Shock wave induced deposition dust secondary explosion flame flow field testing device and method

Abstract

The invention provides a shock wave induced deposition dust secondary explosion flame flow field testing device and method.The device comprises a gas explosion section, a dust laying section, an ignition mechanism, a shock wave generating mechanism and a data collecting and processing system, the gas explosion section and the dust laying section are connected in a communicated mode, and the data collecting and processing system is specifically a computer with preset processing software; and the data acquisition module is used for acquiring image and pressure data in the testing process of the gas explosion section and the dust laying section, and analyzing and processing. The device can be used for various experiments such as combustible gas explosion, combustible dust explosion, shock wave winding dust secondary explosion, explosion suppression, explosion venting and the like in a pipeline; the influence rules of factors such as dust concentration, dust stacking position and state, fuel gas equivalence ratio, shock wave pressure, pipeline length and type, diaphragm shape and the like on particle winding dynamics, explosion pressure and macroscopic flame characteristics in the dust secondary explosion process are analyzed; the dust raising-ignition-deflagration dynamic evolution process and the coupling mechanism of the dust particles under shock wave induction are explored.

Description

Technical Field

[0001] This invention belongs to the field of dust explosion testing technology, specifically relating to a shock wave-induced deposition dust secondary explosion flame flow field testing device and method. Background Technology

[0002] In industrial sectors such as coal mining, grain processing, and chemical production, the initial explosion triggered by a mixture of flammable gases and air encountering an ignition source poses a significant safety hazard. When the high-temperature, high-pressure shockwave generated by such an explosion propagates within a confined space, it violently stirs up flammable dust deposited on equipment walls, floors, or corners, forming a high-concentration dust cloud. When the stirred-up dust reaches the explosive limit concentration and encounters residual open flames from the initial explosion or a high-temperature environment, it will trigger a more destructive secondary dust explosion.

[0003] Existing secondary explosion experimental devices all employ multiple horizontal pipe sections connected together. Many of these pipes are fully enclosed rigid structures with a small glass window in the middle, making it impossible to clearly observe the shock wave-induced dust particle transport, thus affecting flow field dynamics analysis. Furthermore, the thin membrane separating the gas and dust ends within the pipes is prone to unexpected rupture, and the pressure at the gas end cannot be controlled. The fixed pipe layout cannot accommodate different dust accumulation patterns. These limitations hinder secondary explosion research and fail to meet its research requirements.

[0004] Therefore, developing an easy-to-operate, visual, automated shock wave-induced deposition dust secondary explosion flame flow field testing device to reproduce the complex explosion disaster chain in real industry and reveal the "shock wave-flame-turbulence" coupling mechanism is a technical problem that urgently needs to be solved by those skilled in the art.

[0005] Based on this, a test device and method for testing the flow field of secondary explosion flames caused by shock wave-induced deposition of dust are proposed. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a shock wave-induced deposition dust secondary explosion flame flow field testing device and method to address the shortcomings of the prior art, so as to solve the problems mentioned in the background art.

[0007] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: In a first aspect, a shock wave-induced deposition dust secondary explosion flame flow field testing device includes a gas explosion section and a dust laying section that are interconnected. An ignition mechanism is installed at the front end of the gas explosion section; A shock wave generating mechanism is installed in the gas explosion section near the ignition mechanism; The data acquisition and processing system, specifically a computer with pre-set processing software, is used to acquire and analyze image and pressure data during the testing process of the gas explosion section and the dust laying section. An additional pipe section is vertically fixed and connected to the end of the dust laying section. It is used to assemble with the gas explosion section and the dust laying section into a bend or T-shaped pipe for experiments under different working conditions.

[0008] As a further explanation of the present invention, an electromagnetic valve is provided at the connection between the gas explosion section and the dust laying section, and the electromagnetic valve is connected to the data acquisition and processing system via a signal connection.

[0009] The solenoid valve has a detachable and replaceable square flange with a through hole in the middle, with a hole diameter of Φ60mm. The flange has a standardized groove embedded in it, which can be used to install customized film molds of different shapes. The film is stuck in the middle of the mold, which supports the study of the impact of explosion vents of different shapes on deposited dust.

