Dust explosion flame free radical test system and test method

Abstract

The invention discloses a dust explosion flame free radical testing system and a testing method, belongs to the technical field of dust explosion testing, and solves the problem that existing testing equipment cannot realize visual testing of combustion flame free radicals at the initial stage of dust explosion ignition and in the development process. According to the solution, the test system comprises an explosion generation assembly used for generating single-side open type dust cloud explosion, an optical observation assembly used for observing flame free radicals, a control system, a computer and an air compressor, and semi-open type dust cloud is formed through the explosion generation assembly and is ignited and detonated; images of different free radicals changing along with flame are collected through the optical observation assembly, and visual observation, recording and analysis are carried out through the computer. The system has the advantages of being high in functionality, integrated in system, easy to operate and safe and reliable in experiment process and is suitable for various kinds of combustible dust, collected data can promote dust explosion mechanism research, and data support is provided for development of dust explosion optical early warning protection measures.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of dust explosion testing, and particularly relates to a dust explosion flame free radical testing system and a testing method. BACKGROUND

[0002] Dust explosion is one of the major hazards in industrial production, and the change of flame free radicals during the development of combustion and explosion, especially the change of free radicals in the initial stage of ignition, is a key factor affecting the development of explosion and a focus of attention in the prevention and control of combustion and explosion. By optical detection technology, the characteristic free radical change of the flame in the initial stage of combustion and explosion of the detected substance can be obtained, and these free radical characteristics can be monitored online, so that wide-area and high-speed combustion and explosion early warning can be realized. This technology has been widely used in the field of gas and oil fire and explosion prevention.

[0003] In the field of dust explosion, dust needs to be in certain constraints to reach the explosion condition, but the traditional test device (such as Hartmann tube and 20L explosion sphere) has an outer shell or glass barrier, which makes it difficult to directly obtain the characteristics of free radical change during the development of flame, especially in the initial stage of ignition. SUMMARY

[0004] The main purpose of the present application is to overcome the shortcomings of the prior art, and to provide a dust explosion flame free radical testing system and a testing method, so as to solve the problem that the existing test equipment cannot realize the visual testing of combustion flame free radicals in the initial stage of dust explosion ignition and the development process.

