Experimental device and experimental method for testing explosion resistance performance of vortex wave flow resistance fire system

Abstract

The application discloses a vortex wave flow resistance fire resistance performance test experimental device and method, and the device comprises a visual square explosion pipeline, a vortex wave impedance type attenuation cavity system, a fire resistance system, an adjustable high-pressure ignition system, a high-frequency response explosion suppression system, a high-precision gas distribution system and a multi-parameter acquisition system. The device can realize visual research on the deflagration-to-detonation transition of non-uniform concentration gradient hydrogen, control the flame propagation speed and shock wave intensity entering the attenuation cavity, optimize the structure parameters of the attenuation cavity and establish an explosion parameter theoretical attenuation model. Through the change rule of the explosion resistance characteristics of the fire resistance device under multiple parameters, a quantitative relationship between the shock wave, flame propagation attenuation and the structure parameters of the fire resistance device is established, and quantitative analysis is conducted on the explosion resistance performance of the fire resistance device, the attenuation efficiency of the attenuation cavity and the quenching mechanism. The application fills the technical gaps in the deflagration-to-detonation transition mechanism of hydrogen under non-uniform concentration gradient, the flame and shock wave coupling attenuation mechanism and the quantitative characterization of the fire resistance device with multiple structure parameters.

Description

Technical Field

[0001] This invention belongs to the field of combustible gas explosion safety technology, and in particular relates to an experimental device and method for testing the explosion-proof performance of a vortex current flame arrestor system. Background Technology

[0002] In the fields of petroleum, chemical, mining, natural gas transmission and distribution, and new energy storage and transportation such as hydrogen energy, the explosive propagation of flammable gases in pipelines is one of the main causes of major safety accidents. As a core safety device for blocking flames and suppressing the spread of explosions, the accurate evaluation and reliability verification of the performance of flame arresters directly affect the intrinsic safety level of industrial systems. Currently, research on the explosion-proof performance of flame arresters largely relies on standardized explosion test pipelines. Common devices typically consist of a straight pipe section, a gas distribution system, an ignition unit, and a basic data acquisition system (such as pressure sensors and thermocouples), enabling basic verification of the static flame-proofing performance of flame arresters under uniform premixed gas conditions. Some advanced systems have introduced visualization technologies such as high-speed photography and infrared thermal imaging to observe the macroscopic morphology and propagation process of flames; in the study of attenuation mechanisms, design attempts have emerged using simple expansion cavities, porous materials, or corrugated structures to weaken flames and pressure waves.

[0003] However, with the increasing complexity of industrial environments and the raising of safety standards, existing testing technologies and devices are increasingly revealing significant limitations in terms of scientific rigor, comprehensiveness, and practicality. Firstly, their ability to simulate operating conditions is insufficient. Most tests are conducted only in ideal gases with uniform concentration, normal pressure, and normal temperature, failing to realistically reproduce the complex, non-uniform operating conditions commonly encountered in industrial settings, such as concentration gradients, stratified distributions, and high temperatures and pressures. They also lack stable, continuous, and adjustable flame acceleration mechanisms, making it difficult to cover the complete explosion evolution spectrum from low-speed deflagration to high-speed detonation, resulting in a disconnect between test conditions and real accident scenarios. Secondly, their detection dimensions are singular, and their mechanism revelation remains superficial. Traditional methods mainly rely on point measurements of macroscopic physical quantities such as pressure and temperature, lacking synchronous, high-frequency, and in-situ detection capabilities for key microscopic chemical information (such as free radical concentration and active particle distribution) and transient physical fields (such as turbulent structure and temperature field evolution) during flame propagation and quenching. This means that the core processes in the flame arrester's "quenching mechanism" (such as the wall effect, heat transfer efficiency, and free radical destruction kinetics) remain largely at the theoretical speculation level, lacking direct, quantitative experimental data support. Third, the system suffers from low integration and modularity, making it inconvenient to replace flame arrester samples and attenuation structures, and resulting in low efficiency in comparing different parameters. Various sensors and control systems often operate independently, leading to poor signal synchronization and data integration difficulties, resulting in inconsistent and uncomparable experimental results. Fourth, the safety redundancy design is weak, lacking proactive, rapid, and automated explosion suppression protection and exhaust gas treatment mechanisms during experiments, posing safety hazards and environmental risks. Fifth, there is a lack of a quantitative correlation model between structure and performance. Existing research focuses primarily on phenomenon description and data recording, failing to establish a universal theoretical or semi-empirical model relating flame arrester geometric parameters, attenuation chamber structural characteristics, and explosion attenuation effects, thus hindering the precise design and performance optimization of flame arresters. Summary of the Invention

[0004] The purpose of this invention is to provide an experimental device and method for testing the explosion-proof performance of a vortex current flame arrestor system, aiming to construct a highly integrated, multi-dimensional sensing, programmable, safe, and controllable comprehensive explosion-proof research platform. This device achieves precise and continuous control of the flame state from deflagration to detonation through an innovative adjustable multi-segment spiral flame acceleration system; it integrates a multi-dimensional synchronous acquisition system including high-frequency pressure / temperature sensors, flame ion probes, gas concentration monitoring, high-speed imaging, and infrared thermal imaging, enabling coordinated observation of the macroscopic dynamics and microscopic chemical processes of explosion propagation; it employs a modularly designed visualized square flame arrestor system and a parameterized vortex impedance attenuation cavity, supporting rapid replacement and comparative testing of different flame arrestor units and attenuation configurations; and it is equipped with a high-frequency response explosion suppression system based on rapid signal triggering and a programmed full-process control, ensuring a high degree of automation and intrinsic safety in the experimental process. Based on the high-fidelity, multi-dimensional experimental data obtained by this device, a theoretical model of the attenuation of explosion flames and shock waves in complex structures can be further established, and empirical formulas between key quenching parameters of flame arresters (such as critical quenching length, temperature, and velocity) and their structural parameters can be derived. This will systematically overcome the shortcomings of existing testing technologies in terms of operational realism, mechanism depth, system flexibility, and engineering guidance, and provide key technical support and experimental basis for the research and development, standard setting, and engineering application of a new generation of high-performance flame arresters.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: An experimental device for testing the explosion-proof performance of a vortex current flame arrestor system includes: a visualized square explosion duct, a vortex impedance attenuation cavity system, a visualized square flame arrestor system, an adjustable high-pressure ignition system, a high-frequency response explosion suppression system, a high-precision gas distribution system, a flame acceleration device, a multi-dimensional parameter acquisition system, a program control and data acquisition system, and a synchronization controller. The program control and data acquisition system, through the synchronization controller, establishes signal connections with the adjustable high-pressure ignition system, the high-frequency response explosion suppression system, the high-precision gas distribution system, the flame acceleration device, and the multi-dimensional parameter acquisition system, respectively, to achieve time-series coordinated control of each system and synchronous acquisition, storage, and analysis of test data. The multi-dimensional parameter acquisition system integrates functions for flame arrestor core temperature acquisition, high-frequency pressure acquisition, high-frequency temperature acquisition, flame ion concentration acquisition, gas concentration monitoring, and flame morphology acquisition.

[0006] Further optimization involves a biaxially symmetrical cavity structure comprising two coaxially arranged circular pipes with expanding spherical surfaces, denoted as the outer pipe and the inner pipe, with a gap between them. The outer pipe, along its length, sequentially includes a first horizontal section, a first corner section, a first bend section, another corner section, and a first horizontal section, with the radius of the first bend section being larger than that of the first horizontal section. The inner pipe, along its length, sequentially includes a diversion section, a second horizontal section, a second corner section, a second bend section, another corner section, a second horizontal section, and a diversion section, with the radius of the second bend section being larger than that of the second horizontal section. The inner pipe is nested within the outer pipe and is fixedly connected to it via a rigid support. Uniform through holes are provided on the pipe wall of the first bend section near the visual square fire arrestor system. Flanges are welded to both ends of the outer pipe, connecting it to the visual detonation section pipe and the visual square fire arrestor system, respectively. Thermocouples and pressure sensors are installed at both ends of the outer pipe near the flanges.

[0007] Further optimization is needed. The essence of reducing flame temperature is the dissipation of heat energy. The main pathways include: 1) heat conduction / convection: flame heat is dissipated through the metal wall; 2) cooling by work: gas expansion does work on the outside, reducing internal energy (adiabatic expansion); 3) turbulent mixing: high-temperature gas mixes with low-temperature medium. The temperature attenuation rate of the vortex impedance attenuation cavity system for the explosion flame is shown in formula (1): ; (1) Wherein, ∆T / T1 is the temperature attenuation rate, ∆T=T2-T1, T1 is the temperature value measured by the thermocouple at the front end of the vortex impedance attenuation cavity, and T2 is the temperature value measured by the thermocouple at the rear end of the vortex impedance attenuation cavity; k1, k2, k3, k4 are weighting coefficients, all ranging from 0.01 to 0.5; L1 is the length of the first horizontal section, D1 is the diameter of the outer pipe inlet section, L2 is the length of the second horizontal section, D2 is the diameter of the inner pipe inlet section, R1 is the radius of curvature of the first bending section, R2 is the radius of curvature of the second bending section, φ is the porosity of the through hole in the first bending section, d is the diameter of the through hole, and X is the expansion ratio of the pipe; the front end is the end near the visualized detonation section pipe, and the rear end is the end near the visualized square fire arrestor system.

[0008] First item (horizontal length): This represents the length of the "flat path" that the flame needs to travel within the expansion chamber. The longer the path, the more heat is exchanged with the wall, and the more significant the cooling. Second item (curvature of the curved segment): This represents the degree of curvature of the channel. The greater the curvature (the larger the curvature value), the more violently the flame collides with the wall, and the better the cooling effect.

[0009] The third item (through-hole effect): This represents the effect of openings in the internal pipe. Porosity φ and pore size ratio. The larger the flame, the stronger the "leakage" effect from the inner pipe to the outer chamber, resulting in more thorough mixing and cooling.

[0010] The fourth term (area expansion ratio): X represents the degree of sudden expansion of the pipe cross-sectional area. The more drastic the area expansion, the more significant the cooling effect of flame expansion. The reason for the absence of roughness: In high-speed turbulent flow, the convective heat transfer coefficient is insensitive to microscopic roughness; its influence is far less than that of macroscopic geometry (length, curvature) and flow state (jet, expansion). Its effect is already implicit in the empirical coefficients.

[0011] The essence of the pressure reduction in an explosion is the dissipation of mechanical energy (pressure energy, kinetic energy). The main pathways are flow resistance, including: 1) shape resistance: abrupt changes in cross-section and turns leading to flow separation and vortices; 2) frictional resistance: friction between the fluid and the wall; 3) throttling loss: local pressure drop when passing through a small orifice. The pressure attenuation rate of the vortex impedance attenuation cavity system for the explosion flame is shown in formula (2): ; (2) Wherein, ∆P / P1 is the pressure attenuation rate, ∆P=P2-P1, P1 is the pressure value measured by the pressure sensor at the front end of the eddy wave impedance attenuation cavity, and P2 is the pressure value measured by the pressure sensor at the rear end of the eddy wave impedance attenuation cavity; C1, C2, C3, and C4 are weighting coefficients, all ranging from 0.01 to 0.3; X is the expansion ratio of the pipe; α1 is the angle between the line connecting the beginning and end of the first corner segment and the horizontal direction; α2 is the angle between the line connecting the beginning and end of the second corner segment and the horizontal direction; S1 is the horizontal length of the first corner segment; S2 is the horizontal length of the second corner segment; and ε is the relative roughness of the pipe wall.

