Ultralow-pressure dynamic stable control high-temperature hydrogen permeation testing device

Abstract

The invention discloses an ultra-low-pressure dynamic stable control high-temperature hydrogen permeation testing device, which belongs to the technical field of permeation testing and comprises a gas supply unit, a pressure and mass flow control unit, a first vacuum pumping unit, a permeation testing unit, a heating unit and a closed-loop control unit. And the air exhaust rate and the air inlet flow are adjusted in real time, so that pressure fluctuation in the vacuum reaction cavity is inhibited, dynamic stability under extremely low pressure is realized, and accurate and repeatable pressure conditions are provided for experiments.

Description

Technical Field

[0001] The present invention relates to the technical field of penetration testing, and particularly to a high-temperature hydrogen penetration testing device with ultra-low pressure dynamic stability control. Background Art

[0002] Nuclear fusion is a process of combining light atomic nuclei (such as isotopes of hydrogen) into heavier atomic nuclei, during which a huge amount of energy is released. To achieve nuclear fusion, it is necessary to heat the fuel (usually deuterium and tritium) to a high temperature of millions of degrees Celsius to make it reach the plasma state and maintain it under sufficient pressure for a long enough time to make the fusion reaction continue. The hydrogen penetration performance of materials in a high-temperature and extremely low-pressure environment directly affects the efficiency and safety of fusion devices.

[0003] Penetration testing devices can be used to test the penetration performance of different materials and ensure the efficiency and safety of fusion devices. Through material testing, simulation experiments, and data analysis, they provide technical support for the practical application of fusion energy. However, in an extremely low-pressure test environment, the existing penetration testing devices have the following defects:

[0004] 1. Poor material compatibility: Many materials may deform, corrode, or degrade structurally at high temperatures, which affects the long-term stability and reliability of the device. Materials with high temperature resistance and good mechanical properties need to be found.

[0005] 2. Unstable pressure control: Under high-temperature and extremely low-pressure conditions, the pressure fluctuates greatly, resulting in reduced repeatability and reliability of test results.

[0006] 3. Slow response speed: It is difficult to measure the gas permeability at high temperatures. The existing pressure control systems have a slow response speed when adjusting extremely low pressures and are not suitable for the test requirements of dynamic pressure changes.

[0007] 4. Weak anti-interference ability: Data acquisition in a high-temperature environment may be interfered with, and high signal-to-noise ratio sensors and signal processing technologies are required. The test devices in an extremely low-pressure environment are easily affected by external environmental factors such as temperature changes and vibrations, which will affect the accuracy of the test.

[0008] 5. Complex structure: The existing pressure control devices often have a complex structure, are difficult to operate and maintain, and are not conducive to long-term operation under extremely low-pressure conditions.

[0009] The existing technologies have not effectively solved the above problems, and there is an urgent need for a penetration testing device with extremely low-pressure dynamic control with high precision, high stability, and anti-interference ability. Summary of the Invention

[0010] The object of the present invention is to overcome the technical problems existing in the prior art, and provide an ultra-low pressure dynamic stability control high-temperature hydrogen permeation test device, which can provide high-precision and high-stability pressure control at extremely low pressures, and at the same time has fast response ability and good anti-interference performance to meet the needs of the scientific research and industrial fields for extremely low pressure test environments.

[0011] The object of the present invention is achieved by the following technical solutions:

[0012] An ultra-low pressure dynamic stability control high-temperature hydrogen permeation test device, comprising:

[0013] A gas supply unit for supplying a mixture of hydrogen isotope gas and argon gas to the vacuum reaction chamber;

[0014] A pressure and mass flow control unit connected between the vacuum reaction chamber and the gas supply unit for controlling the flow rate of the gas supply and the pressure in the vacuum reaction chamber;

[0015] A first vacuum pumping unit for pumping out the gas in the vacuum reaction chamber and maintaining the vacuum degree of the vacuum reaction chamber;

[0016] A permeation test unit connected to the vacuum reaction chamber for permeation test and gas composition analysis;

[0017] A heating unit for heating the vacuum reaction chamber;

[0018] A closed-loop control unit for monitoring the pressure and temperature in the vacuum reaction chamber, and controlling the actions of the gas supply unit and the vacuum pumping unit in real time according to the monitored pressure value, and controlling the action of the heating unit in real time according to the monitored temperature value.

