A material high-temperature hydrogen permeation simulation experiment device and method based on a counter-diffusion flame burner

Abstract

The application discloses a material high-temperature hydrogen permeation simulation experiment device and experiment method based on a counter diffusion flame burner. Fuel enters a fuel cavity with horizontal initial momentum, is discharged after the initial momentum is weakened, and oxidant is vertically discharged with an initial speed and is distributed above the fuel gas flow, so that the fuel and the oxidant form a speed difference, the oxidant can form an entrainment effect on the fuel, the mixing of the oxidant and the fuel is promoted, the stability and heat release efficiency of the counter diffusion flame are improved, sufficient combustion and uniformity of flame temperature distribution are ensured, efficient and uniform mixing can be realized without a swirl generator, the structure of the counter diffusion flame burner is simplified, the equivalence ratio of the oxidant and the fuel can be adjusted by a data acquisition and control system to adjust the combustion state of the flame, so that the flame height, the temperature and the active free radical concentration are accurately controlled, the application scene of a sample is effectively simulated, various flame environments can be provided for performance experiments of the sample, and the experimental reliability is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of material performance experiment, in particular to a material high-temperature hydrogen permeation simulation experiment device based on reverse diffusion flame burner. BACKGROUND

[0002] With the rapid development of hydrogen energy industry (such as hydrogen fuel cell, hydrogen storage tank, hydrogen pipeline, etc.), the long-term safety and reliability of key component materials under high pressure and high temperature hydrogen environment are facing severe challenges; hydrogen embrittlement as one of the main failure modes is a phenomenon that metal materials significantly decrease in plasticity and toughness due to hydrogen absorption and occur lagging fracture under static stress.

[0003] The commonly used hydrogen permeation test methods at present include electrochemical hydrogen charging method and high-pressure hydrogen tank static exposure method. The electrochemical hydrogen charging method introduces hydrogen atoms by cathodic hydrogen charging of electrolyte and then performs mechanical test, but it cannot simulate the real high-temperature gas-phase hydrogen environment. The high-pressure hydrogen tank method places the material in a high-pressure hydrogen tank for constant temperature exposure and then detects, which is closer to part of the working conditions, but it has problems of long cycle, complex equipment, high safety risk, and the static test method without heat source is difficult to reproduce the actual scene of high-temperature thermal cycle and dynamic hydrogen atmosphere coupling.

[0004] Further, the reverse diffusion flame refers to the combustion form formed by the fuel jet surrounding the oxidizer jet. Compared with the conventional diffusion flame, the reverse diffusion flame has the advantages of more sufficient mixing, higher heat release efficiency and cleaner combustion. The existing reverse diffusion flame burners mostly adopt coaxial ring structure, pass the oxidizer in the inner layer and pass the fuel in the outer layer, and often use a swirl structure to enhance the mixing. For example, the swirled reverse diffusion flame burner disclosed in the Chinese patent with the announcement number CN 208764920 U is provided with a special swirled flow generating chamber to make the fuel enter tangentially to form a swirl. However, the existing reverse diffusion flame burners are complex and have high manufacturing cost, and the flame flow field, temperature and concentration distribution generated thereby are difficult to truly simulate the high-temperature hydrogen environment of the material, and cannot be effectively used for high-temperature hydrogen permeation experiment.

[0005] Therefore, it has become a problem to be solved in the field to provide an experimental device which is simple in structure, can safely and truly simulate the high-temperature hydrogen environment, and realizes efficient and reliable hydrogen permeation test of the material. SUMMARY

[0006] In view of the defects of the prior art, the purpose of the present application is to provide a material high-temperature hydrogen permeation simulation experiment device and method based on reverse diffusion flame burner, which is simple in structure, good in simulation effect and safe and reliable.

[0007] In order to achieve the above-mentioned purpose, the material high-temperature hydrogen permeation simulation experiment device based on reverse diffusion flame burner provided by the present application comprises a reverse diffusion flame burner, a gas supply system, a sample fixing system and a data acquisition and control system,

[0008] The inverse diffusion flame burner is internally formed with an oxidant transition cavity and a fuel cavity, the oxidant transition cavity is distributed in the bottom region of the inverse diffusion flame burner and connected with an oxidant inlet pipe, the fuel cavity is distributed in the top region of the inverse diffusion flame burner and connected with a fuel inlet pipe, the top end of the fuel cavity is open to form a fuel exhaust port, and an oxidant exhaust pipe assembly is further arranged in the fuel cavity, one end of the oxidant exhaust pipe assembly is communicated with the oxidant transition cavity, and the other end extends out of the fuel cavity and is higher than the fuel exhaust port;