[0012] The first item (area expansion ratio): X, is the most important factor in pressure drop. When the cross-section suddenly expands, the pressure will drop sharply.

[0013] The second item (path complexity): This represents the degree to which the flame needs to turn. The larger the turning angle α and the longer the turning path S, the greater the energy loss and the greater the pressure drop.

[0014] The third item (through-hole effect): This represents the resistance encountered by the flame as it passes through the small orifice in the inner pipe. The larger the porosity φ and the length-to-diameter ratio L2 / D2 of the inner pipe, the more severe the pressure loss.

[0015] The fourth item (wall roughness): ε, relative roughness. The rougher the wall, the greater the friction and the greater the pressure loss.

[0016] The decrease in flame velocity is caused by two fundamental reasons: 1) Conservation of mass: as the cross-section expands, the flow velocity inevitably decreases; 2) Conservation of momentum: flow resistance consumes momentum, further decelerating the flame. The velocity attenuation rate of the vortex impedance attenuation cavity system for the explosion flame is shown in formula (3): (3) Where ∆V / V1 is the flame propagation velocity attenuation rate, ∆V = V2 - V1, V1 is the flame propagation velocity before entering the vortex impedance attenuation cavity, and V2 is the flame propagation velocity after passing through the vortex impedance attenuation cavity; M1, M2, M3, and M4 are weighting coefficients, all ranging from 0.05 to 0.5. The flame propagation velocity V1 before entering the vortex impedance attenuation cavity is calculated using a visualization tempered glass window mounted on the front of the vortex impedance attenuation cavity in conjunction with a high-speed camera; then, the flame propagation velocity V2 after passing through the vortex impedance attenuation cavity is calculated using a visualization tempered glass window mounted on the rear of the vortex impedance attenuation cavity in conjunction with a high-speed camera.

[0017] The first factor (area expansion ratio): X. This is the most important factor in deceleration; the more drastic the sudden expansion of the pipe cross-section (the greater the area expansion ratio), the more significant the deceleration effect of the flame expansion.

[0018] Second item (horizontal length): This represents the length of the "flat path" that the flame needs to travel within the expansion chamber. The longer the path (the larger the molecules), the more friction and heat exchange with the walls, and the more severe the velocity loss.

[0019] The third item (through-hole effect): The larger the porosity φ and the pore size ratio d / D2, the more energy leaks from the inner pipe, the more intense the internal flow field is stirred, and the more obvious the velocity decay.

[0020] Fourth item (total curvature): The curvature K represents the degree of curvature of the channel. The larger the curvature K value (i.e., the sharper the curve), the longer the turning path S, the more energy the flame is forced to change direction and generate a vortex, and the better the deceleration effect.

[0021] Further optimization includes a visual square flame arrestor system comprising a flame arrestor mounting housing and a replaceable corrugated flame arrestor. The upper panel, lower panel, and middle partition of the flame arrestor mounting housing are equipped with flame arrestor fixing structures. A sensor probe mounting hole is provided on the back panel, and a visual window connection structure is provided on the front. Flame arrestors are welded to both ends. The corrugated flame arrestor is detachably mounted in the flame arrestor mounting housing via a fixing structure, and the flame arrestor mounting housing is provided with flanges at both ends. Corrugated flame arrestors with different parameters are installed according to experimental needs, including the corrugation angle, corrugation height, material, and corrugation thickness of the corrugated flame arrestor.

[0022] Further optimization allows us to obtain the critical quenching temperature, critical quenching rate, critical quenching length, and critical quenching diameter of the flame based on the parameters of the corrugated flame arrester and the experimentally measured data. The formula for the critical quenching temperature is shown in formula (4). (4) Among them, T ext T is the critical extinction temperature. gas,min The base extinction temperature; E1, E2, and E3 are empirical coefficients, with E1 taking values ​​of (5-30), E2 taking values ​​of (1-20), and E3 taking values ​​of (0.5-10); n1, n2, and n3 are exponential coefficients, all taking values ​​of (0.5-2); δ is the corrugation thickness, and h is the corrugation height. λ is the corrugation angle, and λ is the friction coefficient.

[0023] The first term, Tgas,min, is the basic extinction temperature, determined by the inherent properties of the combustible gas (such as methane or hydrogen) and its initial concentration. It can be obtained through experiments without a flame arrester or in a large space. The second term (h / δ) is the core term, where δ represents the corrugation thickness and h represents the corrugation height. A smaller ratio means more metallic material relative to the channel size, resulting in stronger heat absorption and conduction capabilities, and faster flame cooling. Therefore, a higher initial temperature (Tgas,min) is required. ext (Raising the temperature) to maintain flame propagation. This is directly related to the "heat transfer effect". The third term (sinθ): θ is the angle between the corrugated slope and the base surface. As θ increases, the flow path becomes more tortuous, and turbulence is enhanced, which is beneficial for the mixing and heat exchange between the flame front and the cold wall surface, promoting quenching. Therefore, as θ increases, the required critical temperature T... ext It should also be increased. Use sinθ to monotonically increase it from 0 to 1 in the range of 0-90°. The fourth term (λ): As λ or surface roughness ε increases, flow resistance increases, turbulence intensity increases, and it may also increase the heat exchange efficiency near the wall. This is beneficial for flame quenching, and therefore will increase Text.

[0024] The formula for the critical quenching rate is shown in formula (5): ; (5) Among them, V ext V is the critical quenching rate. flame,0 For reference flame speed, F1, F2, and F3 are empirical coefficients, with F1 taking (1-5), F2 taking (0.5-3), and F3 taking (0.1-2); m1, m2, and m3 are exponential coefficients, all taking (0.5-2).

[0025] The first term (h / δ): δ is the corrugation thickness, and h is the corrugation height. A larger ratio means a wider channel and a thinner absorber, allowing the flame to pass through more easily. Therefore, V ext It will decrease. A smaller ratio indicates increased flame-retardant capability, Vext Increase. Second term (cosθ): θ is the ripple angle (as θ increases, cos θ decreases. Increasing θ makes the flow more tortuous, increasing the effective path length and resistance of flame propagation, which is beneficial for quenching high-speed flames. Therefore, when θ increases, Vext should decrease. cos θ decreases from 1 to 0 in the range of 0-90°). Third term (1+λ): λ is the friction factor (as λ increases, the flow resistance loss increases, more kinetic energy is converted into heat energy and dissipated through the wall, which is beneficial for reducing the flame speed until quenching. Therefore, when λ increases, Vext should increase, and (1+λ) is used to ensure a positive value).

[0026] The formula for the critical quenching length is shown in formula (6): ; (6) Among them, L ext For the quenching length, D h The hydraulic diameter is a key feature dimension for corrugated channels. For simple rectangular or triangular cross-sections, D... h It can be approximated as a function related to the ripple height h and the angle α. Initially, D can be used... h ∝ h. G1, G2, and G3 are empirical coefficients, with G1 taking (1-3), G2 taking (1-4), and G3 taking (0.2-2); p1, p2, and p3 are exponential coefficients, all taking (0.5-1.5).

[0027] The first term (h / δ): The larger this ratio, the wider the channel or the thinner the metal, the longer the flame needs to be cooled and quenched, thus increasing Lext. The second term (1 / (sin θ)): As θ increases, the flow becomes more tortuous, the flame makes more complete contact with the wall per unit axial length, and the quenching efficiency improves, therefore the required quenching length L... ext The lengthening of 1 / (sin θ) is consistent with the trend that θ increases. The third term (1+λ): as λ increases, turbulent mixing and energy dissipation intensify, potentially accelerating the quenching process and thus reducing L. ext Shorten. Therefore, as λ increases, this term in the formula should make L shorter. ext Decrease.

[0028] The formula for the critical quenching diameter is shown in formula (7): ; (7) Where, d c The critical quenching diameter is defined as the hydraulic diameter (or equivalent diameter) of the corrugated flame arrester channel, representing the maximum value at which the flame can be reliably quenched. g0The basic quenching diameter is determined by the inherent properties of the combustible gas (such as the molecular diffusion coefficient of methane and hydrogen, flame temperature, and free radical lifetime). It is usually related to the laminar flame quenching diameter of the gas in air and can be obtained through standard experiments or literature. H1, H2, and H3 are empirical coefficients, all taking values ​​of (0.2-3); q1, q2, and q3 are exponential coefficients, all taking values ​​of (0.5-2).

[0029] The first term (h / δ): This directly characterizes the heat transfer capacity. δ represents the corrugation thickness, and h represents the corrugation height. A larger ratio means a stronger "heat sink" effect of the metal relative to the channel, allowing it to absorb more heat from the flame. This enables the channel to quench the flame even at larger dimensions, thereby increasing the critical quenching diameter d. c This is one of the core advantages of corrugated flame arresters compared to simple flat plate gaps. The second term (sinθ): This term characterizes the tortuous flow path and enhanced turbulence. Increased θ results in a more tortuous flow path, producing stronger turbulent mixing and secondary flow. This enhances the following effects: Promotes heat exchange: Turbulence transports heat from the high-temperature core region to the cold wall surface more quickly. Strengthens free radical destruction: Increases the probability of free radicals colliding with the wall (wall effect). Therefore, increasing θ (increased sin θ) significantly enhances quenching efficiency, allowing for larger channel dimensions (larger d). c It can still effectively quench flames. The third term (λ): friction coefficient, which characterizes turbulent dissipation and near-wall effects. An increase in λ leads to: increased flow resistance, with more kinetic energy being converted into heat and dissipated through the wall. Enhanced near-wall turbulence, disrupting the laminar sublayer and making heat and mass exchange more intense. Absolute roughness itself reduces the effective flow area and generates more eddies. These effects synergistically enhance quenching capability, therefore an increase in λ should lead to an increase in dc.

[0030] Further optimization includes a second fixed support, two coaxially nested independent helical blade assemblies, and a drive assembly for adjusting the angle of the helical blades. The second fixed support is located inside the visible detonation section pipe and is close to one end of the adjustable high-pressure ignition system. The two independent helical blade assemblies are a first helical blade assembly and a second helical blade assembly. The first helical blade assembly includes a first motor, a first cylinder, a lead screw, and a first base. The second fixed support is fixedly connected to the first base, the first cylinder is rotatably connected to the first base via a bearing, the first motor is fixedly installed inside the first cylinder, the output shaft of the first motor is fixedly connected to one end of the lead screw, and first blades are helically arranged along the length of the outer wall of the first cylinder.