[0005] The present application is realized by the following technical solutions: A dust explosion flame free radical testing system, which comprises an explosion generating assembly for generating a single-side open dust cloud explosion, an optical observation assembly for observing flame free radicals, a control system, a computer and an air compressor, wherein: the explosion generating assembly, the optical observation assembly and the computer are sequentially arranged above a test table, the air compressor is arranged on the test table below the explosion generating assembly, and the air compressor is communicated with the explosion generating assembly through a pipeline; the control system is arranged on the test table below the optical observation assembly and the computer, the control system is electrically connected with the explosion generating assembly, the optical observation assembly, the computer and the air compressor through data lines, the control system is operated by selecting software installed in the computer to realize the synchronous control of the explosion generating assembly, the optical observation assembly and the air compressor, and the free radical change data collected by the optical observation assembly is stored in the computer; The explosion generating assembly comprises a sleeve, a pneumatic ignition assembly and a dust dispersion base assembly, an opening is arranged on the side wall of the sleeve opposite to the optical observation assembly, first and second electrode mounting openings are symmetrically arranged on the side walls of the sleeve opposite to the opening, first and second sliding grooves are respectively arranged on the end faces of the sleeve on the two sides of the opening in the vertical direction, first and second arc-shaped transparent plates are arranged in parallel and inserted at the opening position, and the first and second arc-shaped transparent plates are respectively movably inserted into the corresponding first and second sliding grooves, and the lower end faces of the sleeve, the first arc-shaped transparent plate and the second arc-shaped transparent plate are detachably inserted into the annular chuck; The pneumatic ignition assembly comprises a pneumatic electrode, a fixed electrode, pneumatic electrode driving pipes and electrode bases, the contact ends of the pneumatic electrode and the fixed electrode are respectively inserted into the sleeve through the first and second electrode mounting openings, the middle part of the pneumatic electrode is connected with the gas supply assembly through two pneumatic electrode driving pipes, and the tail end of the pneumatic electrode is electrically connected with the high-voltage power module in the control system through a high-voltage circuit cable; the contact end of the fixed electrode is inserted into the sleeve through the second electrode mounting opening, and the tail end of the fixed electrode is grounded through a high-voltage circuit cable; The dust dispersion base assembly comprises a dispersion nozzle, a powder containing chamber, a sliding connecting rod, a transmission module, electric control gears and a base shell, the powder containing chamber is fixedly installed at the center of the base shell, combustible dust for dust explosion experiment is contained in the powder containing chamber, the dispersion nozzle is arranged vertically upward at the center of the powder containing chamber, and the upper end of the dispersion nozzle extends to the bottom of the sleeve through the annular chuck; the electric control gears are symmetrically arranged in the base shell below the powder containing chamber, and the two electric control gears rotate synchronously and in the same direction; the transmission module is arranged above the two electric control gears, and comprises two parallel arranged racks and a connecting block connecting the roots of the two racks, the two racks and the connecting block form a C-shaped structure, the racks are respectively engaged with the corresponding electric control gears, a limiting sliding groove is arranged on the connecting block, and an arc-shaped limiting groove is arranged on the base shell near one side of the limiting sliding groove; the sliding connecting rod is arranged in a Z-shaped structure, one end of the sliding connecting rod is installed vertically downward in the limiting sliding groove, and the other end of the sliding connecting rod is vertically upward and fixedly connected with the lower edges of the corresponding first and second arc-shaped transparent plates through the arc-shaped limiting groove, the electric control gears drive the transmission module to drive the sliding connecting rod to reciprocate along the arc-shaped limiting groove, thereby driving the first and second arc-shaped transparent plates to be synchronously opened or closed; The air supply assembly comprises an air supply assembly shell, an electromagnetic valve, a powder spraying gas chamber and a driving gas chamber arranged in the air supply assembly shell, and the base shell is fixedly installed on the outer wall of the air supply assembly shell, and the compressed air outlet of the air compressor is connected in parallel with the powder spraying gas chamber and the driving gas chamber through the air pipe; the first electromagnetic valve is installed on one side of the air inlet pipe of the powder spraying gas chamber, the powder spraying gas chamber is connected with the dispersion nozzle on one side of the air outlet pipe of the powder spraying gas chamber, and the second electromagnetic valve is installed on one side of the air outlet pipe of the powder spraying gas chamber; the third electromagnetic valve is installed on one side of the air inlet pipe of the driving gas chamber, the driving gas chamber is connected with the pneumatic electrode on one side of the air outlet pipe of the driving gas chamber, and the fourth electromagnetic valve is installed on one side of the air outlet pipe of the driving gas chamber.

[0006] Further, the optical observation assembly comprises a narrow-band filter and a high-speed CCD camera, the narrow-band filter is installed in front of the lens of the high-speed CCD camera, and the high-speed CCD camera is electrically connected with the control system and the computer through data lines.

[0007] Further, the passing bandwidth of the narrow-band filter is 10 nm, and the center wavelength is determined according to the observed free radicals.

[0008] Further, the control system comprises a PLC module, a power supply module, a high-voltage power supply module, a grounding module and a communication module integrated in the control box.