[0019] In some embodiments, the pressure and mass flow control unit specifically includes a pressure controller and a mass flow controller.

[0020] In some embodiments, the first vacuum pumping unit is connected to the vacuum reaction chamber, and specifically includes a pumping pump group composed of a molecular pump, an ion pump, and a mechanical pump.

[0021] In some embodiments, the permeation test unit includes a permeation window probe, a vacuum detection chamber, and a quadrupole mass spectrometer connected in sequence.

[0022] In some embodiments, a second vacuum pumping unit is connected to the vacuum detection chamber, and the second vacuum pumping unit specifically includes a pumping pump group composed of a molecular pump, an ion pump, and a mechanical pump.

[0023] In some embodiments, the heating unit includes a high-temperature furnace.

[0024] In some embodiments, the closed-loop control unit includes a sensor group and a main control chip, and the sensor group includes a thin-film gauge and a temperature detection sensor.

[0025] It should be further noted that the above-mentioned technical features corresponding to each option can be combined or replaced with each other without conflict to form a new technical solution.

[0026] The device precisely adjusts the gas flow rate at the gas inlet end of the vacuum reaction chamber through the pressure and mass flow control unit, and at the same time uses the closed-loop control unit to monitor the pressure inside the vacuum reaction chamber to ensure that the pressure is stably maintained at an extremely low level. The molecular pump group configured by the first vacuum pumping unit realizes a low background pressure, quickly pumps out the gas inside the chamber, maintains the vacuum degree of the test environment, and reaches a dynamic equilibrium. The entire system adjusts the pumping rate and the intake gas flow in real time through closed-loop feedback control to suppress pressure fluctuations, achieve dynamic stability under extremely low pressure, and provide accurate and repeatable pressure conditions for the experiment. Compared with the prior art, the beneficial effects of the present invention are as follows:

[0027] 1. Ultra-low pressure control: It can achieve precise control under extremely low pressure (1 - 50 Pa, accuracy ±0.5 Pa), and is applicable to scientific research and industrial applications that require an ultra-low pressure environment.

[0028] 2. Precise pressure control: Advanced pressure and mass flow controllers are adopted to achieve precise regulation of the low-pressure environment. Different types of pumps are used in combination to ensure quickly reaching and maintaining the required vacuum degree.

[0029] 3. Ultra-low pressure dynamic stability control: The test device integrates a variety of advanced technologies and equipment, forming a complete set of low-pressure environment test solutions. It is not only applicable to the field of scientific research, but also can be applied to quality control and safety assurance in industrial production, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the composition of a high-temperature hydrogen permeation test device for ultra-low pressure dynamic stability control shown in the embodiments of the present invention;

[0031] Figure 2 It is a schematic diagram of the specific structure of the permeation test device shown in the embodiments of the present invention;

[0032] Figure 3 It is a detection schematic diagram of the permeation window probe shown in the embodiments of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0033] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Components of the embodiments of the present application described and illustrated herein can generally be arranged and designed in various different configurations. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0034] It should be noted that all the defects existing in the above prior art solutions are the results obtained by the inventor through practice and careful research. Therefore, the process of discovering the above problems and the solutions proposed by the embodiments of the present application below for the above problems should be the contributions made by the inventor to the present application during the invention creation process, and should not be understood as the technical content known to those skilled in the art.