[0031] The second helical blade assembly includes a second cylinder and a second base. The second cylinder is rotatably connected to the second base via a bearing, and the second base is located on the side closer to the first motor. A threaded through hole is provided at the center of the second base, and the second base is sleeved on the lead screw through the threaded through hole at its end and threadedly connected to it. A first guide rail is provided along the length direction on the inner wall of the first cylinder, and a first slider is provided on the outer wall of the second base. The first slider is slidably locked on the first guide rail. A second blade is helically arranged along the length direction on the outer wall of the second cylinder. The helical diameter of the second helical blade assembly is smaller than the inner diameter of the first cylinder. The visualized detonation section pipe, the first cylinder, and the second cylinder are coaxially arranged. A limit block is provided at the end of the lead screw, and the length of the lead screw is greater than the length of the first cylinder.

[0032] The first blade shown includes multiple first blade units, all of which are spirally and integrally arranged on the first cylinder, with gaps and discontinuities between adjacent first blade units; the second blade shown includes multiple second blade units, all of which are spirally and integrally arranged on the second cylinder, with gaps and discontinuities between adjacent second blade units.

[0033] The drive assembly for adjusting the angle of the spiral blades includes a second motor and a third motor disposed outside the visible detonation section pipe. The shafts of the second and third motors extend into the visible detonation section pipe and are sealed to the pipe wall. A first bevel gear is fixedly mounted on the end of the shaft of the second motor, and a second bevel gear is fixedly mounted on the end of the shaft of the third motor. A first bevel gear ring is fixedly fitted on one end of the first cylinder near the fixed support, and a second bevel gear ring is fixedly fitted on one end of the second cylinder near the fixed support. The first bevel gear meshes with the first bevel gear ring. When the second cylinder is fully extended from the first cylinder, the second bevel gear meshes with the second bevel gear ring.

[0034] The first motor drives the lead screw to rotate, causing the second cylinder to extend out of the first cylinder, or the first motor reverses to retract the second cylinder into the first cylinder. The second motor drives the first bevel gear, causing the first cylinder and the first blade to rotate by a set angle. When the second cylinder is fully extended from the first cylinder, the second bevel gear meshes with the second bevel gear ring, and the third motor drives the second bevel gear, causing the second cylinder and the second blade to rotate by a set angle. By changing the length and angle of the blades, turbulent disturbances are generated in the flame, and the flame propagation speed is changed, realizing the simulation of the full acceleration process from deflagration to detonation. The first, second, and third motors are all servo motors, which are industrial-grade custom-made high-temperature liquid-cooled servo motors. The wires are made of mineral-insulated cables that can withstand high temperatures, and the cylinder is made of 316L thick-walled pressure-resistant stainless steel. The wires of the first motor are run through the cavity of the fixed bracket and out of the visible detonation section pipe to the outside for electrical connection with the control system.

[0035] Further optimization involves the visualization of a square explosion conduit, which includes a visualization detonation section conduit and a visualization protection section conduit arranged coaxially. One end of the visualization detonation section conduit is sealed and connected to a first square container with a visualization window via a flange; the other end of the visualization detonation section conduit is sealed and connected to one end of a vortex impedance attenuation cavity system via a flange, and is connected to the attenuation cavity of the vortex impedance attenuation cavity system.

[0036] One end of the visualized protection section pipe is sealed and connected to a second square container with a visualized viewing window via a flange; the other end of the visualized protection section pipe is sealed and connected to one end of the visualized square fire arrestor system via a flange; the other end of the visualized square fire arrestor system is sealed and connected to the other end of the eddy wave impedance attenuation cavity system via a flange, and is connected to the attenuation cavity of the eddy wave impedance attenuation cavity system. The walls of both the visualized detonation section pipe and the visualized protection section pipe are fitted with high-intensity visualized windows along their length for use with a multi-dimensional parameter acquisition system to observe flame propagation, quenching, and potential reignition processes.

[0037] Further optimization involves the adjustable high-voltage ignition system comprising an adjustable high-voltage igniter, a program control and data acquisition system, and a synchronization controller. The adjustable high-voltage igniter is coaxially mounted at the end of the first square container away from the visible detonation section pipe, with the ignition electrode located on the central axis of the visible detonation section pipe. Through the program control and data acquisition system and the synchronization controller, the discharge sequence, discharge duration, and ignition energy of the adjustable high-voltage igniter can be adjusted to adapt to combustible gases with different minimum ignition energies and to regulate the initial flame development state.

[0038] The high-frequency response explosion suppression system consists of a flame signal detector, a high-pressure fine nozzle, a high-pressure inhibitor storage tank, a solenoid valve, a program control and data acquisition system, and a synchronization controller. The flame signal detector is installed at the end of the pipeline in the visual protection section and is connected to the program control and data acquisition system and the synchronization controller. The high-pressure fine nozzle is installed in the pipeline downstream of the flame signal detector and is connected to the high-pressure inhibitor storage tank through the solenoid valve. When the flame arrestor fails, the trigger signal from the flame signal detector is fed back to the program control and data acquisition system through the synchronization controller, which in turn controls the solenoid valve to open, and the inert inhibitor is atomized and sprayed out through the high-pressure fine nozzle to extinguish the flame.

[0039] The high-precision gas distribution system consists of a flexible heating belt, a high-precision circulating gas distributor, a stratified airflow distributor, a micro mass flow controller, and a vacuum pump. The first square container and the visualized detonation section pipeline are equipped with multiple sets of air inlets, which work in conjunction with the stratified airflow distributor and the micro mass flow controller to achieve multi-position gas delivery. The high-precision circulating gas distributor is connected to the combustible gas source, the air source, and the visualized detonation section pipeline, respectively. The flexible heating belt is wrapped around the outer wall of the pipeline to regulate the initial gas temperature. Uniform premixed gas can be prepared by the vacuum pump and the high-precision circulating gas distributor, and non-uniform premixed gas can be prepared in conjunction with the stratified airflow distributor and the micro mass flow controller.

[0040] Further optimization includes the following multi-dimensional parameter acquisition system: a flame arrestor core temperature acquisition unit for acquiring flame arrestor core temperature, with its sensor integrated inside the flame arrester slit channel; a high-frequency pressure acquisition unit for acquiring pressure data, with its sensor deployed in the visualized detonation section pipeline, eddy wave impedance attenuation cavity, and visualized protection section pipeline; a high-frequency temperature acquisition unit for acquiring temperature data, with its sensor corresponding to the high-frequency pressure acquisition unit sensor and working in conjunction with a high-speed infrared thermal imager to acquire the macroscopic temperature of the flame; a flame ion concentration acquisition unit for acquiring flame ion concentration, with its probe deployed in the pipeline and flame arrester slit channel; a gas concentration monitoring unit for monitoring gas concentration, with its sensor deployed at different locations in the pipeline; and a flame morphology acquisition unit for capturing flame morphology, with its high-speed camera optically adapted to the visualized viewing window.

[0041] An experimental method for testing the explosion-proof performance of a vortex flow flame arrestor system based on the above-described device includes the following steps: Step S1. Device assembly and debugging: Select a corrugated flame arrestor with target parameters, assemble a visual square flame arrestor system, complete the sealed connection of the entire explosion pipeline link, and debug the function and airtightness of each system component; Step S2. Pipeline vacuuming: Evacuate the explosion pipeline and related systems to a preset vacuum state using a vacuum pump; Step S3. Premixed gas preparation and preheating: Prepare uniform or non-uniform premixed gas using a high-precision gas mixing system, and adjust the initial temperature and pressure of the gas; Step S4. Ignition and data acquisition: Trigger the adjustable high-pressure igniter with a synchronous controller to ignite, and simultaneously start the multi-dimensional parameter acquisition system to synchronously acquire parameter data of flame propagation, attenuation, quenching, and potential reignition processes; Step S5. Safety protection and exhaust gas treatment: After ignition, monitor the flame arrestor status with a flame signal detector, and trigger a high-frequency response explosion suppression system when the flame arrestor fails; After the experiment, wait for the exhaust gas to cool to room temperature, discharge the exhaust gas, and reset the device.

[0042] Compared with existing technologies, the beneficial effects of this invention are as follows: 1. This invention highly integrates systems such as high-precision gas distribution, adjustable ignition, flame acceleration, flame arrestor testing, and explosion suppression protection to construct a multifunctional experimental platform. In particular, the unique adjustable flame acceleration device combined with the vortex impedance attenuation cavity system can stably and controllably generate the flame propagation state from deflagration to detonation, greatly expanding the range of test conditions and making the test results closer to industrial reality. 2. The experimental device described in this invention integrates multiple types of sensors, including high-frequency pressure, high-frequency temperature, flame ion concentration, gas concentration, flame morphology (high-speed camera and infrared thermal imaging), and flame arrestor core temperature. It achieves precise synchronous triggering and high-speed acquisition of all signals through a unified program control and data acquisition system and a synchronous controller. This enables comprehensive and quantitative analysis of flame propagation characteristics, flame arrestor performance, and quenching mechanisms from multiple dimensions, from macroscopic to microscopic and from physical to chemical perspectives. The visualized square flame arrestor system supports rapid replacement of flame arrestor cores with different angles, heights, materials, and thicknesses, and the structural parameters of the vortex impedance attenuation cavity are also variable. This modular design enables researchers to systematically study the impact of single parameter changes on flame arrestor performance, providing a powerful experimental tool for optimizing flame arrester design. 3. By using a flame ionization probe and a K-type thermocouple positioned inside the flame arrester slit, key parameters during the quenching process can be directly measured. This provides unprecedented direct experimental data for quantitative analysis of core quenching mechanisms such as the "wall effect" and "heat transfer," overcoming the limitations of traditional indirect inferences based solely on external macroscopic parameters. 4. The experimental setup described in this invention is equipped with a high-frequency response explosion suppression system as an active safety barrier. This system can instantly activate and suppress the flame in the event of flame arrestor failure, ensuring the safety of the experimental process. The entire experimental process, from gas mixing, ignition, data acquisition to explosion suppression, is controlled collaboratively by a program control and data acquisition system with a synchronous controller. This significantly reduces human error and improves the repeatability, reliability, and efficiency of the experiment. Attached Figure Description

[0043] Figure 1 Schematic diagram of the experimental setup for testing and evaluating key technologies of vortex current flame arrestor system explosion-proof performance; Figure 2 This is a structural diagram of a vortex impedance attenuation cavity system. Figure 3 A schematic diagram illustrating the mechanism of vortex impedance attenuation cavity in attenuating explosion flames; Figure 4 A structural schematic diagram of the upper, lower, back plate, and middle partition of the square flame arrester housing; Figure 5 This is a schematic diagram illustrating the installation method of a flame arrester. Figure 6 A schematic diagram illustrating the installation method of a visual square flame arrester; Figure 7 Cross-sectional views of flame arresters with different structural parameters; Figure 8 This is a diagram showing the flame propagation structure of methane at different diffusion times. Figure 9The graph shows the relationship between methane free diffusion time and flame front velocity. Figure 10 This is a structural diagram of a flame acceleration device; Figure 11 A schematic diagram illustrating the installation method of a patch-type K-type armored thermocouple; Figure 12 This is a schematic diagram illustrating the installation method of the probe in the internal slit channel of a flame arrester. Detailed Implementation

[0044] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.