[0010] As a further explanation of the present invention, the gas explosion section and the dust laying section are both square pipelines; The bottom surface of the square pipe is made of rigid material, and four transparent glass windows are equally spaced on the other three surfaces. The inner diameter of the transparent glass window is 11cm. A laser generator is connected to the top of the transparent glass window through a light guide arm. The laser generator vertically shoots the laser into the transparent glass window. A high-speed camera connected to the data acquisition and processing system is set on the front of the transparent glass window. The square pipe is also pre-set with sensor connection holes, through which data acquisition sensors are installed, and the sensors are also connected to the data acquisition and processing system.

[0011] As a further explanation of the present invention, the wall thickness of the square pipe is 15mm and the pressure bearing capacity is greater than 20MPa; the gas explosion section has a flame acceleration section of 0.5m and a shock wave propagation section of 1.5m, and the total length of the gas explosion section and the dust laying section is 5m.

[0012] As a further explanation of the present invention, a programmable electromagnetic vibration plate with a length of 20cm and a width of 12cm is embedded at the bottom of the dust laying section. During testing, the frequency can be adjusted to make the dust generate different accumulation patterns.

[0013] As a further explanation of the present invention, the stacking morphology is specifically a uniform thin layer, a ring-shaped stacking, a mound-shaped stacking, a layered structure, or a corner aggregation morphology.

[0014] As a further explanation of the present invention, the ignition mechanism consists of a vacuum pump, a gas cylinder, a ball valve and an ignition electrode connected in sequence. The ignition electrode is specifically composed of two copper welding rods with a diameter of 5mm arranged opposite each other, and the distance between the two copper welding rods is no more than 6mm.

[0015] As a further explanation of the present invention, the shock wave generating mechanism is specifically a flame acceleration ring or a shock wave generator; When the flame acceleration ring is used in conjunction with the solenoid valve, the shock wave pressure output by the solenoid valve is controlled by the solenoid valve and used to study the interaction between combustible gas and deposited dust. When the shock wave generator is used in conjunction with a thin film embedded in flanges of different shapes, the shock wave generator controls the output shock wave pressure to study the interaction between shock waves and deposited dust. Solenoid valves cannot control the shape of the explosion vent, but flanges can. The flame acceleration ring and the shock wave generator share a common base for easy disassembly. The flame acceleration ring has an inner diameter of 100mm, an obstacle blocking ratio of 0.6, and a combustible gas cylinder is connected to the outside of the flame acceleration ring. The shock wave generator is connected to an air cylinder.

[0016] As a further explanation of the present invention, the additional pipe section is connected to the dust laying section through a four-way pipe, and the additional pipe section is also provided with a transparent glass window and a pressure relief valve, and a programmable electromagnetic vibration plate is provided on the bottom surface of the additional pipe section.

[0017] Secondly, a testing method for a shock wave-induced deposition dust secondary explosion flame flow field testing device includes the following steps: S1. Assemble the gas explosion section, dust laying section, additional pipeline section, ignition mechanism, shock wave generation mechanism and data acquisition and processing system according to the experimental plan, and perform corresponding debugging and settings. S2. Select the location for dust laying in the dust laying section, place a certain amount of dust in the dust laying section, use a vacuum pump to evacuate the square pipeline to a low vacuum of less than 1 kPa, observe and confirm that the seal is good, then open the vent valve, and close the vent valve after the pressure in the square pipeline returns to normal. S3. Open the preset Insight4G software in the data acquisition and processing system, adjust the parameters of the laser generator and high-speed camera, set the ignition energy, ignition delay time, gas inlet integral number and gas membrane breaking pressure of the ignition mechanism, select the dust accumulation mode and start the electromagnetic vibrating plate until the dust generation target accumulation mode is reached. S4. Let stand for 2 minutes until the dust accumulation pattern stabilizes. Then, evacuate the square pipe to the set vacuum level again and inject combustible gas into the gas explosion section. Use the circulation pump connected to the gas explosion section to automatically mix the gas for 5 minutes to ensure uniform concentration distribution. S5. Ignite the combustible gas in the gas explosion section. The explosion flame is accelerated by the flame acceleration ring. When the explosion pressure reaches the set pressure, the solenoid valve is opened to control the pressure of the gas explosion section. At the same time, the laser generator is controlled to shoot the laser vertically from the top of the square pipe to the bottom of the pipe. The high-speed camera is controlled to capture the motion of the particles under the shock wave and the flame propagation pattern during the explosion process. The sensor records the data and transmits it to the data acquisition and processing system. The data is recorded by the data acquisition and processing system. S6. After the experiment is completed, use Insight4G software to process the images captured by the high-speed camera to obtain the velocity cloud map of the particle motion. Open the pressure relief valve on the additional pipeline section to release the pressure, and clean the inside of the square pipeline to complete the test.