[0035] Referring to Figure 1 , a super-low pressure dynamic stability control high-temperature hydrogen permeation test device, comprising:

[0036] A gas supply unit for supplying a mixture of hydrogen isotope gas and argon gas to the vacuum reaction chamber;

[0037] A pressure and mass flow control unit connected between the vacuum reaction chamber and the gas supply unit for controlling the flow rate of gas supply and the pressure in the vacuum reaction chamber;

[0038] A first vacuum pumping unit for pumping out the gas in the vacuum reaction chamber and maintaining the vacuum degree of the vacuum reaction chamber;

[0039] A permeation test unit connected to the vacuum reaction chamber for permeation test and gas component analysis;

[0040] A heating unit for heating the vacuum reaction chamber;

[0041] A closed-loop control unit for monitoring the pressure and temperature in the vacuum reaction chamber, and controlling the actions of the gas supply unit and the vacuum pumping unit in real time according to the monitored pressure value, and controlling the action of the heating unit in real time according to the monitored temperature value.

[0042] The device precisely adjusts the gas flow rate at the gas inlet end of the vacuum reaction chamber through the pressure and mass flow control unit, and at the same time uses the closed-loop control unit to monitor the pressure in the vacuum reaction chamber to ensure that the pressure is stable at an extremely low level. The molecular pump group configured in the first vacuum pumping unit realizes a low background pressure, quickly pumps out the gas in the chamber, maintains the vacuum degree of the test environment, and reaches a dynamic balance. The entire system adjusts the pumping rate and the intake gas flow rate in real time through closed-loop feedback control to suppress pressure fluctuations, realizes dynamic stability at extremely low pressures, and provides accurate and repeatable pressure conditions for the experiment.

[0043] Reference Figure 2 , the gas supply unit includes a gas supply source (such as a gas storage tank filled with D2 / Ar or H2 / Ar in the tank), and the pressure and mass flow control unit specifically includes a pressure controller and a mass flow controller, which provide the gas required for the experiment and control the gas flow rate.

[0044] The first vacuum pumping unit is connected to the vacuum reaction chamber and specifically includes a pumping unit composed of a molecular pump, an ion pump, and a mechanical pump, which is used to maintain a high vacuum state in the vacuum reaction chamber and remove air and other impurities. Among them, the mechanical pump is a two-stage oil-sealed mechanical pump, and the ion pump further provides an oil-free and ultra-clean pumping environment to reduce pollution. The penetration test unit includes a penetration window probe (specific connection as Figure 3 ), a vacuum detection chamber, and a quadrupole mass spectrometer (QMS), which are used for penetration testing and gas composition analysis.

[0045] A second vacuum pumping unit is connected to the vacuum detection chamber. The second vacuum pumping unit specifically includes a pumping unit composed of a molecular pump, an ion pump, and a mechanical pump. The specific pump unit can be combined according to actual conditions, such as Figure 2 selecting a molecular pump and an ion pump in

[0046] to maintain a high vacuum state in the vacuum detection chamber.

[0047] The heating unit includes a high-temperature furnace, which is used to heat the vacuum reaction chamber to a set temperature.

[0048] Furthermore, the gas supply source (D2 / Ar or H2 / Ar) provides a mixture of hydrogen isotope gas and argon required for the experiment. The first vacuum pumping unit is configured with a molecular pump group to achieve a low background pressure, and at the same time, a mechanical pump is connected in parallel and cooperates with the mass flow controller at the inlet end to precisely control the pressure in the vacuum reaction chamber. By adding a ball valve at the front end of the mechanical pump, stable control of 100 - 1000 Pa D2 / Ar in the chamber is achieved, ensuring the accuracy of the experimental conditions. The thin film gauge is used to measure the pressure in the vacuum chamber and feedback it to the main control chip of the control system to adjust the pumping rate. The penetration window probe is in the sealed vacuum reaction chamber, and α-Fe is used to ensure low hydrogen permeability and durability, with a leak rate < 1x10 -19At a rate of pa·m / s, gaseous hydrogen diffuses from the vacuum reaction chamber into the permeation window, and the permeated gas reaches the vacuum detection chamber. Then, the QMS (quadrupole mass spectrometer) analyzes the gas composition and permeation rate in the vacuum detection chamber in real time to detect by-products or residual gases during the reaction. The high-temperature furnace heats a specific area, and the required experimental heating temperature is set. The molecular pump and ion pump maintain the high-vacuum state of the system, removing air and other impurities. The valve and pipeline system connect each component to control the flow path and direction of the gas.