[0009] The fuel in the fuel inlet pipe enters the fuel cavity with horizontal initial momentum, forms a momentum weakening state in the fuel cavity, and is discharged from the fuel exhaust port, and the oxidant in the oxidant inlet pipe enters the oxidant transition cavity and forms a steady flow state in the oxidant transition cavity, and is vertically discharged along the oxidant exhaust pipe assembly at an initial speed, and is distributed above the fuel gas flow to form a speed difference with the fuel and to form an entrainment to the fuel;

[0010] The gas supply system is connected with the oxidant inlet pipe and the fuel inlet pipe respectively, and can deliver oxidant and fuel to the inverse diffusion flame burner;

[0011] The sample fixing system is distributed above the inverse diffusion flame burner, and is used for clamping and moving the sample to immerse the sample in different regions of the flame for experiment;

[0012] The data acquisition and control system can control the working state of the gas supply system, adjust the equivalence ratio of the oxidant and the fuel, adjust the flame state generated by the inverse diffusion flame burner, and can also monitor the surface temperature and hydrogen concentration of the sample in real time.

[0013] Further, the oxidant inlet pipe and the fuel inlet pipe are respectively horizontally distributed and connected with the oxidant transition cavity and the fuel cavity.

[0014] Further, the oxidant exhaust pipe assembly includes a center exhaust pipe and a plurality of peripheral exhaust pipes, the center exhaust pipe is arranged in the middle region of the fuel cavity, and the peripheral exhaust pipes are equidistantly arranged around the center exhaust pipe and jointly form an X-shaped distribution.

[0015] Further, the gas supply system includes a high-pressure air bottle and a high-pressure hydrogen bottle, the high-pressure air bottle is connected with the oxidant inlet pipe through a gas control valve and a gas mass flow controller, and the high-pressure hydrogen bottle is connected with the fuel inlet pipe through a gas control valve and a gas mass flow controller.

[0016] Further, the data acquisition and control system is connected with the gas control valve and the gas mass flow controller, and further comprises a thermocouple and a hydrogen sensor distributed above the counter-diffusion flame burner.

[0017] Further, the sample fixing system comprises an X-axis moving mechanism, a Y-axis moving mechanism and a Z-axis moving mechanism, the Z-axis moving mechanism is movable along the height direction of the sample fixing system, the X-axis moving mechanism is slidably arranged on the Z-axis moving mechanism and is movable along the axial direction of the Z-axis moving mechanism, and the Y-axis moving mechanism is slidably arranged on the X-axis moving mechanism and is movable along the radial direction of the X-axis moving mechanism.

[0018] Further, the Y-axis moving mechanism is provided with a sample fixing mechanism and a sensor expansion mounting groove.

[0019] Further, the counter-diffusion flame burner further comprises a protective gas inlet pipe, which can form a protective gas curtain around the periphery of the port of the counter-diffusion flame burner.

[0020] In order to achieve the above purpose, the material high-temperature hydrogen permeation simulation experiment method based on the counter-diffusion flame burner provided by the present application comprises the following steps:

[0021] Pre-experiment, the data acquisition and control system controls the working state of the gas supply system, adjusts the equivalence ratio of the oxidant and the fuel to perform pre-experiment, so as to determine the flame state of the experiment;

[0022] Formal experiment, the sample fixing system clamps the sample and moves the sample above the counter-diffusion flame burner, corresponding to the experimental area of the flame,

[0023] Ignition of the counter-diffusion flame burner, the fuel in the fuel inlet pipe enters the fuel cavity with a horizontal initial momentum, forms a momentum weakening state in the fuel cavity, and is discharged from the fuel exhaust port, the oxidant in the oxidant inlet pipe enters the oxidant transition cavity, forms a steady flow state in the oxidant transition cavity, and is vertically discharged along the oxidant exhaust pipe assembly at an initial speed, and is distributed above the fuel gas flow to form entrainment of the fuel,

[0024] At the same time, the sample is immersed in the experimental area of the flame, the data acquisition and control system monitors the surface temperature and hydrogen concentration of the sample in real time, adjusts the working state of the gas supply system to maintain the flame state, after the formal experiment is completed, the flame is extinguished, and the excess fuel is discharged through the fuel exhaust port.

[0025] The application provides a material high-temperature hydrogen permeation simulation experiment device based on a counter diffusion flame burner and an experiment method.

[0026] Moreover, the fuel cavity top end is open to form a fuel exhaust port, and excess fuel that is not combusted in time or does not participate in the reaction can diffuse into the atmosphere through the fuel exhaust port, preventing fuel accumulation inside the counter diffusion flame burner and improving experiment safety.

[0027] Further, the data acquisition and control system can adjust the equivalence ratio of the oxidizer and the fuel to adjust the combustion state of the flame, thereby accurately controlling the flame height, temperature and active free radical concentration, effectively simulating the application scenario of the sample, providing various flame environments for the performance experiment of the sample, and improving the experiment reliability. BRIEF DESCRIPTION OF DRAWINGS

[0028] The application is further described below in combination with the drawings and specific embodiments.