[0018] Compared with the prior art, the present invention has the following advantages: This invention comprises a test device consisting of an interconnected gas explosion section and a dust laying section. An additional pipeline section is vertically fixed at the tail end of the dust laying section for experimental research on secondary explosions of deposited dust under different working conditions. An ignition mechanism is installed at the front end of the gas explosion section to ignite the gas. A shock wave generating mechanism is installed within the gas explosion section near the ignition mechanism to accelerate the flame until the pressure reaches the set pressure. A data acquisition and processing system is used to collect and analyze image and pressure data during the test process in the gas explosion section and the dust laying section. It can be used for various experiments such as combustible gas explosion in pipelines, combustible dust explosion, shock wave-driven dust secondary explosion, explosion suppression, and explosion venting. By analyzing the influence of factors such as dust concentration, dust accumulation location and state, gas equivalence ratio, shock wave pressure, pipeline length and type, and diaphragm shape on the particle entrainment dynamics, explosion pressure, and macroscopic flame characteristics of the dust secondary explosion process, the invention explores the dynamic evolution process and coupling mechanism of dust particle entrainment-ignition-deflagration under shock wave induction. Attached Figure Description

[0019] Figure 1 This is a front view of the overall structure of the present invention; Figure 2 This is a top view of the overall structure of the invention; Figure 3 This is a line graph showing the maximum explosion pressure of aluminum powder with different dust concentrations undergoing secondary explosions induced by 25% hydrogen explosion in the experimental examples of this invention. Figure 4 In the experimental example of this invention, a 20% hydrogen explosion induced 1200 g / m³3 Curve showing the change in secondary explosion pressure of aluminum powder over time; Figure 5 In the experimental example of this invention, a 20% hydrogen explosion induced 1200 g / m³ 3 Pressure-flame coupling diagram of the secondary explosion process of high-concentration aluminum powder; Figure 6 In the experimental example of this invention, a 20% hydrogen explosion induced 1200 g / m³ 3 High-speed image of flame morphology evolution during a secondary explosion of high-concentration aluminum powder; Figure 7 In the experimental example of this invention, a 20% hydrogen explosion induced 1200 g / m³ 3 Particle motion diagram during the dust concentration dust hoisting process.

[0020] Explanation of reference numerals in the attached figures: 1-Gas explosion section; 2-Dust laying section; 3-Additional pipeline section; 4-Ignition mechanism; 5-Shock wave generating mechanism; 6-Solenoid valve. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] like Figure 1-2 As shown, the present invention provides a technical solution: a shock wave induced deposition dust secondary explosion flame flow field test device, comprising a gas explosion section 1 and a dust laying section 2 that are interconnected, an additional pipeline section 3, an ignition mechanism 4, a shock wave generating mechanism 5, and a data acquisition and processing system; In this embodiment, the additional pipe section 3 is vertically fixedly connected to the tail end of the dust laying section 2, and is used to complete the depressurization and exhaust treatment of the gas explosion section 1 and the dust laying section 2. The ignition mechanism 4 is installed at the front end of the gas explosion section 1 and is used to complete the gas ignition operation. The shock wave generating mechanism 5 is installed in the gas explosion section 1 near the ignition mechanism 4, and is used to accelerate the flame until the pressure reaches the set pressure. The data acquisition and processing system is specifically a computer with pre-installed Insight4G software, used to acquire and analyze image and pressure data during the testing process of gas explosion section 1 and dust laying section 2; it can be used for various experiments such as combustible gas explosion in pipelines, combustible dust explosion, shock wave dust secondary explosion, explosion suppression, and explosion venting.