[0009] A method for testing dust explosion flame free radicals by using the test system described above, comprising the following steps: S1, installation and inspection of the test device: according to the free radicals to be observed, a narrow-band filter with a corresponding wavelength is selected, and then the experimental device is assembled, the air supply line and the control line are installed, and the overall test system is installed and debugged; S2, laying combustible dust: first, the electric control gear controls the first arc-shaped transparent plate and the second arc-shaped transparent plate to slide into the corresponding first sliding slot and second sliding slot through the sliding connecting rod and transmission module, and the opening is in the open state; then, a certain amount of combustible dust is weighed and evenly laid on the bottom of the powder container; finally, the sliding connecting rod and the transmission module control the first arc-shaped transparent plate and the second arc-shaped transparent plate to reset, and the opening is in the closed state; S3, inflation: the control system controls the first electromagnetic valve and the third electromagnetic valve to be in the open state respectively, and the air compressor charges compressed air into the powder spraying gas chamber and the driving gas chamber respectively, and when the air pressure in the powder spraying gas chamber and the driving gas chamber reaches a predetermined value, the first electromagnetic valve and the third electromagnetic valve are closed; S4, forming a single-sided open dust cloud: the control system controls the second electromagnetic valve to open, high-pressure compressed air in the powder spraying chamber is sprayed out of the dispersion nozzle, and the combustible dust in the powder chamber is blown up to form a dust cloud that spreads upward; at the same time, the electric control gear controls the first arc-shaped transparent plate and the second arc-shaped transparent plate to slide into the corresponding first sliding groove and second sliding groove again through the sliding connecting rod and transmission module, and the opening is in the open state again, at this time, a single-sided open dust cloud is formed in the sleeve; S5, electrostatic ignition: the control system controls the fourth electromagnetic valve to open, and at the same time, the pneumatic electrode in the sleeve is close to the fixed electrode side, the air is broken to generate electrostatic spark, and then the dust cloud is ignited; S6, data acquisition: the optical observation assembly collects the flame free radical data during the explosion process and transmits it to the computer for visual display and storage; S7, device cleaning: after the pneumatic electrode is returned to the home position, the remaining static electricity in the capacitor is released, and then the residual dust and combustion products on the test device are cleaned; after the experiment is finished, the power is turned off, the device is disassembled and cleaned, and each component is ready for the next cycle.

[0010] The beneficial effects of the present application are: The present application can form a directly observable dust cloud and ignite it by controlling the opening and closing actions of the first arc-shaped transparent plate and the second arc-shaped transparent plate, and can collect images of different free radical changes from the ignition start to the flame development process through the optical observation assembly with replaceable different bandwidth narrow band filters, and can control the whole test process through the control system and visualize the data through the computer.

[0011] In summary, the present application can form a directly observable combustible dust cloud in a single-sided open space and ignite it, can obtain the development and change of specific free radicals from the initial ignition to the development process, has the advantages of strong functionality, system integration, simple operation, safe and reliable experimental process, is suitable for various combustible dust, and the collected data can promote the research on dust explosion mechanism and provide data support for the development of optical early warning and protection measures for dust explosion. BRIEF DESCRIPTION OF DRAWINGS

[0012] Figure 1 It is a schematic diagram of the overall structure of the test device of the present application; Figure 2 It is an exploded view of the pneumatic ignition assembly and the dust dispersion base assembly; Figure 3 It is an enlarged schematic diagram of the three-dimensional structure of the dust dispersion base assembly (omitting the dispersion nozzle and the powder chamber); Figure 4 It is a structure principle diagram of the gas supply assembly; Figure 5 It is a structure schematic diagram of the optical observation assembly.

[0013] In the figure, 1 is an explosion generating assembly, 101 is a sleeve, 102 is a first curved transparent plate, 103 is a second curved transparent plate, 104 is an annular chuck, 105 is a pneumatic electrode, 106 is a fixed electrode, 107 is an electrode base, 108 is a dispersion nozzle, 109 is a powder holding chamber, 110 is a sliding connecting rod, 111 is a transmission module, 112 is an electronically controlled gear, 113 is a base housing, 114 is a first solenoid valve, 115 is a second solenoid valve, 116 is a third solenoid valve, 117 is a fourth solenoid valve 117, 118 is a powder spraying air storage chamber, 119 is a drive air storage chamber, and 120 is an air supply assembly housing; 2 is an optical observation component, 201 is a narrow-band filter, and 202 is a high-speed CCD camera; 3 is a control system, 4 is a computer, and 5 is an air compressor. DETAILED DESCRIPTION

[0014] The present invention will be described in further detail below with reference to the accompanying drawings and examples.