[0029] Figure 1 A system block diagram of the material high-temperature hydrogen permeation simulation experiment device based on the counter diffusion flame burner is provided.

[0030] Figure 2 A whole structure schematic diagram of the material high-temperature hydrogen permeation simulation experiment device based on the counter diffusion flame burner is provided.

[0031] Figure 3 A whole structure schematic diagram of the counter diffusion flame burner in the application is provided.

[0032] Figure 4 A top view schematic diagram of the counter diffusion flame burner in the application is provided.

[0033] Figure 5 A sectional view of the counter diffusion flame burner in the application is provided.

[0034] Figure 6 A structure schematic diagram of the sample fixing system in the application is provided.

[0035] Figure 7 A height curve schematic diagram of the flame under different equivalence ratios of the oxidizer and the fuel in the application is provided.

[0036] Figure 8Flame height diagram of different equivalence ratios when fuel flow is 3 SLM in the present application.

[0037] Figure 9 Mixing boundary diagram of oxidant and fuel under different fuel flow when equivalence ratio of oxidant and fuel is 1 in the present application.

[0038] Reference signs:

[0039] 1. Reverse diffusion flame burner; 11. Base; 12. Burner body; 13. Oxidant inlet pipe; 14. Fuel inlet pipe; 15. Oxidant transition cavity; 16. Fuel cavity; 17. Fuel exhaust port; 18. Oxidant exhaust pipe assembly; 181. Center exhaust pipe; 182. Peripheral exhaust pipe;

[0040] 2. Gas supply system; 21. High-pressure air bottle; 22. High-pressure hydrogen bottle; 23. Gas control valve; 24. Gas mass flow controller;

[0041] 3. Sample fixing system; 31. Fixing mounting frame; 32. X-axis moving mechanism; 33. Y-axis moving mechanism; 34. Z-axis moving mechanism; 35. Sample fixing mechanism; 36. Sensor expansion mounting slot;

[0042] 4. Data acquisition and control system; 41. Thermocouple; 42. Hydrogen sensor. DETAILED DESCRIPTION

[0043] In order to make the technical means, creative features, purposes and effects realized by the present application easy to understand, the present application is further described below in combination with specific drawings.

[0044] Referring to Figure 1 and Figure 2 , which shows one example of the material high-temperature hydrogen permeation simulation experimental device based on the reverse diffusion flame burner provided by the present application.

[0045] As can be seen from Figure 1 and Figure 2 , the material high-temperature hydrogen permeation simulation experimental device based on the reverse diffusion flame burner of the present example mainly comprises a reverse diffusion flame burner 1, a gas supply system 2, a sample fixing system 3 and a data acquisition and control system 4.

[0046] The inverse diffusion flame burner 1 can make the fuel enter with horizontal initial momentum, weaken the horizontal initial momentum, and then discharge, and the oxidant is vertically discharged with initial speed and is distributed above the fuel gas flow, so that the fuel and the oxidant form a speed difference, the oxidant can form an entrainment effect on the fuel, so as to promote the mixing of the oxidant and the fuel, improve the stability and heat release efficiency of the inverse diffusion flame, ensure the full combustion and uniformity of the flame temperature distribution, and at the same time, without the need of a swirl generator, high-efficiency and uniform mixing can be realized, and the structure of the inverse diffusion flame burner is simplified.

[0047] Further, the gas supply system 2 can transport the oxidant and the fuel to the inverse diffusion flame burner 1; the sample fixing system 3 is distributed above the inverse diffusion flame burner 1 and is used to clamp and move the sample, so as to immerse the sample in different regions of the flame for experiment; and the data acquisition and control system 4 can control the working state of the gas supply system 2, adjust the equivalence ratio of the oxidant and the fuel, adjust the flame state generated by the inverse diffusion flame burner 1, and can also monitor the surface temperature and hydrogen concentration of the sample in real time, so as to improve the safety and reliability of the experiment.

[0048] In combination Figures 3 to 5 Specifically, the inverse diffusion flame burner 1 comprises a base 11, a burner body 12, an oxidant inlet pipe 13 and a fuel inlet pipe 14, the burner body 12 is arranged on the base 11, and an oxidant transition cavity 15 and a fuel cavity 16 are further formed in the burner body 12.

[0049] The oxidant transition cavity 15 is distributed in the bottom region of the burner body 12 and is connected with the oxidant inlet pipe 13, the oxidant transition cavity 15 is transported with the oxidant through the oxidant inlet pipe 13, and the fuel cavity 16 is distributed in the top region of the burner body 12 and is connected with the fuel inlet pipe 14, the fuel cavity 16 is transported with the fuel through the fuel inlet pipe 14.