[0023] By analyzing the influence of factors such as dust concentration, dust accumulation location and state, gas equivalence ratio, shock wave pressure, pipeline length and type, and diaphragm shape on the particle hoisting dynamics, explosion pressure, and macroscopic flame characteristics of the dust secondary explosion process, this study explores the dynamic evolution process and coupling mechanism of dust particle hoisting-ignition-deflagration under shock wave induction.

[0024] In this embodiment, an electromagnetic valve 6 is provided at the connection between the gas explosion section 1 and the dust laying section 2, and the electromagnetic valve 6 is connected to the data acquisition and processing system via a signal connection. As one possible implementation method in this embodiment, the solenoid valve 6 adopts a detachable modular design. After removing the electromagnetic drive unit of the solenoid valve 6, its valve body can be converted into a flange base with a through hole with a diameter of Φ of 60mm in the middle. The flange base is embedded with a standardized slot, which can install a customized film mold. The mold supports quick replacement of films of different materials and shapes.

[0025] As one possible implementation in this embodiment, the gas explosion section 1 and the dust laying section 2 are both square pipelines; The bottom surface of the square pipe is made of rigid material, and four transparent glass windows are equally spaced on the other three surfaces. The inner diameter of the transparent glass window is 11cm. A laser generator is connected to the top of the transparent glass window through a light guide arm. The laser generator vertically shoots the laser into the transparent glass window. A high-speed camera connected to the data acquisition and processing system is set on the front of the transparent glass window. The square pipe is also pre-set with sensor connection holes, through which data acquisition sensors are installed. The sensors are specifically pressure sensors, temperature sensors, or light intensity sensors, and the sensors are also connected to the data acquisition and processing system.

[0026] As one possible implementation in this embodiment, the wall thickness of the square pipeline is 15mm and the pressure bearing capacity is greater than 20MPa; the flame acceleration section of the gas explosion section 1 is 0.5m and the shock wave propagation section is 1.5m, and the total length of the gas explosion section 1 and the dust laying section 2 is 5m.

[0027] As one possible implementation method in this embodiment, a programmable electromagnetic vibration plate with a length of 20cm and a width of 12cm is embedded at the bottom of the dust laying section 2. During testing, the frequency can be adjusted to make the dust generate different accumulation patterns.

[0028] In this embodiment, the stacking morphology is specifically a uniform thin layer, a ring-shaped stacking, a mound-shaped stacking, a layered structure, or a corner aggregation morphology; Specifically, the uniform thin layer is produced by synchronous vibration of the entire plate, with a frequency range of 60-80Hz and a vibration time of 10-15s. The annular stacking uses edge-reinforced vibration with a frequency range of 8-12Hz and a vibration time of 20-30s. The mound-like accumulation was subjected to centrally focused vibration with a frequency range of 15-20Hz and a vibration time of 15-20s. The layered structure adopts an alternating low- and high-frequency vibration mode, with a high frequency of 40-50Hz and a low frequency of 5-10Hz, and a vibration time of 30s. The corner cluster pattern adopts a diagonal asymmetric vibration mode with a frequency range of 25-30Hz and a vibration time of 25s.

[0029] As one possible implementation of this embodiment, the ignition mechanism 4 consists of a vacuum pump, a gas cylinder, a ball valve and an ignition electrode connected in sequence. The ignition electrode is specifically composed of two copper welding rods with a diameter of 5mm arranged opposite each other, and the distance between the two copper welding rods is no more than 6mm.