[0049] The overall working process of the device is as follows:

[0050] Open the gas supply source and set the required pressure and mass flow parameters. Use the pressure and mass flow controllers to stabilize the gas pressure in the system at the preset value. Start the high-temperature furnace and keep it constant after reaching the set temperature. Continuously monitor the pressure change through the diaphragm gauge, adjust the intake flow rate of the mass flow controller, and at the same time, according to the reading of the diaphragm gauge, the feedback control system adjusts the pumping speed in a cycle. After the temperature and pressure are stable, start to calibrate the signal peak position of the mass spectrum and analyze the gas composition and permeation data through the QMS. Collect data from each sensor for real-time analysis and recording. Record data such as pressure, flow rate, and gas composition through computer software. Process and analyze the data to evaluate the experimental results and the performance of the system.

[0051] Furthermore, combined with Figure 2 and the working process of the above device, the specific details of the test are given, including:

[0052] 1. First, turn on the pump group switch of the first vacuum pumping unit.

[0053] 2. Open the gas supply unit and introduce a mixture of deuterium and argon into the vacuum reaction chamber.

[0054] 3. Turn on all pump group switches, and check that the three valves (the valves above and below the vacuum reaction chamber and at the flow meter) of the pressure controller pipeline are in the open state.

[0055] 4. Ensure that the mechanical pump valve is open (the molecular pump pressure should not exceed 10-3 hPa).

[0056] 5. Turn off the molecular pump group to slow down the pumping speed and prevent damage to the molecular pump.

[0057] 6. Adjust the flow meter to 9 sccm and adjust the size of the mechanical pump valve to make the ventilation pressure stable at about 1 kPa. The controller adjusts the system pressure and flow rate to reach the preset value.

[0058] 7. After the ventilation pressure is stable at about 1 kPa, adjust the flow meter to adjust the ventilation pressure to be close to 1 kPa.

[0059] 8. Turn off the flowmeter switch and heat the high-temperature furnace to the set temperature.

[0060] 9. After starting the high-temperature furnace and heating it to the set temperature, turn on the flowmeter switch and adjust it to about 1 kPa. Monitor the system pressure using a diaphragm gauge and adjust the pumping rate in real time according to the pressure change to maintain the system pressure stable.

[0061] 10. Start calibrating the signal peak position of the mass spectrometer.

[0062] 11. Use a quadrupole mass spectrometer to analyze the gas composition and permeation rate in real time.

[0063] 12. Use the computer control software to record data such as pressure, flow rate, temperature, and gas composition.

[0064] 13. Process and analyze the data, calculate parameters such as the permeability, and evaluate the permeation performance and stability of the material.

[0065] 14. First, close the inlet end, and check that the three valves of the gas flowmeter and the pressure controller pipeline are in the closed state.

[0066] 15. Turn off the high-temperature furnace to cool down.

[0067] 16. Turn on the mechanical pump and the molecular pump set to pump air. At the same time, note that the molecular pump pumps to a vacuum (the pressure of the molecular pump should not exceed 10-3 hPa), and when the pressure drops to about 0 Pa, turn off the mechanical pump set.

[0068] 17. Turn off the switches at the upper and lower ends of the vacuum reaction chamber.

[0069] 18. Turn off the mass spectrometer filament.