[0045] Example 1: Refer to Appendix Figure 1 The experimental device for testing the explosion-proof performance of the vortex flow flame arrestor system includes: a visualized square explosion pipeline, a vortex impedance attenuation cavity system, a visualized square flame arrestor system, an adjustable high-pressure ignition system, a high-frequency response explosion suppression system, a high-precision gas distribution system, a flame acceleration device, a flame arrestor core temperature acquisition system, a high-frequency pressure acquisition system, a high-frequency temperature acquisition system, a flame ion concentration acquisition system, a gas concentration monitoring system, a flame morphology acquisition system, a program control and data acquisition system, and a synchronous controller.

[0046] The program control and data acquisition system, combined with a synchronous controller, establishes signal connections with the adjustable high-pressure ignition system, high-frequency response explosion suppression system, high-precision gas distribution system, flame acceleration device, flame arrestor core temperature acquisition system, high-frequency pressure acquisition system, high-frequency temperature acquisition system, flame ion concentration acquisition system, gas concentration monitoring system, and flame morphology acquisition system, respectively, to achieve time-series coordinated control of each system and synchronous acquisition, storage, and analysis of test data.

[0047] The visualized square explosion conduit consists of a visualized detonation section conduit 2 and a visualized protection section conduit 3. The left end of the visualized detonation section conduit 2 is tightly connected to a first square container 1-1 equipped with a first visualized tempered glass window 4-1 via a flange, and the right end is tightly connected to a vortex impedance attenuation cavity 5 via a flange. A second visualized tempered glass window 4-2 is installed along the length of the wall of the visualized detonation section conduit 2. The right end of the visualized protection section conduit 3 is tightly connected to a second square container 1-2 equipped with a fourth visualized tempered glass window 4-4 via a flange, and the left end is tightly connected to a visualized square flame arrester 6 via a flange. A third visualized tempered glass window 4-3 is installed along the axial direction of the wall of the visualized protection section conduit 3. Through the visualized tempered glass window in conjunction with a high-speed camera 25, the flame propagation speed, dynamic propagation process, critical quenching speed, critical quenching length, and potential reignition phenomena of the flammable medium can be directly observed and recorded.

[0048] like Figure 2As shown, the eddy wave impedance attenuation cavity system is a biaxially symmetrical cavity structure, consisting of two coaxially arranged circular pipes with expanded spherical surfaces, denoted as outer pipe 5-1 and inner pipe 5-2, with a gap between them. The outer pipe, along its length, sequentially includes a first horizontal section, a first corner section, a first bend section, another corner section, and a first horizontal section, with the radius of the first bend section being larger than that of the first horizontal section. The inner pipe, along its length, sequentially includes a diversion section, a second horizontal section, a second corner section, a second bend section, another corner section, a second horizontal section, and a diversion section, with the radius of the second bend section being larger than that of the second horizontal section. The inner pipe is nested within the outer pipe and is fixedly connected to it via a rigid support. Uniform through holes 5-5 are provided on the pipe wall of the first bend section near the side of the visible square fire arrestor system.

[0049] Both ends of the outer pipe are welded with flanges, which connect to the visual detonation section pipe 2 and the visual square flame arrestor system, respectively. Probe holes and threaded holes 5-4 are opened on the outer pipe wall between the flanges and the fixed bracket 5-3. High-temperature thermocouples and high-frequency pressure sensors are installed above and below the pipe. The data obtained through measurement can directly reflect the attenuation effect of the vortex impedance attenuation cavity on the explosion flame. The vortex impedance attenuation cavity is tightly connected to the pipes on both sides through flanges, metal gaskets, and nuts on both sides to ensure the airtightness of the experimental device at the connection point.

[0050] The temperature attenuation rate of the eddy wave impedance attenuation cavity system for the explosion flame is shown in formula (1):

[0051] ; (1) Wherein, ∆T / T1 is the temperature decay rate, ∆T=T2-T1, T1 is the temperature value measured by the thermocouple at the front end of the vortex impedance attenuation cavity, and T2 is the temperature value measured by the thermocouple at the rear end of the vortex impedance attenuation cavity; k1, k2, k3, k4 are weighting coefficients, all of which are (0.01-0.5); L1 is the length of the first horizontal section, D1 is the diameter of the outer pipe inlet section, L2 is the length of the second horizontal section, D2 is the diameter of the inner pipe inlet section, R1 is the radius of curvature of the first bending section, R2 is the radius of curvature of the second bending section, φ is the porosity of the through hole on the first bending section, d is the diameter of the through hole, and X is the expansion ratio of the pipe; the front end is the end close to the visual detonation section pipe (2), and the rear end is the end close to the visual square fire arrestor system; The pressure attenuation rate of the vortex impedance attenuation cavity system for the explosion flame is shown in formula (2): ; (2) Wherein, ∆P / P1 is the pressure attenuation rate, ∆P=P2-P1, P1 is the pressure value measured by the pressure sensor at the front end of the eddy wave impedance attenuation cavity, and P2 is the pressure value measured by the pressure sensor at the rear end of the eddy wave impedance attenuation cavity; C1, C2, C3, and C4 are weighting coefficients, all ranging from 0.01 to 0.3; X is the expansion ratio of the pipe; α1 is the angle between the line connecting the beginning and end of the first corner segment and the horizontal direction; α2 is the angle between the line connecting the beginning and end of the second corner segment and the horizontal direction; S1 is the horizontal length of the first corner segment; S2 is the horizontal length of the second corner segment; and ε is the relative roughness of the pipe wall. The velocity attenuation rate of the vortex impedance attenuation cavity system for the explosion flame is shown in formula (3): (3) Where ∆V / V1 is the flame propagation velocity attenuation rate, ∆V=V2-V1, V1 is the flame propagation velocity before entering the vortex impedance attenuation cavity, and V2 is the flame propagation velocity after passing through the vortex impedance attenuation cavity; M1, M2, M3, and M4 are weighting coefficients, all of which are taken as (0.05-0.5).

[0052] The flame propagation speed V1 before entering the vortex impedance attenuation cavity is calculated using a high-speed camera and a visual tempered glass window mounted on the front of the vortex impedance attenuation cavity 5. Then, the flame propagation speed V2 after passing through the vortex impedance attenuation cavity is calculated using a high-speed camera and a visual tempered glass window mounted on the rear of the vortex impedance attenuation cavity 5.

[0053] like Figure 3 As shown, the specific mechanism by which the vortex impedance attenuation cavity attenuates explosion flames is as follows: Phase 1: Energy Reflection and Initial Attenuation Caused by Sudden Cross-Section Expansion. At the inlet interface where the explosion flame enters the vortex impedance attenuation cavity from the inner pipe, sudden cross-section expansion is the dominant initial condition. This geometrical abrupt change first leads to a sharp attenuation of the macroscopic propagation velocity of the flame, based on the law of conservation of mass. Simultaneously, based on the principle of acoustic impedance matching, the detonation wave accompanying the flame undergoes severe impedance mismatch at this interface, generating a significant series of incident shock waves, reflected shock waves, and expansion waves. The reflected shock wave carries a large amount of energy back upstream, directly weakening the peak overpressure of the transmitted wave, while the propagation of the expansion wave promotes isentropic expansion of the gas, synergistically achieving an initial reduction in static pressure and flame temperature.

[0054] The second stage: continuous dissipation due to energy dispersion and path extension. Immediately after the abrupt expansion, energy dispersion occurs in the flow field, with the core jet splitting into multiple sub-flows. This process significantly reduces the energy density per unit volume. Simultaneously, the different streams undergo path extension, meaning the contact time and interaction distance between the flame and the cavity wall increase. During this stage, the flow velocity continues to decrease due to energy dispersion, the pressure further decreases due to the spatial expansion effect, and the flame temperature continues to dissipate through wall heat exchange as the heat flow is dispersed over a larger surface area.

[0055] The third stage: Enhanced dissipation dominated by secondary vortices, flow separation, and through-hole jets. In the core dissipation region of the vortex impedance attenuation cavity, multiple efficient physical mechanisms are simultaneously activated. Secondary vortices and flow separation phenomena are widely generated, disrupting the stability of the mainstream and consuming mechanical energy. Crucially, the system generates strong lateral disturbances through through-hole jets induced by a specific structure, resulting in intense three-dimensional cross-mixing with the main airflow. These mechanisms work together to irreversibly convert macroscopic kinetic and pressure energy (total pressure) into heat energy through viscous dissipation, which is the core of achieving fundamental velocity and pressure attenuation. At the same time, the extreme mixing effect brought about by the through-hole jets greatly enhances the heat exchange between the high-temperature gas and the cooling wall and surrounding low-temperature gas, leading to a significant decrease in flame temperature.

[0056] The fourth stage: Final stabilization of asymmetric merging and momentum cancellation. At the outlet section of the vortex impedance attenuation cavity, the streams that have undergone different attenuation paths merge asymmetrically. Due to differences in velocity vectors, pressure, and temperature among the streams, intense momentum exchange and cancellation occur at the merging interface, further consuming the remaining dynamic pressure. This process makes the outlet flow velocity more uniform and gradual, and converts some kinetic energy into stable static pressure through the pressure recovery effect. Finally, the system outputs a stable airflow that has been sufficiently attenuated and reached dynamic equilibrium in terms of temperature, velocity, and pressure parameters, perfectly achieving the attenuation performance.

[0057] The visualized square flame arrestor system includes a flame arrester mounting housing 14-100 and a corrugated flame arrester 14-200 with replaceable parameters. The upper panel, lower panel, and middle partition of the flame arrester mounting housing have pre-drilled threaded holes 14-110 for fixing the flame arrester, preventing the flame arrester from loosening due to the impact of the explosion flame and affecting the experimental results. The back panel of the flame arrester mounting housing has pre-drilled threaded holes 14-111 for sensor probes, allowing sensors to penetrate deep into the flame arrester's slit channel to measure relevant parameters. The front panel of the flame arrester mounting housing has pre-drilled threaded holes 14-112 for connecting tempered glass, facilitating the installation of the visualized tempered glass window 14-113. Flanges are welded to both sides of the flame arrester mounting housing for tight connection with pipes on both sides, such as... Figure 4 As shown, where Figure 4(a) in the diagram refers to the upper panel of the flame arrester mounting housing. Figure 4 (b) is the bottom panel. Figure 4 (c) in the diagram represents the intermediate partition. Figure 4 (d) in the diagram represents the backplate.

[0058] The installation and replacement method of the flame arrester is as follows: Figure 5 , Figure 6 As shown, connecting plates 14-210 with pre-drilled threaded holes are welded to the upper and lower sides of the flame arrester. After each experiment, the tempered glass and flame arrester are removed, a new flame arrester for the next experiment is installed and secured, and finally the tempered glass is installed. The installation of the tempered glass is as follows: first, a glass gasket is installed in the glass slot of the outer viewing window glass pressure plate, and then the tempered glass is installed onto the flame arrester mounting housing to ensure the airtightness of the experimental apparatus. The visual square flame arrester system is tightly connected to the two side pipes via flanges, metal gaskets, and nuts to ensure the airtightness of the experimental apparatus at the connection points. Figure 7 As shown, the replaceable corrugated flame arresters with different parameters mainly include corrugated flame arresters with different angles, different corrugation heights, different materials, and different corrugation thicknesses. Figure 7 (a) shows corrugated flame arresters at different angles. Figure 7 (b) in the diagram represents a corrugated flame arrester with the same corrugation height. Figure 7 (c) in the image represents corrugated flame arresters made of different materials. Figure 7 In the diagram, (d) represents a corrugated flame arrester with different corrugation thicknesses.