[0050] In addition, the oxidant inlet pipe 13 and the fuel inlet pipe 14 are respectively horizontally distributed and connected with the oxidant transition cavity 15 and the fuel cavity 16, so that the oxidant and the fuel are respectively horizontally transported into the oxidant transition cavity 15 and the fuel cavity 16.

[0051] Further, the top end of the fuel cavity 16 is completely open to form a fuel exhaust port 17, and an oxidant exhaust pipe assembly 18 is further arranged in the fuel cavity 16, one end of the oxidant exhaust pipe assembly 18 is communicated with the oxidant transition cavity 15, the other end of the oxidant exhaust pipe assembly 18 extends out of the top end of the fuel cavity 16 and is higher than the fuel exhaust port 17, so that the fuel in the fuel cavity 16 is diffused and discharged through the fuel exhaust port 17, and the oxidant in the oxidant transition cavity 15 is vertically discharged along the oxidant exhaust pipe assembly 18 and is distributed above the fuel gas flow.

[0052] In combination Figure 5Therefore, the fuel in the fuel inlet pipe 14 enters the fuel cavity 16 with horizontal initial momentum, and the fuel is subjected to air resistance in the semi-open fuel cavity 16 and collides with the inner wall of the fuel cavity 16. Under the joint action of air resistance and collision force, the horizontal initial momentum of the fuel is rapidly weakened, and the fuel is formed in a momentum weakening state in the fuel cavity 16 and moves and diffuses in the fuel cavity 16 at low speed based on the gravity of the fuel itself and faces the fuel exhaust port 17. Finally, the fuel is discharged from the fuel exhaust port 17, and a low-speed diffused fuel gas flow is formed around the fuel exhaust port 17.

[0053] Synchronously, the oxidant in the oxidant inlet pipe 13 horizontally enters the oxidant transition cavity 15, and the outlet of the oxidant in the oxidant transition cavity 15 is limited and cannot be rapidly discharged, so as to accumulate and form a stable pressure field in the oxidant transition cavity 15, so that the oxidant forms a steady flow state in the oxidant transition cavity 15 and is vertically discharged along the oxidant exhaust pipe assembly 18 to form a concentrated and high-speed oxidant gas flow.

[0054] Since the oxidant exhaust pipe assembly 18 extends out of the top end of the fuel cavity 16 and is higher than the fuel exhaust port 17, the high-speed oxidant gas flow is distributed above the low-speed fuel gas flow, and the oxidant and the fuel form a speed difference. The oxidant with a larger flow rate will form a smaller pressure, which will promote the fuel to move towards the oxidant, so that the oxidant produces an entrainment effect on the fuel, so as to realize the full mixing of the oxidant and the fuel, improve the stability and heat release efficiency of the counterflow diffusion flame, and ensure full combustion and uniformity of flame temperature distribution.

[0055] At the same time, the oxidant and the fuel form a “top-down” entrainment mixing mode, without the need for a complex swirl generator, so as to realize efficient and uniform mixing, thereby simplifying the structure of the counterflow diffusion flame burner 1.

[0056] In combination Figures 3 to 5 , in order to further improve the uniformity of flame combustion, the oxidant exhaust pipe assembly 18 includes a center exhaust pipe 181 and a peripheral exhaust pipe 182 which are equal in diameter and length, so that the flow and flow rate of the oxidant discharged from the center exhaust pipe 181 and the peripheral exhaust pipe 182 are kept consistent.

[0057] In addition, the center exhaust pipe 181 is arranged in the middle region of the fuel cavity 16, and the plurality of peripheral exhaust pipes 182 are equidistantly arranged around the center exhaust pipe 181 and collectively form an X-shaped distribution, so as to ensure the symmetry and uniformity of the outlet flow field of the oxidant gas flow, so that the flame shape is more stable and uniform, and a uniform and consistent high-temperature hydrogen environment is provided for the sample, so as to improve the experimental reliability.

[0058] Further, during the mixing and combustion of the oxidant and the fuel, the excess fuel that is not timely combusted or not involved in the reaction can be timely diffused into the atmosphere through the fuel exhaust port 17 at the top end of the fuel cavity 16, preventing the accumulation of fuel inside the counterflow diffusion flame burner 1 and improving the safety of the experiment.

[0059] In some embodiments, the counterflow diffusion flame burner 1 further comprises a protective gas inlet pipe arranged around the fuel exhaust port 17, which can transport inert protective gas (such as nitrogen, argon), thereby forming a protective gas curtain around the port of the counterflow diffusion flame burner 1, effectively isolating the interference of ambient air, ensuring the purity of the flame combustion, and also enabling rapid purging after the experiment is completed to extinguish the flame and protect the high-temperature sample, preventing oxidation of the sample due to contact with air, providing protection for subsequent experimental analysis, and ensuring the safety and reliability of the experiment.