[0070] Data analysis mainly involves the following aspects:

[0071] Permeability is a parameter that measures the ability of a material (such as liquid lead-lithium, etc.) to allow gases or liquids to pass through under specific conditions, and represents the permeation amount per unit area per unit time. The formula for steady-state permeability is as follows:

[0072] K = (Q / A) / t (1)

[0073] In the formula, K is the permeability (m 2 ), Q is the permeation amount (mol); A is the permeation area (m 2 ); t is the permeation time (s); The transient permeability refers to the number of moles of gas or liquid passing through per unit area per unit time when the system has not reached a stable state. Its formula is:

[0074] P = dQ / (A*dP*dt) (2)

[0075] Wherein, dQ is the change in the amount of permeation (mol); dP is the change in the pressure difference (Pa); dt is the change in time (s); Fick's first law of diffusion describes the diffusion process of substances in a homogeneous medium. Its formula is:

[0076] J = -D * (dC / dx) (3)

[0077] Wherein, J is the diffusion flux (mol / m / s); D is the diffusion coefficient (m / s); C is the concentration of hydrogen in solid solution; the diffusion coefficient represents the amount of substance passing through a unit area per unit time, and the diffusion coefficient is obtained by the time lag method.

[0078] D = L 2 / 6t L (4)

[0079] Wherein, the point marked as tb starting from the 0th moment represents the breakthrough time, and the time required for the permeation to reach 0.63 times the steady-state value is tL, and L is the thickness of the sample.

[0080] The above specific embodiments are detailed descriptions of the present invention. It cannot be determined that the specific embodiments of the present invention are only limited to these descriptions. For those of ordinary skill in the technical field to which the present invention pertains, without departing from the concept of the present invention, several simple deductions and substitutions can still be made, and all should be regarded as belonging to the protection scope of the present invention.

Claims

1. An ultra-low pressure dynamic stable control high temperature hydrogen permeation test device, characterized in that: include: A gas supply unit, used for providing a mixture of hydrogen isotope gas and argon gas into the vacuum reaction chamber; A pressure and mass flow control unit, connected between the vacuum reaction chamber and the gas supply unit, for controlling the flow of the gas supply and the pressure in the vacuum reaction chamber; A first vacuum pumping unit, used to pump out the gas in the vacuum reaction chamber and maintain the vacuum degree of the vacuum reaction chamber; A penetration test unit connected to the vacuum reaction chamber and used for penetration testing and gas composition analysis; A heating unit, used for heating the vacuum reaction chamber; The closed-loop control unit is used to monitor the pressure and temperature in the vacuum reaction chamber, and to control the actions of the gas supply unit and the vacuum pumping unit in real time according to the monitored pressure value, and to control the actions of the heating unit in real time according to the monitored temperature value.

2. The ultra-low pressure dynamic stability control high temperature hydrogen permeation test device according to claim 1, characterized in that: The pressure and mass flow control unit specifically includes a pressure controller and a mass flow controller.

3. The ultra-low pressure dynamic stability control high temperature hydrogen permeation test device according to claim 1, characterized in that: The first vacuum pumping unit is connected to the vacuum reaction chamber, and specifically comprises a pumping pump group consisting of a molecular pump, an ion pump, and a mechanical pump.

4. The ultra-low pressure dynamic stability control high temperature hydrogen permeation test device according to claim 1, characterized in that: The penetration test unit comprises a penetration window probe, a vacuum detection chamber, and a quadrupole mass spectrometer which are connected in sequence.

5. The ultra-low pressure dynamic stability control high temperature hydrogen permeation test device according to claim 4, characterized in that: The vacuum detection chamber is connected to a second vacuum pumping unit, which specifically includes a pumping pump group consisting of a molecular pump, an ion pump, and a mechanical pump.

6. The ultra-low pressure dynamic stability control high temperature hydrogen permeation test device according to claim 1, characterized in that: The heating unit includes a high temperature furnace.

7. The ultra-low pressure dynamic stability control high temperature hydrogen permeation test device according to claim 1, characterized in that: The closed-loop control unit includes a sensor group and a main control chip, and the sensor group includes a film gauge and a temperature detection sensor.

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