[0015] like Figures 1 to 5 A dust explosion flame radical test system is shown, which includes an explosion generation component 1 for generating a single-sided open dust cloud explosion, an optical observation component 2 for observing flame free radicals, a control system 3, a computer 4 and an air compressor 5, wherein: the explosion generation component 1, the optical observation component 2 and the computer 4 are arranged in sequence above the test bench, and the air compressor 5 is arranged on the test bench below the explosion generation component 1, and the air compressor 5 is connected to the explosion generation component 1 through a pipeline; the control system 3 is arranged on the test bench below the optical observation component 2 and the computer 4, and the control system 3 is electrically connected to the explosion generation component 1, the optical observation component 2, the computer 4 and the air compressor 5 through data cables. By selecting the software installed in the computer 4 to operate the control system 3, synchronous control of the explosion generation component 1, the optical observation component 2 and the air compressor 5 is achieved, and the free radical change data collected by the optical observation component 2 is stored in the computer 4; The explosion generation assembly 1 includes a sleeve 101, a pneumatic ignition assembly and a dust dispersion base assembly. An opening is provided on the side wall of the sleeve 101 opposite to the optical observation assembly 2. A first electrode mounting opening and a second electrode mounting opening are symmetrically provided on the side wall of the sleeve 101 opposite to the opening. A first slide groove and a second slide groove are respectively provided on the end surfaces of the sleeve 101 on both sides of the opening in the vertical direction. The first curved transparent plate 102 and the second curved transparent plate 103 are arranged in parallel and inserted at the opening position, and the first curved transparent plate 102 and the second curved transparent plate 103 are respectively movably inserted into the corresponding first slide groove and the second slide groove. The lower end surfaces of the sleeve 101, the first curved transparent plate 102 and the second curved transparent plate 103 are detachably inserted on the annular chuck 104. The gas dynamic ignition assembly comprises a gas dynamic electrode 105, a fixed electrode 106, gas dynamic electrode driving pipes and an electrode base 107, the gas dynamic electrode 105 and the fixed electrode 106 are respectively installed on the corresponding electrode base 107; the contact end of the gas dynamic electrode 105 is inserted into the sleeve 101 by the first electrode mounting port, the middle part of the gas dynamic electrode 105 is connected with the gas supply assembly through two gas dynamic electrode driving pipes, and the end of the gas dynamic electrode 105 is electrically connected with the high-voltage power module in the control system 3 through a high-voltage circuit cable; the contact end of the fixed electrode 106 is inserted into the sleeve 101 by the second electrode mounting port, and the end of the fixed electrode 106 is grounded through a high-voltage circuit cable; The dust dispersion base assembly comprises a dispersion nozzle 108, a powder containing chamber 109, a sliding connecting rod 110, a transmission module 111, an electric control gear 112 and a base shell 113, the powder containing chamber 109 is fixedly installed at the center of the base shell 113, the combustible dust used for the dust explosion experiment is contained in the powder containing chamber 109, the dispersion nozzle 108 is vertically upwardly arranged at the center of the powder containing chamber 109, and the upper end of the dispersion nozzle 108 extends to the bottom of the sleeve 101 through the annular chuck 104; the electric control gears 112 are symmetrically arranged in the base shell 113 below the powder containing chamber 109, and the two electric control gears 112 rotate synchronously and in the same direction; the transmission module 111 is arranged above the two electric control gears 112, the transmission module 111 comprises two parallel arranged racks and a connecting block connecting the roots of the two racks, the two racks and the connecting block form a C-shaped structure, the racks are respectively engaged with the corresponding electric control gears 112, a limiting sliding groove is arranged on the connecting block, and an arc-shaped limiting groove is arranged on the base shell 113 near one side of the limiting sliding groove; the sliding connecting rod 110 is arranged in a Z-shaped structure, one end of the sliding connecting rod 110 is vertically downwardly installed in the limiting sliding groove, and the other end of the sliding connecting rod 110 is vertically upwardly arranged through the arc-shaped limiting groove and is fixedly connected with the lower edge of the corresponding first arc-shaped transparent plate 102 and second arc-shaped transparent plate 103, the electric control gears 112 drive the transmission module 111 to drive the sliding connecting rod 110 to reciprocatingly slide along the arc-shaped limiting groove, thereby driving the first arc-shaped transparent plate 102 and the second arc-shaped transparent plate 103 to synchronously open or close; The air supply assembly comprises an air supply assembly shell 120, and an electromagnetic valve, a powder spraying gas chamber 118 and a driving gas chamber 119 arranged in the air supply assembly shell 120, and the base shell 113 is fixedly installed on the outer wall of the air supply assembly shell 120, and the compressed air outlet of the air compressor 5 is connected in parallel with the powder spraying gas chamber 118 and the driving gas chamber 119 through air pipes; the first electromagnetic valve 114 is installed on one side of the air inlet pipe of the powder spraying gas chamber 118, the powder spraying gas chamber 118 is connected with the dispersion nozzle 108 on one side of the air outlet pipe of the powder spraying gas chamber 118, and the second electromagnetic valve 115 is installed on one side of the air outlet pipe of the powder spraying gas chamber 118; the third electromagnetic valve 116 is installed on one side of the air inlet pipe of the driving gas chamber 119, the driving gas chamber 119 is connected with the pneumatic electrode 105 on one side of the air outlet pipe of the driving gas chamber 119, and the fourth electromagnetic valve 117 is installed on one side of the air outlet pipe of the driving gas chamber 119.