[0059] Depending on the experimental requirements, different parameters of flame arresters can be installed. Based on the parameters of the corrugated flame arrester and the data measured in the experiment, the critical quenching temperature, critical quenching rate, critical quenching length, and critical quenching diameter of the flame can be obtained.

[0060] The formula for the critical quenching temperature is shown in formula (4): ; (4) Among them, T ext T is the critical extinction temperature. gas,min The base extinction temperature; E1, E2, and E3 are empirical coefficients, with E1 taking (5-30), E2 taking (1-20), and E3 taking (0.5-10); n1, n2, and n3 are exponential coefficients, all taking (0.5-2); δ is the corrugation thickness, h is the corrugation height, θ is the corrugation angle, and λ is the friction coefficient.

[0061] The formula for the critical quenching rate is shown in formula (5): ; (5) Among them, V ext V is the critical quenching rate. flame,0For reference flame velocity, F1, F2, and F3 are empirical coefficients, with F1 taking (1-5), F2 taking (0.5-3), and F3 taking (0.1-2); m1, m2, and m3 are exponential coefficients, all taking (0.5-2). The formula for the critical quenching length is shown in formula (6): (6) Among them, L ext For the quenching length, D h Where G1 is the hydraulic diameter, G2 and G3 are empirical coefficients, with G1 taking (1-3), G2 taking (1-4), and G3 taking (0.2-2); p1, p2 and p3 are exponential coefficients, all taking (0.5-1.5). The formula for the critical quenching diameter is shown in formula (7): (7) Where, d c d is the critical quenching diameter. g0 The base quenching diameter is given by H1, H2, and H3, which are empirical coefficients, all taking values ​​of (0.2-3); and q1, q2, and q3, which are exponential coefficients, all taking values ​​of (0.5-2).

[0062] The adjustable high-voltage ignition system consists of an adjustable high-voltage igniter 7, a program control and data acquisition system 30, and a synchronization controller 31. The adjustable high-voltage igniter 7 is installed at the left end of the first square container 1-1 and is located on the central axis of the visual detonation section pipe 2. The adjustable high-voltage igniter 7, the program control and data acquisition system 30, and the synchronization controller 31 can accurately control the discharge sequence, discharge duration, and ignition energy of the adjustable high-voltage igniter 7 to adapt to combustible gases with different minimum ignition energies and regulate the initial development state of the flame.

[0063] The high-frequency response explosion suppression system consists of a flame signal detector 16, a high-pressure fine nozzle 17, a high-precision pressure gauge 24, a high-pressure inhibitor storage tank 27, a solenoid valve 29, a program control and data acquisition system 30, and a synchronization controller 31. The flame signal detector 16 is installed on the lower wall of the end section of the protected section pipeline 3 and is connected to the program control and data acquisition system 30 and the synchronization controller 31. The high-pressure fine nozzle 17 is installed on the lower wall of the pipeline downstream of the flame signal detector 16 and extends into the interior of the visual protected section pipeline 3. The high-precision pressure gauge 24 is directly installed on the high-pressure inhibitor storage tank 27. The high-pressure inhibitor storage tank 27 is connected to the high-pressure fine nozzle 17 through the solenoid valve 29. During operation, when the flame arrestor fails, the flame signal detector 16 detects a flame signal. The synchronization controller 31 receives this signal and feeds it back to the program control and data acquisition system 30. The system then triggers the solenoid valve 29 to open, causing the inert inhibitor in the high-pressure inhibitor storage tank 27 to be atomized and sprayed out through the high-pressure fine nozzle 17, forming a covering suppression, thereby achieving rapid extinguishing of the explosion flame.

[0064] The high-precision gas distribution system consists of a flexible heating belt 18, an air compressor 19, a one-way valve 20, a high-precision circulating gas distributor 21, a high-precision vacuum pressure gauge 24, a stratified airflow distributor 22, a miniature mass flow controller 23, and a vacuum pump 28. Through the air inlet installed on the lower wall of the square container 1-1, and three air inlets on the lower walls of the front, middle, and rear sections of the visual detonation section pipeline 2, in conjunction with the stratified airflow distributor 22 and the miniature mass flow controller 23, gas can be supplied to different locations within the pipeline. One end of the high-precision circulating gas distributor 21 is connected to the visual detonation section pipeline 2 via the one-way valve 20, and the other end is connected to high-pressure test combustible gas cylinders such as hydrogen, carbon monoxide, methane, acetylene, ethylene, hydrogen sulfide, etc., and high-pressure air cylinders. The flexible heating belt 18 tightly wraps around the outer wall of the pipeline, allowing for precise control of the initial temperature of the gas under study.

[0065] a) When the research object is a uniform gas, the vacuum pump 28 is used to evacuate the inside of the explosion pipeline to a vacuum state during gas mixing. The high-precision circulating gas mixer 21 is then adjusted to achieve uniform mixing of the test combustible gas and air inside the explosion pipeline and to adjust the ratio of the test combustible gas to air, as well as the initial pressure inside the pipeline.

[0066] b) When the research object is a non-uniform gas, gas is introduced into the pipeline by a stratified airflow distributor 22 and a micro mass flow controller 23. The micro mass flow controller 23 is used to achieve precise control of the injected gas flow rate. The gas is allowed to stand for different times according to the actual situation. The gas concentration at different locations in the pipeline can be determined by a micro infrared gas concentration sensor 12. Then, the premixed gas in the pipeline is preheated by a flexible heating belt 18. Combustible gases with different parameters have different flame propagation characteristics. By adjusting the initial temperature, concentration and pressure of the tested combustible gas, the flame propagation characteristics of the tested combustible gas with different parameters can be observed and collected. The flame propagation speed is a key parameter for studying the explosion-proof and quenching characteristics of the flame arrester. By adjusting the initial concentration of the tested combustible gas, the attenuation effect of the vortex impedance attenuation cavity and the flame arrester flame arresting test are used to analyze and evaluate the attenuation effect of the vortex impedance attenuation cavity with different parameters, as well as the flame arresting performance and quenching characteristics of the flame arrester. Figure 8 The flame propagation structure of methane at different diffusion times, t DT This represents the time of free diffusion of methane, where Figure 8 (a) shows the propagation pattern of a methane flame with a free diffusion time of 20 s. Figure 8 (b) shows the propagation pattern of a methane flame with a free diffusion time of 30 s. Figure 8 (c) in the image represents the propagation pattern of a methane flame with a free diffusion time of 40 s. Figure 8(d) in the figure represents the flame propagation pattern of methane with a free diffusion time of 100 s. This shows that the flame extinguishing time decreases with the increase of the free diffusion time of methane, and the flame propagation patterns are significantly different. Figure 9 The relationship between methane free diffusion time and flame front velocity shows that the maximum flame front velocity increases with increasing free diffusion time. For example... Figure 10 As shown, the flame acceleration device 8 includes a second fixed bracket 8-2, a two-section independent spiral blade assembly coaxially nested, and a drive assembly for adjusting the angle of the spiral blades; the second fixed bracket 8-2 is located inside the visible detonation section pipe 2 and is located at one end close to the adjustable high-pressure ignition system.

[0067] The two independent helical blade assemblies are the first helical blade assembly and the second helical blade assembly, respectively. The first helical blade assembly includes a first motor 8-4, a first cylinder 8-5, a lead screw 8-6, and a first base 8-3. The first base 8-3 is fixedly connected to the second fixed bracket 8-2. The first cylinder 8-5 is rotatably connected to the first base 8-3 through a bearing. The first motor 8-4 is fixedly installed inside the first cylinder and located at one end close to the adjustable high-voltage ignition system. The output shaft of the first motor is fixedly connected to one end of the lead screw. The first blades are helically arranged on the outer wall of the first cylinder along its length.

[0068] The second helical blade assembly includes a second cylinder 8-9 and a second base 8-8. The second cylinder 8-9 is rotatably connected to the second base 8-8 via a bearing, and the second base 8-8 is located on the side closer to the first motor 8-4. A threaded through hole is provided at the center of the second base 8-8, and the second base 8-8 is sleeved on the lead screw 8-6 through the threaded through hole at its end and threadedly connected to it. A first guide rail is provided along the length direction on the inner wall of the first cylinder 8-5, and a first slider is provided on the outer wall of the second base 8-8. The first slider is slidably locked on the first guide rail. A second blade is helically arranged along the length direction on the outer wall of the second cylinder. The helical diameter of the second helical blade assembly is smaller than the inner diameter of the first cylinder. The visual detonation section pipe, the first cylinder, and the second cylinder are coaxially arranged. A limit block 8-11 is provided at the end of the lead screw, and the length of the lead screw is greater than the length of the first cylinder.

[0069] The first blade shown includes multiple first blade units 8-7, all of which are spirally and integrally arranged on the first cylinder, with gaps and discontinuities between adjacent first blade units. The second blade shown includes multiple second blade units 8-10, all of which are spirally and integrally arranged on the second cylinder, with gaps and discontinuities between adjacent second blade units.

[0070] The drive assembly for adjusting the angle of the spiral blades includes a second motor 8-12 and a third motor 8-13 disposed outside the visual detonation section pipe 2. The shafts of the second motor 8-12 and the third motor 8-13 extend into the visual detonation section pipe 2 and are sealed to the wall of the visual detonation section pipe 2. A first bevel gear 8-14 is fixedly disposed at the end of the shaft of the second motor, and a second bevel gear 8-16 is fixedly disposed at the end of the shaft of the third motor. A first bevel gear ring 8-15 is fixedly sleeved on one end of the first cylinder 8-5 near the second fixed bracket, and a second bevel gear ring 8-17 is fixedly sleeved on one end of the second cylinder 8-9 near the second fixed bracket. The first bevel gear 8-14 meshes with the first bevel gear ring 8-15. When the second cylinder is fully extended from the first cylinder, the second bevel gear 8-16 meshes with the second bevel gear ring 8-17.

[0071] The flame arrestor core temperature acquisition system consists of a patch-type K-type armored thermocouple 15, a program control and data acquisition system 30, and a synchronization controller 31. For example... Figure 11 As shown, the patch-type K-type armored thermocouple 15 is integrated and installed inside the specially designed slit channel of the flame arrester, and the flame inlet end of the slit channel is sealed to physically isolate the direct impact of the explosion flame, ensuring that the measured temperature is the temperature rise of the metal wall surface of the flame arrester caused by heat conduction. When the system is working, the patch-type K-type armored thermocouple 15 collects the transient signal of the metal wall surface temperature after the explosion flame passes through the flame arrester. This signal is fed back to the program control and data acquisition system 30 via the synchronous controller 31 for recording and storage. The obtained temperature change data is mainly used to quantitatively analyze the heat transfer effect during the quenching process of the flame arrester, thereby providing key experimental basis for evaluating the heat absorption capacity and flame arresting performance of flame arresters with different parameters.