[0030] As one possible implementation in this embodiment, the shock wave generating mechanism 5 is specifically a flame acceleration ring or a shock wave generator. When the flame acceleration ring is used in conjunction with the solenoid valve, the shock wave pressure output by the solenoid valve is controlled by the solenoid valve and used to study the interaction between combustible gas and deposited dust. When the shock wave generator is used in conjunction with a thin film embedded in flanges of different shapes, the shock wave generator controls the output shock wave pressure to study the interaction between shock waves and deposited dust. Solenoid valves cannot control the shape of the explosion vent, but flanges can. The flame acceleration ring and the shock wave generator share a common base for easy disassembly. The flame acceleration ring has an inner diameter of 100mm, an obstacle blocking ratio of 0.6, and a combustible gas cylinder is connected to the outside of the flame acceleration ring. The shock wave generator is connected to an air cylinder.

[0031] As one possible implementation method in this embodiment, the additional pipe section 3 is connected to the dust laying section 2 through a four-way pipe, and the additional pipe section 3 is also provided with a transparent glass window and a pressure relief valve.

[0032] The testing method of the shock wave-induced deposition dust secondary explosion flame flow field testing device in this embodiment includes the following steps: S1. Assemble the gas explosion section 1, dust laying section 2, additional pipeline section 3, ignition mechanism 4, shock wave generating mechanism 5, and data acquisition and processing system according to the experimental plan, and perform corresponding debugging and settings. S2. Select the dust laying position in dust laying section 2, place a certain amount of dust in dust laying section 2, use a vacuum pump to evacuate the square pipeline to a low vacuum degree of less than 1 kPa, observe and confirm that the seal is good, open the vent valve, and close the vent valve after the pressure in the square pipeline returns to normal. S3. Open the preset Insight4G software in the data acquisition and processing system, adjust the parameters of the laser generator and high-speed camera, set the ignition energy, ignition delay time, gas inlet integral number and gas membrane breaking pressure of the ignition mechanism 4, select the dust accumulation mode and start the electromagnetic vibrating plate until the dust generation target accumulation mode is reached. S4. Let stand for 2 minutes until the dust accumulation pattern stabilizes. Then, evacuate the square pipe to the set vacuum level again and inject combustible gas into the gas explosion section 1. Use the circulation pump connected to the gas explosion section 1 to automatically mix the gas for 5 minutes to ensure uniform concentration distribution. S5. Ignite the combustible gas in the gas explosion section 1. The explosion flame is accelerated by the flame acceleration ring. When the explosion pressure reaches the set pressure, open the solenoid valve 6 to control the pressure of the gas explosion section. At the same time, control the laser generator to shoot the laser vertically from the top of the square pipe to the bottom of the pipe. Control the high-speed camera to capture the motion of the particles under the shock wave and the flame propagation pattern during the explosion process. The sensor records the data and transmits it to the data acquisition and processing system. The data is recorded by the data acquisition and processing system. S6. After the experiment is completed, the images captured by the high-speed camera are processed to obtain the velocity cloud map of the particle motion. The pressure relief valve on the additional pipe section 3 is opened to release the pressure, and the inside of the square pipe is cleaned to complete the test operation.

[0033] In the experiment, taking 300-mesh aluminum powder as an example, we analyzed its explosion pressure under hydrogen explosion and used a high-speed camera to capture the flame shape changes during the secondary explosion of aluminum powder. Four pressure sensors were set at 77cm, 182cm, 220cm and 330cm in the dust laying section 2. The corresponding labels of the pressure sensors are P1, P2, P3 and P4. like Figure 3 As shown, aluminum powder of different concentrations was piled up in the transparent glass window corresponding to P3, and the maximum explosion pressure of the secondary explosion was tested using 25% hydrogen gas. The test results show that... When the aluminum powder concentration is 400 g / m 3 At that time, the maximum explosion pressure in the pipeline was 0.624 MPa; When the aluminum powder concentration is 800 g / m 3 At that time, the maximum explosion pressure in the pipeline was 0.641 MPa; When the aluminum powder concentration is 1200 g / m³ 3At that time, the maximum explosion pressure in the pipeline was 0.677 MPa; When the aluminum powder concentration is 1600 g / m³ 3 At that time, the maximum explosion pressure in the pipeline was 0.613 MPa; And through Figure 3 It can be observed that when the dust concentration is 1200 g / m³ 3 The highest pressure indicates that at this concentration, the dust cloud formed by the hydrogen explosion-induced aluminum powder dust cloud reached the optimal explosion concentration.