[0016] Further, the optical observation assembly 2 comprises a narrow-band filter 201 and a high-speed CCD camera 202, the narrow-band filter 201 is installed on the front side of the lens of the high-speed CCD camera 202, and the high-speed CCD camera 202 is electrically connected with the control system 3 and the computer 4 through data lines.

[0017] Further, the passing bandwidth of the narrow-band filter 201 is 10 nm, and the center wavelength is determined according to the observed free radicals.

[0018] Further, the control system 3 comprises a PLC module, a power supply module, a high-voltage power supply module, a grounding module and a communication module integrated in a control box.

[0019] A method for testing dust explosion flame free radicals by using the test system described above, comprising the following steps: S1, installation and inspection of the test device: according to the free radicals to be observed, a narrow-band filter 201 with a corresponding wavelength is selected, and then the experimental device is assembled, the air supply line and the control line are installed, and the overall test system is installed and debugged; S2, laying combustible dust: first, the electric control gear 112 controls the first arc-shaped transparent plate 102 and the second arc-shaped transparent plate 103 to be slid into the corresponding first sliding slot and second sliding slot through the sliding connecting rod 110 and the transmission module 111, and the opening is in the open state; then, a certain amount of combustible dust is weighed and evenly laid on the bottom of the powder container 109; finally, the sliding connecting rod 110 and the transmission module 111 control the first arc-shaped transparent plate 102 and the second arc-shaped transparent plate 103 to reset, and the opening is in the closed state; S3, inflation: control system 3 controls the first solenoid valve 114 and the third solenoid valve 116 to be in the open state respectively, and the air compressor 5 fills the compressed air into the powder injection chamber 118 and the driving chamber 119 respectively, when the air pressure in the powder injection chamber 118 and the driving chamber 119 reaches the predetermined value, the first solenoid valve 114 and the third solenoid valve 116 are closed; S4, form a single-sided open dust cloud: control system 3 controls the second solenoid valve 115 to open, the high-pressure compressed air in the powder injection chamber 118 is sprayed out by the dispersion nozzle 108, and the combustible dust in the powder chamber 109 is blown up to form an upwardly diffusing dust cloud; at the same time, the electric control gear 112 controls the first arc-shaped transparent plate 102 and the second arc-shaped transparent plate 103 to be slid into the corresponding first sliding slot and second sliding slot respectively through the sliding connecting rod 110 and the transmission module 111, and the opening is in the open state again, at this time, a single-sided open dust cloud is formed in the sleeve 1; S5, electrostatic ignition: control system 3 controls the fourth solenoid valve 117 to open, at the same time, the pneumatic electrode 105 in the sleeve 1 is close to the fixed electrode 106 side, the air is broken to produce electrostatic spark and then ignite the dust cloud; S6, data acquisition: the optical observation assembly 2 collects the flame free radical data in the explosion process and transmits it to the computer 4 for visual display and storage, and the number of free radicals in each region of the flame can be obtained by image processing; different filters can be replaced during the experiment to repeat the experiment several times, and then the development and change process of various free radicals with the flame can be obtained; S7, device cleaning: after the pneumatic electrode 105 is returned to the home position, the remaining static electricity in the capacitor is released, and then the residual dust and combustion products on the test device are cleaned; after the experiment is finished, the power is turned off, the device is disassembled and the components are cleaned for next cycle use.