[0072] The high-frequency pressure acquisition system consists of a first high-frequency pressure sensor 13-1, a second high-frequency pressure sensor 13-2, a third high-frequency pressure sensor 13-3, a fourth high-frequency pressure sensor 13-4, a fifth high-frequency pressure sensor 13-5, a sixth high-frequency pressure sensor 13-6, a seventh high-frequency pressure sensor 13-7, an eighth high-frequency pressure sensor 13-8, a program control and data acquisition system 30, and a synchronization controller 31.

[0073] The first high-frequency pressure sensor 13-1 is installed on the lower wall of the downstream pipe of the flame acceleration device 8; the third high-frequency pressure sensor 13-3 is installed on the lower wall of the end pipe of the visual detonation section 2; the second high-frequency pressure sensor 13-2 is installed in the middle of the first high-frequency pressure sensor 13-1 and the third high-frequency pressure sensor 13-3; the first high-frequency pressure sensor 13-1, the second high-frequency pressure sensor 13-2, and the third high-frequency pressure sensor 13-3 are used to measure the changes in pressure values ​​during the propagation of the flame of a combustible gas explosion with different parameters. After the data is saved by the program control and data acquisition system 30 and the synchronous controller 31, it can also be used as a basis for judging the flame propagation mode (deflagration or detonation). The third high-frequency pressure sensor 13-3 is also used to measure the explosion overpressure of combustible gas explosion flames with different parameters before they enter the vortex impedance attenuation chamber 5; the fourth high-frequency pressure sensor 13-4 is installed inside the inlet section of the vortex impedance attenuation chamber to measure the pressure change of the explosion flame after it just enters the vortex impedance attenuation chamber; the fifth high-frequency pressure sensor 13-5 is installed at the outlet section of the rear vortex impedance attenuation chamber to measure the pressure change of combustible gas explosion flames with different parameters after passing through the complex vortex impedance attenuation chamber; the sixth high-frequency pressure sensor 13-6 is installed on the lower wall of the front end of the protection section pipe 3; the eighth high-frequency pressure sensor 13-8 is installed on the lower wall of the upstream pipe of the flame signal detector 16; the seventh high-frequency pressure sensor 13... -7 is installed between the sixth high-frequency pressure sensor 13-6 and the eighth high-frequency pressure sensor 13-8. It is used to measure the change of flame pressure value after potential reignition and can be used to study the mechanism of reignition. It can measure the pressure value at different heights in the pipeline by changing the length of the sensor extension through the threaded hole reserved above the pipeline. The program control and data acquisition system 30 and the synchronous controller 31 detect and collect the pressure change during the propagation of the flame of the explosion of combustible gas with different parameters, the pressure drop after the flame of the explosion of combustible gas with different parameters passes through the eddy wave impedance attenuation cavity with different parameters and the flame arrester with different parameters, so as to evaluate the attenuation performance of the eddy wave impedance attenuation cavity with different parameters and the flame arrester with different parameters.

[0074] The high-frequency temperature acquisition system consists of a high-speed infrared thermal imager 26, a first high-temperature thermocouple 10-1, a second high-temperature thermocouple 10-2, a third high-temperature thermocouple 10-3, a fourth high-temperature thermocouple 10-4, a fifth high-temperature thermocouple 10-5, a sixth high-temperature thermocouple 10-6, a seventh high-temperature thermocouple 10-7, an eighth high-temperature thermocouple 10-8, a first K-type armored thermocouple 14-1, a second K-type armored thermocouple 14-2, a program control and data acquisition system 30, and a synchronization controller 31. The high-speed infrared thermal imager can be viewed macroscopically through a visual tempered glass window 4-2. The flame temperature of explosion flames with different parameters is measured in the visualized ignition section pipe 2, the visualized square flame arrester 6, and the visualized protection section pipe 3. The first high-temperature thermocouple 10-1, the second high-temperature thermocouple 10-2, and the third high-temperature thermocouple 10-3 are respectively installed at the same radial position on the upper and lower sides of the pipe along with the first high-frequency pressure sensor 13-1, the second high-frequency pressure sensor 13-2, and the third high-frequency pressure sensor 13-3. This is used to measure the temperature changes during the propagation of explosion flames with different parameters, and can also serve as a basis for determining the flame propagation pattern, such as deflagration or detonation. Thermocouple 10-3 is also used to measure the temperature of flammable gas explosion flames with different parameters before entering the vortex impedance attenuation cavity 5. The fourth high-temperature thermocouple 10-4 is installed inside the front section of the vortex impedance attenuation cavity 5 to measure the temperature change of the explosion flame immediately after entering the vortex impedance attenuation cavity. The fifth high-temperature thermocouple 10-5 is installed in the rear section of the vortex impedance attenuation cavity 5 to measure the temperature change of explosion flames with different parameters after passing through the complex attenuation effect of the vortex impedance attenuation cavity. The sixth high-temperature thermocouple 10-6, the seventh high-temperature thermocouple 10-7, and the eighth high-temperature thermocouple... Thermocouple 10-8 is located at the same radial position on the upper and lower sides of the sixth high-frequency pressure sensor 13-6, the seventh high-frequency pressure sensor 13-7, and the eighth high-frequency pressure sensor 13-8, respectively. It is used to determine the temperature change of the flame after potential reignition and can be used to study the mechanism of reignition. It can also measure the temperature value of the combustible gas explosion flame at different heights in the pipeline by changing the length of the sensor extension through the threaded hole reserved above the pipeline, so as to evaluate the temperature attenuation effect of the eddy wave impedance attenuation cavity with different parameters and the flame arresting performance of the flame arrester with different parameters.

[0075] like Figure 12As shown, the first K-type armored thermocouple 14-1 and the second K-type armored thermocouple 14-2 are respectively installed on the flame arrester back plate 14-100-4. The probe is inserted into the slit channel through the reserved threaded hole to measure the temperature change during the quenching process and obtain the critical quenching temperature of the flame. The program control and data acquisition system 30 and the synchronous controller 31 detect and collect the temperature change during the propagation of the combustible gas explosion flame with different parameters, the temperature change after the combustible gas explosion flame with different parameters passes through the eddy wave impedance attenuation cavity with different parameters, and the temperature change during the quenching process of the combustible gas explosion flame with different parameters in the flame arrester with different parameters.

[0076] The flame ion concentration acquisition system consists of a first flame ion probe 11-1, a second flame ion probe 11-2, a third flame ion probe 11-3, a fourth flame ion probe 11-4, a fifth flame ion probe 11-5, a sixth flame ion probe 11-6, a seventh flame ion probe 11-7, an eighth flame ion probe 11-8, a program control and data acquisition system 30, and a synchronization controller 31. The first flame ion probe 11-1, the second flame ion probe 11-2, and the third flame ion probe 11-3 are respectively installed on the upper wall of the downstream pipe of the first high-temperature thermocouple 10-1, the second high-temperature thermocouple 10-2, and the third high-temperature thermocouple 10-3. They are used to measure the changes in flame ion concentration during the propagation of combustible gas explosion flames with different parameters, and can also be used as a basis for judging the propagation mode of combustible gas explosion flames with different parameters, such as deflagration or detonation. The fourth flame ionization probe 11-4 and the fifth flame ionization probe 11-5 are respectively installed on the rear plate of the flame arrester. The probes are inserted into the slit channel through pre-drilled threaded holes to observe the quenching characteristics of flammable gas explosion flames with different parameters, obtain their critical quenching length, and measure the wall effect in the quenching principle. The sixth flame ionization probe 11-6, the seventh flame ionization probe 11-7, and the eighth flame ionization probe 11-8 are respectively installed on the upper wall of the downstream pipes of the sixth high-temperature thermocouple 10-6, the seventh high-temperature thermocouple 10-7, and the eighth high-temperature thermocouple 10-8; they are used to determine potential reignition phenomena and the flame size after reignition. The changes in flame ion concentration can be used to study the mechanism of reignition; and by changing the length of the sensor insertion through the threaded hole reserved above the pipe, the changes in flame ion concentration of combustible gas explosion flames with different parameters at different height positions in the pipe can be measured to evaluate the flame arresting performance of flame arresters with different parameters; the changes in flame ion concentration during the propagation of combustible gas explosion flames with different parameters and the changes in flame ion concentration during the quenching process inside the slit channel of flame arresters with different parameters can be detected and collected by the program control and data acquisition system 30 and the synchronous controller 31.

[0077] The gas concentration monitoring system comprises a first miniature infrared gas concentration sensor 12-1, a second miniature infrared gas concentration sensor 12-2, a third miniature infrared gas concentration sensor 12-3, a fourth miniature infrared gas concentration sensor 12-4, a fifth miniature infrared gas concentration sensor 12-5, a sixth miniature infrared gas concentration sensor 12-6, a seventh miniature infrared gas concentration sensor 12-7, a program control and data acquisition system 30, and a synchronization controller 31. The first miniature infrared gas concentration sensor 12-1 is installed on the lower wall of the pipe at the inlet of the detonation section pipe 2 to measure the gas concentration at the front end of the pipe. The second miniature infrared gas concentration sensor 12-2, the third miniature infrared gas concentration sensor 12-3, and the fourth miniature infrared gas concentration sensor 12-4 are respectively installed on the first high-frequency pressure sensor 13-1 and the second high-frequency pressure sensor 13-2. The third high-frequency pressure sensor 13-3 is installed on the lower wall of the downstream pipe to measure the changes in the concentration of combustible gas at different locations inside the pipe. The fifth, sixth, and seventh miniature infrared gas concentration sensors 12-5, 12-6, and 12-7 are respectively installed on the lower wall of the downstream pipe of the fifth, sixth, and seventh high-frequency pressure sensors 13-5, 13-6, and 13-7. These sensors are used to measure the concentration of combustible gas in potential reignition phenomena and to study the mechanism of reignition. By changing the length of the sensor insertion through the threaded hole reserved above the pipe, the gas concentration at different heights inside the pipe can be measured, which can be used to determine the degree of diffusion of non-uniform combustible gas. The program control and data acquisition system 30 and the synchronous controller 31 detect and collect the concentration of combustible gas at different locations inside the pipe.

[0078] The flame pattern acquisition system consists of a high-speed camera 25, a program control and data acquisition system 30, and a synchronization controller 31. The high-speed camera 25 can accurately capture the dynamic propagation process of the flame from the explosion of combustible gas with different parameters in the visual tempered glass window 4-2 installed on the visual detonation section pipe 2, and the dynamic quenching process of the flame in the visual tempered glass window on the visual square flame arrester 6, as well as its critical quenching length and critical quenching speed; and accurately capture the development process of potential reignition phenomena in the protection section pipe 3.

[0079] Example 2: Experimental method for testing the explosion-proof performance of the eddy current flame arrestor system based on the above device, specifically including the following steps: Step S1. Install and debug the test apparatus to ensure that: the visual square explosion pipeline, the vortex impedance attenuation chamber system, the visual square flame arrestor system, the adjustable high-pressure ignition system, the high-frequency response explosion suppression system, the high-precision gas distribution system, the flame acceleration device, the flame arrestor core temperature acquisition system, the high-frequency pressure acquisition system, the high-frequency temperature acquisition system, the flame ion concentration acquisition system, the gas concentration monitoring system, the flame morphology acquisition system, the program control and data acquisition system 30, and the synchronous controller 31 are all in good condition. After installing the housing of the visual square flame arrester, install the corrugated flame arresters with different parameters required for the test into the visual square flame arrester to form the visual square flame arrester 6. Then, connect it tightly to the vortex impedance attenuation chamber 5, the visual detonation section pipeline 2, and the visual protection section pipeline 3 by means of flange connection.

