the temperature of the steam generating unit, the pressure stabilizing unit, the inlet pipe, and the outlet pipe at the set temperature.

6. The micro-orifice solenoid valve measuring system according to claim 5, characterized in that, The temperature of the steam generating unit and the voltage stabilizing unit is maintained at 50℃±0.5℃, and the temperature of the air inlet pipe and the air outlet pipe is maintained at 70℃±0.5℃.

7. The micro-orifice solenoid valve measuring system according to claim 1, characterized in that, The vacuum system includes a vacuum pump group consisting of a molecular pump and a mechanical pump connected in series. The vacuum pump group is connected to the interior of the water vapor generating unit, the interior of the pressure stabilizing chamber, and the interior of the vacuum tank through vacuum pipelines with shut-off valves.

8. A method for measuring a micro-orifice solenoid valve based on the micro-orifice solenoid valve measuring system according to any one of claims 1-7, characterized in that, Includes the following steps: Step 1: The water vapor generating unit heats the ice to generate water vapor. The water vapor enters the pressure stabilizing chamber through the needle valve, and then enters the vacuum tank through the open microporous solenoid valve to be tested. Step 2: Set the pressure variation range in the pressure stabilizing chamber to P. max ± P0~P min ± P0, where P max P min These are the theoretical and lower limits for the range of pressure variation. P0 is the theoretically allowed fluctuation value of the lower limit of the pressure setting range; First, adjust the needle valve to control the gas pressure in the pressure stabilizing chamber, and then determine whether the gas pressure in the pressure stabilizing chamber is stable at P by using data collected by the pressure sensor in the pressure stabilizing chamber. max ± When the gas pressure in the pressure-stabilizing chamber stabilizes at P0, max ± At point P0, the actual pressure value P1 in the pressure stabilizing chamber is obtained by the pressure sensor in the pressure stabilizing chamber, and then the gas pressure in the pressure stabilizing chamber is stabilized at point P by the weighing unit. max ± The change in ice weight within time T after P0 is ΔM p1 ; Adjust the needle valve again to control the gas pressure in the pressure regulating chamber according to the set pressure gradient. The change in pressure P stabilizes the gas pressure in the pressure-stabilizing chamber at (P). max - P) ± P0, obtain the actual pressure value P2 in the pressure stabilizing chamber at this time, and the gas pressure in the pressure stabilizing chamber stabilizes at (P max - P) ± The change in ice weight within time T after P0 is ΔM p2 ; Similarly, the needle valve is adjusted multiple times to control the gas pressure in the pressure-stabilizing chamber according to the set pressure gradient. P stabilizes at P max ± P0 changes until it stabilizes at P. min ± P0, and obtain the actual pressure value P when the pressure in the pressure stabilizing chamber is adjusted to a stable state each time. k And the change in ice weight ΔM within time T after the gas pressure in the pressure stabilizing chamber stabilizes each time. pk k=1,2,3…n; Step 3, based on the data obtained in step 2, calculate the mass flow F of the micro-hole electromagnetic valve under different pre-valve pressures k =△M pk / T, k = 1, 2, 3…n; Then draw P k and F k Scatter plot, where P k This is the actual pressure value when the pressure in the pressure regulating chamber is adjusted to a stable value each time, which is the inlet pressure value of the micro-orifice solenoid valve; Finally, the least squares method was used to fit the curve in the scatter plot to obtain the results for different inlet pressure values ​​P. k and the corresponding mass flow rate F k Regression analysis was performed on the data, and the regression formula for the relationship between the water / gas mass flow rate of the micro-orifice solenoid valve and the upstream pressure was obtained as y=a e x / τ +y0, where a, τ, and y0 are the coefficients obtained from the fitting, y is the water-gas mass flow rate, and x is the pressure before the valve of the micro-orifice solenoid valve. The relationship between the water-gas mass flow rate and the pressure before the valve of the micro-orifice solenoid valve is thus determined.

9. The method for measuring a micro-orifice solenoid valve according to claim 8, characterized in that, Before the steam generating unit produces steam in step 1, the pressure inside the steam generating unit is maintained below 10Pa by a vacuum system, and the temperature of the steam generating unit and the pressure stabilizing unit is maintained at 50℃±0.5℃, while the temperature of the inlet pipe and the outlet pipe is maintained at 70℃±0.5℃. Then the steam generating unit is made to produce steam.

10. A method for measuring water ice content in lunar soil, characterized in that, The process is as follows: Step S1: Heat a fixed amount of lunar soil with a weight of m, so that the water vapor generated by the lunar soil flows through the transmission pipeline to the closed microporous solenoid valve. Step S2: Measure the pressure inside the transmission pipeline. When the pressure inside the transmission pipeline reaches the upper limit, open the micro-orifice solenoid valve to allow water vapor to pass through the micro-orifice solenoid valve, and record the pressure change curve inside the transmission pipeline during the heating and mass transfer process of lunar soil water ice. Based on the pressure change curve recorded in the transmission pipeline during the heating and mass transfer process of lunar soil water ice, and combined with the regression formula of the relationship between the water-gas mass flow rate of the micro-orifice solenoid valve and the pressure before the valve as determined by the micro-orifice solenoid valve measurement method as described in claim 8 or 9, the water-gas mass flow rate change curve is obtained. Step S3: Interpolate and integrate the water vapor mass flow rate change curve obtained in step S2 to obtain the total water vapor quantity m. i Based on the weight m of the lunar soil and the total water vapor content m i The water ice content in the lunar soil was calculated.

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