[0020] The above is only a specific embodiment of the present application, but the protection scope of the present application is not limited thereto, any skilled person in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A dust explosion flame radical test system comprising an explosion generating assembly (1) for generating a single-sided open dust cloud explosion, an optical observation assembly (2) for observing flame radicals, a control system (3), a computer (4) and an air compressor (5), characterized in that: The explosion generation component (1), the optical observation component (2) and the computer (4) are sequentially arranged above the test bench, and the air compressor (5) is arranged on the test bench below the explosion generation component (1). The air compressor (5) is connected to the explosion generation component (1) through a pipeline; the control system (3) is arranged on the test bench below the optical observation component (2) and the computer (4), and the control system (3) is electrically connected to the explosion generation component (1), the optical observation component (2), the computer (4) and the air compressor (5) through data lines. By selecting the software installed in the computer (4) to operate the control system (3), the explosion generation component (1), the optical observation component (2) and the air compressor (5) are synchronously controlled, and the free radical change data collected by the optical observation component (2) is stored in the computer (4); The explosion generation component (1) includes a sleeve (101), a pneumatic ignition component and a dust dispersion base component, an opening is provided on the side wall of the sleeve (101) opposite to the optical observation component (2), a first electrode mounting opening and a second electrode mounting opening are symmetrically provided on the side wall of the sleeve (101) opposite to the opening, a first slide groove and a second slide groove are respectively provided on the end surface of the sleeve (101) on both sides of the opening in the vertical direction, a first curved transparent plate (102) and a second curved transparent plate (103) are arranged in parallel and inserted at the opening position, and the first curved transparent plate (102) and the second curved transparent plate (103) are respectively movably inserted in the corresponding first slide groove and second slide groove, and the lower end surfaces of the sleeve (101), the first curved transparent plate (102) and the second curved transparent plate (103) are detachably inserted on the annular chuck (104); The pneumatic ignition assembly comprises a pneumatic electrode (105), a fixed electrode (106), a pneumatic electrode drive tube and an electrode base (107), wherein the pneumatic electrode (105) and the fixed electrode (106) are respectively mounted on the corresponding electrode base (107); the contact end of the pneumatic electrode (105) is inserted into the sleeve (101) through the first electrode mounting port, the middle portion of the pneumatic electrode (105) is connected to the air supply assembly through two pneumatic electrode drive tubes, and the end of the pneumatic electrode (105) is electrically connected to the high-voltage power supply module in the control system (3) through a high-voltage circuit cable; the contact end of the fixed electrode (106) is inserted into the sleeve (101) through the second electrode mounting port, and the end of the fixed electrode (106) is grounded through the high-voltage circuit cable; The dust dispersion base assembly includes a dispersion nozzle (108), a powder holding chamber (109), a sliding connecting rod (110), a transmission module (111), an electric control gear (112) and a base shell (113). The powder holding chamber (109) is fixedly installed on the core of the base shell (113). The combustible dust used for the dust explosion experiment is contained in the powder holding chamber (109). The dispersion nozzle (108) is vertically upwardly arranged in the core of the powder holding chamber (109). The upper end of the dispersion nozzle (108) passes through the annular chuck (104) and extends to the bottom of the sleeve (101); the electric control gear (112) is symmetrically arranged in the base shell (113) below the powder holding chamber (109), and the electric control gears (112) on both sides rotate synchronously and in the same direction; the transmission module (111) is arranged above the electric control gears (112) on both sides. The transmission module (111) includes The invention comprises racks arranged in parallel on both sides and connecting blocks connecting the roots of the racks on both sides, the racks on both sides and the connecting blocks form a C shape, the racks are respectively engaged with the corresponding electric control gears (112), a limiting slot is provided on the connecting block, and an arc-shaped limiting slot is provided on the base shell (113) near the limiting slot; the sliding link (110) is arranged in a Z shape, one end of the sliding link (110) is vertically downwardly installed in the limiting slot, and the other end of the sliding link (110) vertically upwardly penetrates the arc-shaped limiting slot and is respectively fixedly connected to the lower side edges of the corresponding first arc-shaped transparent plate (102) and the second arc-shaped transparent plate (103); the electric control gear (112) drives the transmission module (111) to drive the sliding link (110) to slide back and forth along the arc-shaped limiting slot, thereby driving the first arc-shaped transparent plate (102) and the second arc-shaped transparent plate (103) to open or close synchronously; The air supply assembly comprises an air supply assembly housing (120) and a solenoid valve, a powder storage chamber (118) and a drive air storage chamber (119) arranged in the air supply assembly housing (120); the base housing (113) is fixedly mounted on the outer wall of the air supply assembly housing (120); the compressed air outlet of the air compressor (5) is connected in parallel with the powder storage chamber (118) and the drive air storage chamber (119) through an air pipe; a solenoid valve is arranged on one side of the air inlet pipe of the powder storage chamber (118); A first solenoid valve (114) is installed, one side of the air outlet pipe of the powder storage chamber (118) is connected to the dispersion nozzle (108), and a second solenoid valve (115) is installed on one side of the air outlet pipe of the powder storage chamber (118); a third solenoid valve (116) is installed on one side of the air inlet pipe of the driving air storage chamber (119), one side of the air outlet pipe of the driving air storage chamber (119) is connected to the pneumatic electrode (105), and a fourth solenoid valve (117) is installed on one side of the air outlet pipe of the driving air storage chamber (119).