[0060] The counterflow diffusion flame burner 1 thus formed can enable the oxidant to form a swirling action on the fuel, ensuring sufficient mixing of the oxidant and the fuel, thereby providing a uniform and stable high-temperature hydrogen environment for the sample.

[0061] In combination Figure 2 , further, the gas supply system 2 is connected to the oxidant inlet pipe 13 and the fuel inlet pipe 14 of the counterflow diffusion flame burner 1, respectively, and can stably transport the oxidant and the fuel to the counterflow diffusion flame burner 1.

[0062] Specifically, the gas supply system 2 includes a high-pressure air bottle 21 and a high-pressure hydrogen bottle 22, which are connected to the oxidant inlet pipe 13 and the fuel inlet pipe 14, respectively, and are provided with a gas control valve 23 and a gas mass flow controller 24 on the connecting pipeline, to transport air and hydrogen to the oxidant inlet pipe 13 and the fuel inlet pipe 14, so that the flame generated by the counterflow diffusion flame burner 1 forms a high-temperature hydrogen environment.

[0063] In coordination therewith, the data acquisition and control system 4 is connected to the gas control valve 23 and the gas mass flow controller 24, which can control the working state of the gas control valve 23 to respectively shut off the connecting pipeline between the high-pressure air bottle 21 and the high-pressure hydrogen bottle 22 and the oxidant inlet pipe 13 and the fuel inlet pipe 14, and start and stop the supply of the oxidant and the fuel, thereby controlling the combustion and extinguishing of the flame in the counterflow diffusion flame burner 1.

[0064] Further, the data acquisition and control system 4 can also control the working state of the gas mass flow controller 24 to adjust the delivery flow of the oxidant and the fuel respectively, and by adjusting the equivalence ratio (flow ratio) of the oxidant and the fuel, the flame combustion state can be changed, so as to accurately control the position of the high-temperature region in the flame, the temperature distribution, and the generation type and concentration of active free radicals, so as to simulate different chemical activity high-temperature hydrogen environments and application scenarios of the sample, and provide multiple flame environments for performance experiments of the sample, and improve the reliability of the experiments.

[0065] In combination Figure 2 and Figure 6 , the experimental device also includes a sample fixing system 3 distributed above the counter-diffusion flame burner 1, which is used to clamp and move the sample, and according to the experimental requirements, the sample is immersed in different regions of the flame (such as the flame core, the reducing flame, or the oxidizing flame region) for experiments.

[0066] Specifically, the sample fixing system 3 includes a fixed mounting rack 31 suspended or fixed above the counter-diffusion flame burner 1, and the fixed mounting rack 31 is respectively provided with an X-axis moving mechanism 32, a Y-axis moving mechanism 33, and a Z-axis moving mechanism 34, so that the X-axis moving mechanism 32, the Y-axis moving mechanism 33, and the Z-axis moving mechanism 34 cooperate to form a three-dimensional moving platform, which can drive the sample to move freely and ensure that the sample can be accurately immersed in the flame.

[0067] The Z-axis moving mechanism 34 is slidingly arranged in a vertical sliding rail of the fixed mounting rack 31 and can move along the height direction of the fixed mounting rack 31, and the Z-axis moving mechanism 34 is provided with an axial sliding rail, the X-axis moving mechanism 32 is sleeved on the Z-axis moving mechanism 34 and is slidingly connected with the axial sliding rail of the Z-axis moving mechanism 34, and can move along the axial direction of the Z-axis moving mechanism 34, and the bottom end of the X-axis moving mechanism 32 is further provided with a radial sliding rail, and the Y-axis moving mechanism 33 is slidingly arranged on the radial sliding rail and can move along the radial direction of the X-axis moving mechanism 32.

[0068] Further, the Y-axis moving mechanism 33 is provided with a sample fixing mechanism 35, which can be composed of a high-temperature-resistant ceramic or metal clamp to stably clamp the sample, so that the three-dimensional moving platform formed by the X-axis moving mechanism 32, the Y-axis moving mechanism 33, and the Z-axis moving mechanism 34 can stably drive the sample to move freely, and ensure that the sample can be accurately immersed in the flame, and according to the experimental requirements, the sample can be immersed in different regions of the flame (such as the flame core, the reducing flame, or the oxidizing flame region) for experiments.

[0069] In some embodiments, the Y-axis moving mechanism 33 is further provided with a sensor expansion mounting groove 36 close to the sample fixing mechanism 35, which is used to install temperature sensors, hydrogen concentration sensors, etc., to monitor the experimental state of the sample in the flame in real time.

[0070] The sample fixing system 3 thus formed can stably clamp and move the sample, ensure stable cooperation of the sample with the high-temperature hydrogen environment provided by the counter diffusion flame burner 1, and improve experimental reliability.