[0034] Figure 4 The image shows aluminum powder laid on the transparent glass window corresponding to P4, with a 20% hydrogen explosion induction rate of 1200 g / m³. 3 Curve showing the change in secondary explosion pressure of aluminum powder over time; At this point, it becomes clear that all four pressure sensors exhibit two distinct pressure peaks over time. The primary explosion pressure peaks for P1-P4 are 0.416 MPa, 0.381 MPa, 0.399 MPa, and 0.28 MPa, respectively; while the secondary explosion pressure peaks are 0.49 MPa, 0.483 MPa, 0.481 MPa, and 0.482 MPa, respectively.

[0035] The pressure / time graph shows a significant time delay between the primary and secondary explosions, and the pressure of the secondary explosion is significantly greater than that of the primary explosion.

[0036] Figure 5 It is a 20% hydrogen explosion-induced 1200g / m³ 3 Pressure-flame coupling image of the secondary explosion process of high-concentration aluminum powder; When the pressure reaches the first peak, the flame appears dark yellow. At this time, only a small amount of suspended dust in the pipe is ignited by the shock wave generated by the hydrogen explosion. As time goes on, the shock wave sweeps across the dust layer and lifts up the dust deposited in the pipe, forming a cloud of highly concentrated combustible dust. At this time, the pressure reaches the second peak and the flame appears bright yellow.

[0037] Figure 6 It is a 20% hydrogen explosion-induced 1200g / m³ 3 High-speed images of the flame morphology evolution throughout the entire process of a secondary explosion of concentrated aluminum powder reflect the evolution of the flame morphology from hydrogen ignition to aluminum powder explosion. These images can be coupled with pressure and dust particle transport to study the formation mechanism of the gas-solid two-phase secondary explosion disaster chain.

[0038] Figure 7 The explosion was captured by a high-speed camera, showing a 20% hydrogen gas explosion inducing a 1200g / m³ atmosphere. 3To investigate the particle movement patterns during the dust dust swirl process, 300-mesh alumina powder was used as tracer particles, and the dust accumulated in the transparent glass window corresponding to P4.

[0039] Within the transparent glass window surrounding the dust release point P4, the concentration of dust being swept up is relatively high, but the concentration is uneven. In contrast, near the transparent glass window corresponding to P3, the dust concentration is more uniform, but the dust concentration is lower.

[0040] The processed velocity cloud map further shows that the average velocity distribution of dust particles in P3 is relatively uniform, and some uniformly distributed eddies are formed in local areas. In contrast, the particles near the transparent glass window in P4 have a larger velocity and show an upward and leftward trend.

[0041] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0042] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A test apparatus for a shock-induced deposition dust deflagration flame flow field, characterized by: It comprises a gas explosion section (1) and a dust laying section (2) connected through each other; An ignition mechanism (4) is installed at the front end of the gas explosion section (1); A shock wave generating mechanism (5) is installed in the gas explosion section (1) near the ignition mechanism (4); A data acquisition and processing system, specifically a computer with preset processing software, is used to acquire image and pressure data during the test of the gas explosion section (1) and the dust laying section (2) and to analyze and process them; An additional pipeline section (3) is vertically fixed and connected at the tail end of the dust laying section (2) to assemble with the gas explosion section (1) and the dust laying section (2) into a curved pipe or T-shaped pipe shape for experiments under different working conditions.

2. The test apparatus of claim 1, wherein, An electromagnetic valve (6) is arranged at the connection between the gas explosion section (1) and the dust laying section (2) and is signal connected with the data acquisition and processing system.

3. The test apparatus of claim 2, wherein, The gas explosion section (1) and the dust laying section (2) are square pipelines respectively; The bottom surface of the square pipeline is made of rigid material, and four transparent glass windows are arranged on the other three surfaces at equal intervals, the inner diameter of the transparent glass window is 11 cm, a laser generator is connected to the transparent glass window through a light guide arm, laser is vertically shot into the transparent glass window through the laser generator, and a high-speed camera is arranged on the front surface of the transparent glass window and is signal connected with the data acquisition and processing system; A sensor connection hole is also preset on the square pipeline to install a data acquisition sensor, and the sensor is also signal connected with the data acquisition and processing system.