2. A dust explosion flame free radical testing system according to claim 1, characterized in that: The optical observation assembly (2) comprises a narrowband filter (201) and a high-speed CCD camera (202). The narrowband filter (201) is mounted on the front side of a lens of the high-speed CCD camera (202). The high-speed CCD camera (202) is electrically connected to a control system (3) and a computer (4) via data cables.

3. A dust explosion flame free radical testing system according to claim 2, characterized in that: The narrowband filter (201) has a passband of 10 nm, and the central wavelength is determined according to the observed free radicals.

4. A dust explosion flame free radical testing system according to claim 1, characterized in that: The control system (3) comprises a PLC module, a power supply module, a high-voltage power supply module, a grounding module and a communication module integrated in a control box.

5. A method for conducting a dust explosion flame free radical test using the test system according to claim 1, characterized in that: The following steps are involved: S1. Installation and inspection of the test device: selecting a narrowband filter (201) of a corresponding wavelength according to the free radical to be observed, and then assembling the experimental device, installing the gas supply line and the control line, and installing and debugging the overall test system; S2. Laying combustible dust: First, the electric control gear (112) controls the first curved transparent plate (102) and the second curved transparent plate (103) to slide into the corresponding first chute and second chute respectively through the sliding connecting rod (110) and the transmission module (111), and the opening is in an open state; then, a certain amount of combustible dust is weighed and the combustible dust is evenly spread on the bottom of the powder holding chamber (109); finally, the sliding connecting rod (110) and the transmission module (111) control the first curved transparent plate (102) and the second curved transparent plate (103) to reset, and the opening is in a closed state; S3, charging: the control system (3) controls the first solenoid valve (114) and the third solenoid valve (116) to be in an open state, and the air compressor (5) charges compressed air into the powder spraying air storage chamber (118) and the driving air storage chamber (119), respectively. When the air pressure in the powder spraying air storage chamber (118) and the driving air storage chamber (119) reaches a predetermined value, the first solenoid valve (114) and the third solenoid valve (116) are closed; S4, forming a single-sided open dust cloud: the control system (3) controls the second solenoid valve (115) to open, and the high-pressure compressed air in the powder storage chamber (118) is ejected from the dispersion nozzle (108), blowing up the combustible dust contained in the powder chamber (109), forming a dust cloud that diffuses upward; at the same time, the electric control gear (112) controls the first curved transparent plate (102) and the second curved transparent plate (103) to slide into the corresponding first chute and second chute again through the sliding connecting rod (110) and the transmission module (111), and the opening is in the open state again, and at this time a single-sided open dust cloud is formed in the sleeve (1); S5, electrostatic ignition: the control system (3) controls the fourth solenoid valve (117) to open, and at the same time moves the pneumatic electrode (105) in the sleeve (1) closer to the fixed electrode (106), breaking through the air to generate electrostatic sparks and ignite the dust cloud; S6. Data acquisition: The flame free radical data during the explosion process is collected through the optical observation component (2) and transmitted to the computer (4) for visual display and storage; S7. Cleaning the device: After returning the pneumatic electrode (105) to its original position, release the remaining static electricity in the capacitor, and then clean the residual dust and combustion products on the test device; after the experiment is completed, turn off the power, disassemble the device and clean each component to prepare for the next cycle.

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