[0071] In combination Figure 2 In combination, the data acquisition and control system 4 further comprises thermocouples 41 and hydrogen sensors 42 distributed above the counter diffusion flame burner 1, in this example, the thermocouples 41 and the hydrogen sensors 42 are close to the sample and distributed on both sides of the sample, so as to monitor the surface temperature and hydrogen concentration of the sample immersed in the flame in real time, and based on this, the gas mass flow controllers 24 on the high-pressure air cylinder 21 and the high-pressure hydrogen cylinder 22 are adjusted in real time, so as to adjust the equivalence ratio of the oxidizer and the fuel, and ensure that the flame state remains stable.

[0072] The counter diffusion flame burner-based material high-temperature hydrogen permeation simulation experiment device is thus formed.

[0073] The application also provides a counter diffusion flame burner-based material high-temperature hydrogen permeation simulation experiment method, based on the above experiment device, the experiment method comprises:

[0074] First, pre-experiment inspection is performed, the data acquisition and control system 4 opens the gas control valves 23 on the high-pressure air cylinder 21 and the high-pressure hydrogen cylinder 22, and ensures the airtightness of the connection between the counter diffusion flame burner 1 and the gas supply system 2.

[0075] Next, pre-experiment is performed, the data acquisition and control system 4 adjusts the gas mass flow controllers 24 on the high-pressure air cylinder 21 and the high-pressure hydrogen cylinder 22, so as to adjust the equivalence ratio of the oxidizer and the fuel, determine the flame state and duration required for the experiment, and set the flow preset value of the oxidizer and the fuel.

[0076] Further, formal experiment is performed, the sample fixing system 3 clamps the sample, and moves the sample through cooperation of the X-axis moving mechanism 32, the Y-axis moving mechanism 33 and the Z-axis moving mechanism 34, so as to ensure that the sample can be accurately immersed in the experimental area of the flame.

[0077] Next, the counter diffusion flame burner 1 is ignited, for safety consideration, the ignition source is close to the oxidizer exhaust pipe assembly 18, the data acquisition and control system 4 first controls the gas mass flow controller 24 of the high-pressure hydrogen cylinder 22, so as to ensure that the hydrogen flow reaches the preset value, after hearing the "bang" sound and observing the generation of the flame, the ignition source is removed, and then the gas mass flow controller 24 of the high-pressure air cylinder 21 is controlled, so as to adjust the oxidizer flow to reach the preset value.

[0078] Therefore, the fuel in the fuel inlet pipe 14 enters the fuel cavity 16 of the counter-diffusion flame burner 1 with horizontal initial momentum, forms a momentum weakening state in the fuel cavity 16, and is discharged from the fuel exhaust port 17 at low speed. The oxidant in the oxidant inlet pipe 13 enters the oxidant transition cavity 15 and forms a steady flow state in the oxidant transition cavity 15, and is discharged vertically along the oxidant exhaust pipe assembly 18 at an initial speed, and is distributed above the fuel gas flow to form entrainment of the fuel, ensuring sufficient combustion and uniformity of flame temperature distribution.

[0079] At the same time, the sample is immersed in the experimental area of the flame, the data acquisition and control system 4 monitors the surface temperature and hydrogen concentration of the sample in real time, and adjusts the gas mass flow controller 24 on the high-pressure air bottle 21 and the high-pressure hydrogen bottle 22 in real time based on this to adjust the equivalence ratio of the oxidant and the fuel, and ensure that the flame state remains stable.

[0080] After the formal experiment is completed, the high-temperature sample is cooled and stored in an inert atmosphere protection box, the data acquisition and control system 4 closes the gas control valve 23 on the high-pressure air bottle 21 and the high-pressure hydrogen bottle 22, and the flame is extinguished. The excess fuel is discharged through the fuel exhaust port 17.

[0081] The following illustrates the working process of the application in a specific application. It should be noted that the content described herein is only a specific application example of the present application and does not limit the present application.

[0082] Taking the distance between the oxidant exhaust pipe assembly 18 and the fuel exhaust port 17 as 1 cm as an example, the vertical speed of the fuel moving to the top of the oxidant exhaust pipe assembly 18 can be calculated according to the Archimedes buoyancy law and Newton's second law , and the calculation formula is:

[0083] ;

[0084] In the formula, is the density of air (oxidant); is the density of fuel (hydrogen); is the acceleration of gravity; is the vertical speed of the fuel moving to the top of the oxidant exhaust pipe assembly 18; and s is the distance of the fuel moving to the top of the oxidant exhaust pipe assembly 18.