4. The test apparatus of claim 3, wherein, The wall thickness of the square pipeline is 15 mm, and the pressure bearing capacity is greater than 20 MPa; the flame acceleration section in the gas explosion section (1) is 0.5 m, the shock wave propagation section is 1.5 m, and the total length of the gas explosion section (1) and the dust laying section (2) is 5 m.

5. The test apparatus of claim 4, wherein, A programmable electromagnetic vibration plate with a length of 20 cm and a width of 12 cm is embedded in the bottom of the dust laying section (2), and different accumulation forms of dust can be generated by adjusting the frequency during the test.

6. The test apparatus of claim 5, wherein, The accumulation forms are specifically uniform thin layer, ring-shaped accumulation, hill-shaped accumulation, layered structure or corner gathering form.

7. The test apparatus of claim 1, wherein, The ignition mechanism (4) is composed of a vacuum pump, a gas cylinder, a ball valve and an ignition electrode connected in sequence, the ignition electrode is specifically composed of two oppositely arranged copper welding rods with a diameter of 5 mm, and the distance between the two copper welding rods is not greater than 6 mm.

8. The test apparatus of claim 1, wherein, The shock wave generating mechanism (5) is specifically a flame acceleration ring or an impact wave generator; The inner diameter of the flame acceleration ring is 100 mm, and the obstacle blockage ratio is 0.6; The impact wave generator is circumscribed with a gas cylinder.

9. The test apparatus of claim 1, wherein, The additional pipeline section (3) is connected with the dust laying section (2) through a four-way pipeline, and the additional pipeline section (3) is also provided with a transparent glass window and a pressure relief valve, and a programmable electromagnetic vibration plate is arranged on the inner bottom surface of the additional pipeline section (3).

10. The test method of claim 1-9, wherein, It comprises the following steps: S1, according to the experimental scheme, assemble the gas explosion section (1), the dust laying section (2), the additional pipeline section (3), the ignition mechanism (4), the shock wave generating mechanism (5) and the data acquisition and processing system, and carry out corresponding debugging and setting; S2, select the position of dust laying in the dust laying section (2), place the quantitative dust in the dust laying section (2), use the vacuum pump to vacuum the square pipeline to less than 1kpa low vacuum degree, after standing and observing to confirm good sealing, open the air release valve, until the square pipeline restores to normal pressure, close the air release valve after restoring to normal pressure; S3, open the preset insight4G software in the data acquisition and processing system, adjust the parameters of the laser generator and the high-speed camera, set the ignition energy, ignition delay time, gas volume fraction and gas membrane breaking pressure of the ignition mechanism (4), select the accumulation form of the dust, start the electromagnetic vibration plate until the dust forms the target accumulation form; S4, stand for 2min, after the accumulation form of the dust is stable, vacuum the square pipeline to the set vacuum degree again, inject combustible gas into the gas explosion section (1), automatically mix the gas for 5min by using the circulating pump connected to the gas explosion section (1), to ensure uniform concentration distribution; S5, ignite the combustible gas in the gas explosion section (1), the explosion flame is accelerated through the flame acceleration ring, when the explosion pressure reaches the set pressure, open the electromagnetic valve (6), realize the control of the gas explosion section pressure, at the same time, control the laser generator to vertically shoot laser from the top of the square pipeline to the bottom of the pipeline, control the high-speed camera to shoot the movement form of the particles hoisted under the induction of shock wave and the flame propagation form of the explosion process, the sensor records the data and transmits it into the data acquisition and processing system, record the data through the data acquisition and processing system; S6, after the experiment is completed, process the high-speed camera image to obtain the velocity cloud image of the particle motion, open the pressure relief valve on the additional pipeline section (3) to release the pressure, and clean the inside of the square pipeline, complete the test operation.

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