[0080] Step S2. Vacuuming the pipeline: When conducting tests on the propagation characteristics of combustible gases with different parameters, the eddy wave impedance attenuation chamber with different parameters, and the flame arrester performance with different parameters in the sealed explosion pipeline, ensure that the pipeline has good airtightness, open the valve and use vacuum pump 28 to evacuate the explosion pipeline.

[0081] Step S3. Premixed Gas Preparation and Preheating: Premixed combustible gases with different parameters are prepared using a high-precision gas mixing system and a gas concentration monitoring system, and then introduced into the explosion pipeline. After the premixed gas is introduced, the pressure inside the explosion pipeline is at atmospheric pressure, and the inlet valve of the explosion pipeline is closed. a) When the research object is a homogeneous gas, the gas is allowed to stand for about 30 seconds to reach a stable and static state. Then, the mixed gas in the pipeline is heated using a flexible heating belt 18 tightly wrapped around the outer wall of the pipeline, achieving precise control of the initial concentration, temperature, and pressure of different combustible gases. b) When the research object is a non-homogeneous gas, the standing time needs to be adjusted according to the type of gas. A micro mass flow controller 23 is used to achieve precise control of the injected gas flow rate.

[0082] Step S4. The adjustable high-voltage igniter 7 is controlled by the synchronous controller 31 to discharge and ignite the premixed gas. The explosion flame propagation speed is effectively changed by the flame acceleration device 8. The flame propagation speed is changed by changing the length and blade angle of the flame acceleration device 8, so as to achieve the regulation of the flame propagation speed. At the same time, the flame propagation speed can also be changed by changing the ignition energy and the premixed gas concentration.

[0083] Step S5. By coordinating the synchronous controller 31 with flame ion probes 11-1, 11-2, and 11-3, the changes in ion concentration during the propagation of combustible gas explosion flames with different parameters are measured. This can be used to determine the shape and speed of flame propagation. At the same time, the flame propagation speed can be determined by the high-speed camera 25. By monitoring the concentration of flame free radical ions in the slit channel of the corrugated flame arrester with different parameters using flame ion probes 11-4 and 11-5, the quenching distance of the explosion flame can be determined. At the same time, the wall effect in the quenching effect can be measured by the change in flame ion concentration. Furthermore, the changes in flame ion concentration in potential reignition phenomena can be measured by flame ion probes 11-6, 11-7, and 11-8.

[0084] Step S6. By coordinating the synchronous controller 31 with high-temperature thermocouples 10-1, 10-2, and 10-3, the temperature during the propagation of the flame of a combustible gas explosion with different parameters can be measured, and the temperature changes during the propagation of the flame of a combustible gas explosion with different parameters can be clearly analyzed. At the same time, the high-speed infrared thermal imager 26 is used to obtain the macroscopic flame temperature in the visualized tempered glass window on the visualized detonation section pipe 2 of the combustible gas explosion flame with different parameters, and the temperature changes during the propagation of the flame of a combustible gas explosion with different parameters can be clearly analyzed. High-temperature thermocouples 10-4 and 10-5 are used to obtain the flame temperature changes before and after the flame passes through the eddy wave impedance attenuation cavity. At the same time, the sixth high-temperature thermocouple 10-6, the seventh high-temperature thermocouple 10-7, and the eighth high-temperature thermocouple 10-8 can be used to determine the flame temperature changes in potential reignition phenomena.

[0085] Step S7. By coordinating the synchronous controller 31 with the K-type armored thermocouples 14-1 and 14-2 to measure the internal temperature of corrugated flame arresters with different parameters, the temperature changes during the quenching process of flammable gas explosion flames with different parameters can be further analyzed.

[0086] Step S8. By coordinating the synchronous controller 31 with the patch-type K-type armored thermocouples 15 on the wall of the flame arrester with different parameters, the temperature change of the corrugated flame arrester with different parameters can be accurately monitored, and the heat absorption effect of the corrugated flame arrester with different parameters on the explosion flame of the combustible gas with different parameters can be obtained, so as to measure the heat transfer effect in the quenching effect.

[0087] Step S9. By using a visual tempered glass window and combining it with a high-speed camera 25 through the synchronous controller 31, the evolution process of the explosion flame morphology, the quenching process, the critical quenching length, the critical quenching speed, and the potential reignition phenomenon can be effectively obtained. This allows for a more systematic and comprehensive analysis of the propagation characteristics of flammable gas explosion flames with different parameters, the flame-arresting performance of flame arresters with different parameters, and the mechanism of potential reignition phenomena.

[0088] Step S10. The high-frequency pressure sensors 13-1, 13-2, and 13-3, controlled by the synchronous controller 31, can clearly analyze the pressure changes during the propagation of the combustible gas explosion flame with different parameters; the high-frequency pressure sensors 13-4 and 13-5 are used to obtain the pressure changes of the explosion flame before and after passing through the eddy wave impedance attenuation chamber; at the same time, the pressure changes in potential reignition phenomena can be measured by the sixth high-frequency pressure sensor 13-6, the seventh high-frequency pressure sensor 13-7, and the eighth high-frequency pressure sensor 13-8.

[0089] Step S11. The first miniature infrared gas concentration sensor 12-1, the second miniature infrared gas concentration sensor 12-2, the third miniature infrared gas concentration sensor 12-3, the fourth miniature infrared gas concentration sensor 12-4, the fifth miniature infrared gas concentration sensor 12-5, the sixth miniature infrared gas concentration sensor 12-6, and the seventh miniature infrared gas concentration sensor 12-7, which are controlled in coordination by the synchronous controller 31, can detect the gas concentration at different locations and heights in the pipeline in real time.

[0090] Step S12. The high-frequency response explosion suppression system, including the flame signal detector 16, the high-pressure inhibitor storage tank 27, and the solenoid valve 29, is coordinated by the synchronous controller 31. ① If the flame signal detector 16 receives a flame signal, it is determined that the flame arrestor has failed, and a signal is immediately fed back to the program control and data acquisition system 30, which issues a command to promptly open the solenoid valve 29 of the high-pressure inhibitor storage tank 27. Inert inhibitors are sprayed through the high-pressure fine nozzle 17 to effectively suppress the explosion flame. ② If the flame signal detector 16 does not detect a flame signal, it is determined that the flame arrestor has succeeded. The high-frequency response explosion suppression system ensures the safety of the experimental device.

[0091] Step S13. After the experiment, once the exhaust gas in the pipeline has returned to room temperature, use air compressor 19 to discharge the exhaust gas from the pipeline. This round of testing is now complete. Repeat steps S1-S13 to begin the next round of testing.

Claims

1. An experimental apparatus for testing the explosion-proof performance of a vortex current flame arrestor system, characterized in that, include: Visualized square explosion pipe, vortex impedance attenuation cavity system, visualized square flame arrestor system, adjustable high-pressure ignition system, high-frequency response explosion suppression system, high-precision gas distribution system, flame acceleration device, multi-dimensional parameter acquisition system, program control and data acquisition system (30) and synchronous controller (31). The program control and data acquisition system (30) establishes signal connections with the adjustable high-pressure ignition system, high-frequency response explosion suppression system, high-precision gas distribution system, flame acceleration device and multi-dimensional parameter acquisition system through the synchronous controller (31), so as to realize the time-series coordinated control of each system and the synchronous acquisition, storage and analysis of test data; The multi-dimensional parameter acquisition system integrates functions such as flame arrestor core temperature acquisition, high-frequency pressure acquisition, high-frequency temperature acquisition, flame ion concentration acquisition, gas concentration monitoring, and flame morphology acquisition.

2. The experimental apparatus according to claim 1, characterized in that, The eddy wave impedance attenuation cavity system is a dual-axis symmetrical cavity structure, consisting of two coaxially arranged inner and outer circular pipes with expanded spherical surfaces, referred to as the outer pipe and the inner pipe, with a gap between the outer pipe and the inner pipe. The outer pipeline, along its length, includes, in sequence, a first horizontal section, a first corner section, a first bend section, a first corner section, and a first horizontal section, with the radius of the first bend section being greater than the radius of the first horizontal section; the inner pipeline, along its length, includes, in sequence, a diversion section, a second horizontal section, a second corner section, a second bend section, a second corner section, a second horizontal section, and a diversion section, with the radius of the second bend section being greater than the radius of the second horizontal section; The inner pipe is nested in the outer pipe and is fixedly connected to the outer pipe by a rigid fixing bracket. The pipe wall of the first curved section near the visual square fire arresting system has uniform through holes. Both ends of the outer pipe are welded with flanges, which are respectively connected to the visual detonation section pipe (2) and the visual square fire arrestor system; thermocouples and pressure sensors are installed at both ends of the outer pipe near the flanges.

3. The experimental apparatus according to claim 2, characterized in that, The temperature attenuation rate of the eddy wave impedance attenuation cavity system for the explosion flame is shown in formula (1): ; (1) Wherein, ∆T / T1 is the temperature decay rate, ∆T=T2-T1, T1 is the temperature value measured by the thermocouple at the front end of the vortex impedance attenuation cavity, and T2 is the temperature value measured by the thermocouple at the rear end of the vortex impedance attenuation cavity; k1, k2, k3, k4 are weighting coefficients, all of which are (0.01-0.5); L1 is the length of the first horizontal section, D1 is the diameter of the outer pipe inlet section, L2 is the length of the second horizontal section, D2 is the diameter of the inner pipe inlet section, R1 is the radius of curvature of the first bending section, R2 is the radius of curvature of the second bending section, φ is the porosity of the through hole on the first bending section, d is the diameter of the through hole, and X is the expansion ratio of the pipe; the front end is the end close to the visual detonation section pipe (2), and the rear end is the end close to the visual square fire arrestor system; The pressure attenuation rate of the vortex impedance attenuation cavity system for the explosion flame is shown in formula (2): ； （2） Wherein, ∆P / P1 is the pressure attenuation rate, ∆P=P2-P1, P1 is the pressure value measured by the pressure sensor at the front end of the eddy wave impedance attenuation cavity, and P2 is the pressure value measured by the pressure sensor at the rear end of the eddy wave impedance attenuation cavity; C1, C2, C3, and C4 are weighting coefficients, all ranging from 0.01 to 0.3; X is the expansion ratio of the pipe; α1 is the angle between the line connecting the beginning and end of the first corner segment and the horizontal direction; α2 is the angle between the line connecting the beginning and end of the second corner segment and the horizontal direction; S1 is the horizontal length of the first corner segment; S2 is the horizontal length of the second corner segment; and ε is the relative roughness of the pipe wall. The velocity attenuation rate of the vortex impedance attenuation cavity system for the explosion flame is shown in formula (3): (3) Where ∆V / V1 is the flame propagation velocity attenuation rate, ∆V=V2-V1, V1 is the flame propagation velocity before entering the vortex impedance attenuation cavity, and V2 is the flame propagation velocity after passing through the vortex impedance attenuation cavity; M1, M2, M3, and M4 are weighting coefficients, all of which are taken as (0.05-0.5).