[0085] In this example, hydrogen is used as fuel, and the calculation shows that in the ideal case where air resistance is ignored, , and the fuel in the fuel cavity 16 will be affected by air resistance factors, so the vertical speed of the fuel will be in the range of , which is much smaller than the speed in the ideal case, so the horizontal initial momentum of the fuel is weakened, and the fuel forms a momentum weakening state in the fuel cavity 16 and then moves and diffuses towards the fuel exhaust port 17.

[0086] In this example, air is used as the oxidant. When the flow rate of air is , the vertical velocity of air exiting the oxidant exhaust assembly 18 at normal temperature and pressure is calculated to be approximately At this point, the air and fuel have formed a significant velocity difference, and as the flow rate of air increases, the velocity difference between the air and fuel increases linearly, causing the oxidant to effectively entrain the fuel, resulting in a more uniform mixture of oxidant and fuel.

[0087] Further, the data acquisition and control system 4 adjusts the gas mass flow controllers 24 on the high-pressure air cylinder 21 and the high-pressure hydrogen cylinder 22 to adjust the equivalence ratio of the oxidant and fuel, thereby adjusting the flame state, as shown in Figure 7 , which shows the height curve of the flame at different equivalence ratios of the oxidant and fuel, is the equivalence ratio of the oxidant and fuel, indicating the ratio of the actual fuel to oxidant to the theoretical stoichiometric ratio, is the inverse of , i.e., the air consumption coefficient, which is different at different equivalence ratios.

[0088] At the same air consumption coefficient, the greater the gas flow rate (SLM) of the oxidant and fuel, the higher the flame height (e.g., the flame height of 4 SLM is always much higher than that of 1 SLM), and at the same gas flow rate, the flame height generally decreases as the air consumption coefficient increases.

[0089] Referring to Figure 8 , Q H2 represents the flow rate of the fuel (hydrogen), represents the air consumption coefficient, which is different at different equivalence ratios, and it shows the flame height at different air consumption coefficients when the fuel (hydrogen) flow rate is 3 SLM, as shown in Figure 8 , when the fuel flow rate is 3 SLM, the flame height decreases as the air consumption coefficient increases.

[0090] Therefore, the data acquisition and control system 4 can adjust the delivery flow rate of the oxidant and fuel, change the flame burning state by adjusting the equivalence ratio of the oxidant and fuel, simulate different high-temperature hydrogen environments and application scenarios of the sample, provide multiple flame environments for performance experiments of the sample, and improve the reliability of the experiments.

[0091] Further, referring to Figure 9 , which shows the mixing boundary of the oxidant and fuel at different fuel (hydrogen) flow rates when the air consumption coefficient of the oxidant and fuel is 1, and Figure 9As shown, h is the fully mixed region of oxidant and fuel, below which the oxidant and fuel are not fully mixed, and the fully mixed region of oxidant and fuel has a height of 1.312 cm when the fuel (hydrogen) flow rate is 1 L / min, thus the reverse diffusion flame burner 1 can realize the entrainment of oxidant to fuel, promote the fully mixed of oxidant and fuel, and thus ensure the full combustion and the uniformity of flame temperature distribution.

[0092] The reverse diffusion flame burner-based material high-temperature hydrogen permeation simulation experiment device and experiment method provided by the present application can realize the efficient and uniform mixing without the need of a swirl generator, and thus simplifies the structure of the reverse diffusion flame burner 1.

[0093] Further, the data acquisition and control system 4 can adjust the equivalence ratio of the oxidant and fuel to adjust the combustion state of the flame, so as to accurately control the flame height, temperature and active free radical concentration, effectively simulate the application scene of the sample, and also provide various flame environments for the performance experiment of the sample, and improve the reliability of the experiment.

[0094] The basic principle, main features and advantages of the present application are shown and described above. It should be understood by those skilled in the art that the present application is not limited by the above examples, and the above examples and descriptions in the specification are only to illustrate the principle of the present application, and various changes and improvements can be made without departing from the spirit and scope of the present application, and these changes and improvements all fall within the scope of the present application. The scope of protection of the present application is defined by the appended claims and their equivalents.

Claims

1. A material high-temperature hydrogen permeation simulation experimental device based on a counter-diffusion flame burner, characterized in that, The device comprises a counterflow diffusion flame burner, a gas supply system, a sample fixing system and a data acquisition and control system, The counterflow diffusion flame burner is internally formed with an oxidant transition cavity and a fuel cavity, the oxidant transition cavity is distributed in the bottom region of the counterflow diffusion flame burner and is connected with an oxidant inlet pipe, the fuel cavity is distributed in the top region of the counterflow diffusion flame burner and is connected with a fuel inlet pipe, the top end of the fuel cavity is open to form a fuel exhaust port, and an oxidant exhaust pipe assembly is further arranged in the fuel cavity, one end of the oxidant exhaust pipe assembly is communicated with the oxidant transition cavity, and the other end of the oxidant exhaust pipe assembly extends out of the fuel cavity and is higher than the fuel exhaust port; The fuel in the fuel inlet pipe enters the fuel cavity with horizontal initial momentum, forms a momentum weakening state in the fuel cavity, and is discharged from the fuel exhaust port, the oxidant in the oxidant inlet pipe enters the oxidant transition cavity, forms a steady flow state in the oxidant transition cavity, is vertically discharged along the oxidant exhaust pipe assembly at an initial speed, and is distributed above the fuel gas flow to form a speed difference with the fuel and to form an entrainment to the fuel; The gas supply system is connected with the oxidant inlet pipe and the fuel inlet pipe respectively, and can transport oxidant and fuel to the counterflow diffusion flame burner; The sample fixing system is distributed above the counterflow diffusion flame burner, and is used for clamping and moving the sample to immerse the sample in different regions of the flame for experiment; The data acquisition and control system can control the working state of the gas supply system, adjust the equivalence ratio of the oxidant and the fuel, adjust the flame state generated by the counterflow diffusion flame burner, and can also monitor the surface temperature and hydrogen concentration of the sample in real time.

2. The material high temperature hydrogen permeation simulation experimental apparatus based on inverse diffusion flame burner according to claim 1, characterized in that, The oxidant inlet pipe and the fuel inlet pipe are horizontally distributed and connected with the oxidant transition cavity and the fuel cavity respectively.

3. The material high temperature hydrogen permeation simulation experimental apparatus based on inverse diffusion flame burner according to claim 1, characterized in that, The oxidant exhaust pipe assembly comprises a central exhaust pipe and a plurality of peripheral exhaust pipes, the central exhaust pipe is arranged in the middle region of the fuel cavity, and the peripheral exhaust pipes are equidistantly arranged around the central exhaust pipe and jointly form an X-shaped distribution.

4. The material high temperature hydrogen permeation simulation experimental apparatus based on inverse diffusion flame burner according to claim 1, characterized in that, The gas supply system comprises a high-pressure air bottle and a high-pressure hydrogen bottle, the high-pressure air bottle is connected with the oxidant inlet pipe through a gas control valve and a gas mass flow controller, and the high-pressure hydrogen bottle is connected with the fuel inlet pipe through a gas control valve and a gas mass flow controller.

5. The material high temperature hydrogen permeation simulation experimental apparatus based on inverse diffusion flame burner according to claim 4, characterized in that, The data acquisition and control system is connected with the gas control valve and the gas mass flow controller, and further comprises a thermocouple and a hydrogen sensor which are distributed above the counterflow diffusion flame burner.

6. The inverse diffusion flame burner based material high temperature hydrogen permeation simulation experimental apparatus according to claim 1, characterized in that, The sample fixing system comprises an X-axis moving mechanism, a Y-axis moving mechanism and a Z-axis moving mechanism, the X-axis moving mechanism, the Y-axis moving mechanism and the Z-axis moving mechanism cooperatively form a three-dimensional moving platform and can drive the sample to move.

7. The material high temperature hydrogen permeation simulation experimental apparatus based on inverse diffusion flame burner according to claim 6, characterized in that, The Y-axis moving mechanism is provided with a sample fixing mechanism and a sensor expansion installation slot.

8. The inverse diffusion flame burner based material high temperature hydrogen permeation simulation experimental apparatus according to claim 1, characterized in that, The counterflow diffusion flame burner further comprises a protective gas inlet pipe, and the protective gas inlet pipe can form a protective gas curtain outside the port of the counterflow diffusion flame burner.

9. The experimental method of the material high temperature hydrogen permeation simulation experimental apparatus based on inverse diffusion flame burner according to any one of claims 1-8, characterized in that, The experimental method comprises: Pre-experiment, the data acquisition and control system controls the working state of the gas supply system, adjusts the equivalence ratio of the oxidant and the fuel to carry out pre-experiment, so as to determine the flame state of the experiment; Formal experiment, the sample fixing system clamps the sample and moves the sample to above the counter diffusion flame burner, and corresponds to the experimental area of the flame; Ignite the counter diffusion flame burner, the fuel in the fuel inlet pipe enters the fuel cavity with horizontal initial momentum, forms a momentum weakening state in the fuel cavity, and is discharged from the fuel exhaust port, the oxidant in the oxidant inlet pipe enters the oxidant transition cavity, forms a steady flow state in the oxidant transition cavity, is vertically discharged along the oxidant exhaust pipe assembly at an initial speed, and is distributed above the fuel gas flow to form entrainment to the fuel, At the same time, the sample is immersed in the experimental area of the flame, the data acquisition and control system monitors the surface temperature and hydrogen concentration of the sample in real time, adjusts the working state of the gas supply system, maintains the flame state, and after the formal experiment is completed, the flame is extinguished, and the excess fuel is discharged through the fuel exhaust port.

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