4. The experimental apparatus according to claim 1, characterized in that, The visualized square flame arrestor system includes a flame arrestor mounting housing and a replaceable corrugated flame arrestor. The flame arrester mounting housing has a flame arrester fixing structure on the upper panel, lower panel and middle partition, a sensor probe mounting hole on the back panel, a visual window connection structure on the front, and flanges welded at both ends. The corrugated flame arrester is detachably installed in the flame arrester mounting housing through a fixed structure, and the flame arrester mounting housing is provided with flanges at both ends. Corrugated flame arresters with different parameters are installed according to experimental needs. These parameters include the corrugation angle, corrugation height, material, and corrugation thickness of the corrugated flame arrester.

5. The experimental apparatus according to claim 4, characterized in that, Based on the parameters of the corrugated flame arrester and the experimentally measured data, the critical quenching temperature, critical quenching rate, critical quenching length, and critical quenching diameter of the flame can be obtained. The formula for the critical quenching temperature is shown in formula (4): ； （4） Among them, T ext T is the critical extinction temperature. gas,min The base extinction temperature; E1, E2, and E3 are empirical coefficients, with E1 taking values ​​of (5-30), E2 taking values ​​of (1-20), and E3 taking values ​​of (0.5-10); n1, n2, and n3 are exponential coefficients, all taking values ​​of (0.5-2); δ is the corrugation thickness, and h is the corrugation height. λ is the corrugation angle, and λ is the friction coefficient. The formula for the critical quenching rate is shown in formula (5): ； （5） Among them, V ext V is the critical quenching rate. flame,0 For reference flame velocity, F1, F2, and F3 are empirical coefficients, with F1 taking (1-5), F2 taking (0.5-3), and F3 taking (0.1-2); m1, m2, and m3 are exponential coefficients, all taking (0.5-2). The formula for the critical quenching length is shown in formula (6): ； （6） Among them, L ext For the quenching length, D h Where G1 is the hydraulic diameter, G2 and G3 are empirical coefficients, with G1 taking (1-3), G2 taking (1-4), and G3 taking (0.2-2); p1, p2 and p3 are exponential coefficients, all taking (0.5-1.5). The formula for the critical quenching diameter is shown in formula (7): ； （7） Where, d c d is the critical quenching diameter. g0 The base quenching diameter is given by H1, H2, and H3, which are empirical coefficients, all taking values ​​of (0.2-3); and q1, q2, and q3, which are exponential coefficients, all taking values ​​of (0.5-2).

6. The experimental apparatus according to claim 1, characterized in that, The flame acceleration device includes a second fixed bracket, a two-section independent helical blade assembly coaxially nested, and a drive assembly for adjusting the angle of the helical blades. The second fixed bracket is located inside the visible detonation section pipe (2) and is close to one end of the adjustable high-pressure ignition system; The two independent helical blade assemblies are the first helical blade assembly and the second helical blade assembly, respectively; wherein, the first helical blade assembly includes a first motor, a first cylinder, a lead screw and a first base; the second fixed bracket is fixedly connected to the first base, the first cylinder is rotatably connected to the first base through a bearing, the first motor is fixedly installed in the first cylinder, the output shaft of the first motor is fixedly connected to one end of the lead screw, and the first blade is helically arranged on the outer wall of the first cylinder along its length direction; The second helical blade assembly includes a second cylinder and a second base. The second cylinder is rotatably connected to the second base via a bearing, and the second base is located on the side closer to the first motor. A threaded through hole is provided at the center of the second base, and the second base is sleeved on the lead screw through the threaded through hole at its end and threadedly connected to it. A first guide rail is provided along the length direction on the inner wall of the first cylinder, and a first slider is provided on the outer wall of the second base. The first slider is slidably locked on the first guide rail. A second blade is helically arranged along the length direction on the outer wall of the second cylinder. The helical diameter of the second helical blade assembly is smaller than the inner diameter of the first cylinder. The visualized detonation section pipe, the first cylinder, and the second cylinder are coaxially arranged. A limit block is provided at the end of the lead screw, and the length of the lead screw is greater than the length of the first cylinder. The first blade shown includes multiple first blade units, all of which are spirally and integrally arranged on the first cylinder, with gaps and discontinuities between adjacent first blade units; The second blade shown includes multiple second blade units, all of which are spirally and integrally arranged on the second cylinder, with gaps and discontinuities between adjacent second blade units; The drive assembly for adjusting the angle of the spiral blades includes a second motor and a third motor disposed outside the visual detonation section pipe (2). The shafts of the second motor and the third motor extend into the visual detonation section pipe (2) and are sealed to the wall of the visual detonation section pipe (2). A first bevel gear is fixedly disposed at the end of the shaft of the second motor, and a second bevel gear is fixedly disposed at the end of the shaft of the third motor. A first bevel gear ring is fixedly fitted on one end of the first cylinder near the fixed support, and a second bevel gear ring is fixedly fitted on one end of the second cylinder near the fixed support. The first bevel gear meshes with the first bevel gear ring. When the second cylinder is fully extended from the first cylinder, the second bevel gear meshes with the second bevel gear ring.

7. The experimental apparatus according to any one of claims 1-6, characterized in that, The visualized square explosion conduit includes a visualized detonation section conduit (2) and a visualized protection section conduit (3) arranged along the same central axis. One end of the visual detonation section pipe (2) is sealed and connected to the first square container (1-1) with a visual window through a flange, and is in communication with it; the other end of the visual detonation section pipe (2) is sealed and connected to one end of the vortex impedance attenuation cavity system through a flange, and is in communication with the attenuation cavity (5) of the vortex impedance attenuation cavity system. One end of the visual protection section pipe (3) is sealed and connected to the second square container (1-2) with a visual window through a flange, and is in communication with it; the other end of the visual protection section pipe (3) is sealed and connected to one end of the visual square fire arresting system through a flange; the other end of the visual square fire arresting system is sealed and connected to the other end of the eddy wave impedance attenuation cavity system through a flange, and is in communication with the attenuation cavity (5) of the eddy wave impedance attenuation cavity system. The walls of the visual detonation section pipe (2) and the visual protection section pipe (3) are both fitted with high-intensity visual windows along their length for use in conjunction with a multi-dimensional parameter acquisition system to observe the flame propagation, quenching and potential reignition processes.

8. The experimental apparatus according to claim 4, characterized in that, The adjustable high-voltage ignition system consists of an adjustable high-voltage igniter (7), a program control and data acquisition system (30), and a synchronization controller (31). The adjustable high-voltage igniter (7) is coaxially installed in the first square container (1-1) at one end away from the visual detonation section pipe (2), and the ignition electrode is located on the central axis of the visual detonation section pipe (2). Through the program control and data acquisition system (30) and the synchronization controller (31), the discharge sequence, discharge duration, and ignition energy of the adjustable high-voltage igniter (7) can be adjusted to adapt to combustible gases with different minimum ignition energies and to regulate the initial development state of the flame. The high-frequency response explosion suppression system consists of a flame signal detector (16), a high-pressure fine nozzle (17), a high-pressure inhibitor storage tank (27), a solenoid valve (29), a program control and data acquisition system (30), and a synchronization controller (31). The flame signal detector (16) is installed at the end of the visual protection section pipeline (3) and is connected to the program control and data acquisition system (30) and the synchronization controller (31). The high-pressure fine nozzle (17) is installed in the pipeline downstream of the flame signal detector (16) and is connected to the high-pressure inhibitor storage tank (27) through the solenoid valve (29). When the flame arrestor fails, the trigger signal of the flame signal detector (16) is fed back to the program control and data acquisition system (30) through the synchronization controller (31), which then controls the solenoid valve (29) to open, and the inert inhibitor is atomized and sprayed out through the high-pressure fine nozzle (17) to extinguish the flame. The high-precision gas distribution system consists of a flexible heating belt (18), a high-precision circulating gas distributor (21), a stratified airflow distributor (22), a micro mass flow controller (23), and a vacuum pump (28). The first square container (1-1) and the visual detonation section pipeline (2) are equipped with multiple sets of air inlets, which work together with the stratified airflow distributor (22) and the micro mass flow controller (23) to achieve multi-position gas delivery. The high-precision circulating gas distributor (21) is connected to the combustible gas source, the air source, and the visual detonation section pipeline (2) respectively. The flexible heating belt (18) is wrapped around the outer wall of the pipeline to regulate the initial gas temperature. The vacuum pump (28) and the high-precision circulating gas distributor (21) can be used to prepare uniform premixed gas, and the stratified airflow distributor (22) and the micro mass flow controller (23) can be used together to prepare non-uniform premixed gas.

9. The experimental apparatus according to claim 8, characterized in that, The multi-dimensional parameter acquisition system includes: The flame arrestor core temperature acquisition unit is used to collect the temperature of the flame arrestor core, and its sensor is integrated inside the slit channel of the flame arrestor. The high-frequency pressure acquisition unit used to collect pressure data has its sensors installed in the visual detonation section pipeline (2), the eddy wave impedance attenuation cavity (5), and the visual protection section pipeline (3). The high-frequency temperature acquisition unit, used for collecting temperature data, has its sensors arranged in a corresponding manner with the high-frequency pressure acquisition unit sensors, and works in conjunction with a high-speed infrared thermal imager to obtain the macroscopic temperature of the flame. A flame ion concentration acquisition unit is used to collect flame ion concentration, and its probes are deployed in pipes and flame arrester slit channels. A gas concentration monitoring unit is used to monitor gas concentration, and its sensors are installed at different locations in the pipeline. A flame pattern acquisition unit for capturing flame patterns, featuring a high-speed camera and a visual window optical adapter.

10. A test method for evaluating the explosion-proof performance of a vortex current flame arrestor system based on the device described in any one of claims 1 to 9, characterized in that, Includes the following steps: Step S1. Device assembly and commissioning: Select the corrugated flame arrester with the target parameters, assemble the visual square flame arresting system, complete the sealed connection of the entire explosion pipeline link, and commission the function and airtightness of each system component. Step S2. Vacuuming the pipeline: The exploded pipeline and related systems are evacuated to a preset vacuum state using a vacuum pump (28); Step S3. Premixed gas preparation and preheating: Prepare uniform or non-uniform premixed gas through a high-precision gas mixing system, and control the initial temperature and pressure of the gas. Step S4. Ignition and data acquisition: The adjustable high-voltage igniter (7) is triggered by the synchronous controller (31) to ignite, and the multi-dimensional parameter acquisition system is started at the same time to collect parameter data of flame propagation, attenuation, quenching and potential reignition process. Step S5. Safety protection and exhaust gas treatment: After ignition, the flame arrestor status is monitored by the flame signal detector (16). When the flame arrestor fails, the high-frequency response explosion suppression system is triggered. After the experiment, the exhaust gas is cooled to room temperature, the exhaust gas is discharged and the device is reset.

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