Integrated Device for Laminar Flame Ignition and Soot Sampling in High-Pressure Chamber and Sampling Method

Abstract

The present invention discloses an integrated device for laminar flame ignition and soot collection in a high-pressure chamber and a sampling method, which relates to the technical field of soot collection. The device includes a high-pressure chamber, a laminar diffusion burner, an ignition mechanism, a soot collection mechanism and a control center. The laminar diffusion burner, the ignition mechanism and the soot collection mechanism are all arranged inside the high-pressure chamber. The control center is used to control the operation of the laminar diffusion burner, the ignition mechanism and the soot collection mechanism. The ignition mechanism is arranged on the inner wall of the high-pressure chamber and is used for igniting the laminar diffusion burner. The soot collection mechanism includes two transverse slide rails and multiple groups of collection components, and multiple groups of the collection components are arranged side by side on the two transverse slide rails. The present invention can continuously collect multiple samples under the same working conditions, realizing multiple samplings with a single opening of the chamber. This sampling method greatly reduces the number of times of opening and closing the high-pressure chamber, solves the sealing problem caused by frequent opening and closing of the high-pressure chamber, not only saves time, but also reduces experimental errors.

Description

Technical Field

[0001] The present invention relates to the technical field of soot collection, and particularly to an integrated device for laminar flame ignition and soot collection in a high-pressure cavity and a sampling method. Background Art

[0002] With the rapid economic development and the improvement of people's living standards, the per capita car ownership in China has increased rapidly, and the environmental problems caused by automobile exhaust emissions have become prominent. Soot particles are one of the main pollutants emitted by automobiles. Their formation is the result of incomplete combustion of fuel under heat decomposition conditions and is the main source of environmental suspended pollutants. At the same time, soot particles can also cause great damage to the human respiratory system, seriously affecting the environment and human health. Mastering the formation mechanism of soot is the best way to control and reduce soot emissions. However, current research on soot mainly focuses on the atmospheric pressure environment because it is easier to conduct research on soot under atmospheric pressure, and both non-contact detection and contact detection methods can be achieved with current detection means. In fact, most actual fuel usage scenarios are in a high-pressure environment. Therefore, research on soot in fuel combustion under high pressure is particularly important. Moreover, it is more difficult to detect flames under high pressure, and the soot detection technology in high-pressure equipment needs to be further improved.

[0003] For example, the authorized announcement number CN106442854B discloses a soot detection system and its detection method in a laminar flame of hydrocarbon fuel. In this patent, SiC fibers installed in the sampling mechanism are used to sample soot in the flame. The advantage of this solution is that it can collect soot particles at different heights and angles. However, this sampling method for soot is not suitable for high-pressure environments and has certain limitations.

[0004] Another example is the application publication number CN108760589A, which discloses a soot collection system and its particle size analysis method in a laminar flame of soot fuel. In this application, a self-locking tweezer at the front end of a thermophoretic probe is used to clamp a copper mesh and quickly enter and exit the flame to complete the collection of soot in the flame. This solution uses a traditional cylinder to control the collection device. The innovation lies in that the time can be accurately controlled within milliseconds during soot collection, so as to realize soot collection during the formation process of soot and provide a basis for the study of the growth mechanism. However, in this application, the thermophoretic probe can only clamp one copper mesh each time. After one sampling, the steps of replacing the copper mesh are complex and time-consuming. Secondly, this system can only collect soot at the center position of the flame, and it is difficult to fully observe the entire soot generation situation at the same height.

[0005] In summary, current research on soot is carried out in the atmospheric pressure environment and cannot be carried out in the high-pressure environment. At the same time, only one soot collection can be performed in one experiment. When multiple sets of data are required, multiple experiments need to be carried out, resulting in low efficiency and large experimental errors.

[0006] In view of the above defects, the inventors of the present invention have finally obtained the present invention through long-term research and practice. Summary of the Invention

[0007] The purpose of the present invention is to provide an integrated device and sampling method for laminar flame ignition and soot collection in a high-pressure chamber, which solves the problems that current research cannot be carried out under high-pressure environments and multiple soot collections cannot be performed.

[0008] The present invention solves the above technical problems through the following technical solutions. The present invention includes a high-pressure chamber, a laminar diffusion burner, an ignition mechanism, a soot collection mechanism, and a control center. The laminar diffusion burner, the ignition mechanism, and the soot collection mechanism are all arranged inside the high-pressure chamber, and the control center is used to control the operation of the laminar diffusion burner, the ignition mechanism, and the soot collection mechanism.

[0009] The ignition mechanism is arranged on the inner wall of the high-pressure chamber and is used for igniting the laminar diffusion burner.

[0010] The soot collection mechanism includes two horizontal slide rails and multiple groups of collection components. The multiple groups of collection components are arranged in parallel on the two horizontal slide rails, and the control center controls the multiple collection components to move along the horizontal slide rails in sequence to perform soot sampling on the flame of the laminar diffusion burner.

[0011] Preferably, the collection component includes two horizontally self-moving sliders and a sampling wire; the two horizontally self-moving sliders are respectively slidably installed on the two horizontal slide rails, and the two ends of the sampling wire are respectively adhered to the two horizontally self-moving sliders.

[0012] Preferably, the positions where the two horizontally self-moving sliders adhere to the sampling wire are both marked, and the marks are located in the middle of the horizontally self-moving sliders.

[0013] Preferably, the sampling wire is made of silicon carbide.

[0014] Preferably, the two horizontal slide rails have a synchronous vertical movement function. Two pairs of symmetrically arranged vertical slide rails are fixed on the inner wall of the high-pressure chamber, vertical self-moving sliders are installed on both pairs of vertical slide rails, and the two ends of the two horizontal slide rails are respectively fixed to the corresponding vertical self-moving sliders.

[0015] Preferably, a scale for quantifying the lifting height of the horizontal slide rail is engraved on the inner wall of the high-pressure chamber.

[0016] Preferably, the ignition mechanism includes a pneumatic telescopic rod and an ignition needle. The pneumatic telescopic rod is fixed on the inner wall of the high-pressure chamber, and the ignition needle is installed at the telescopic end of the pneumatic telescopic rod.

[0017] Preferably, a signal receiving unit is provided for the laminar diffusion burner, the ignition mechanism and the soot collection mechanism. The signal receiving unit is used to receive the action instructions sent by the control center. A power control unit is arranged in the high-pressure chamber, and the power control unit supplies power to the laminar diffusion burner, the ignition mechanism and the soot collection mechanism.

[0018] The present invention also proposes a method for sampling soot in a laminar flame in a high-pressure chamber. According to the above-mentioned integrated device for ignition and soot collection of a laminar flame in a high-pressure chamber, the soot sampling work is carried out, including the following steps:

[0019] S1: Open the high-pressure chamber, move all the collection parts inside the chamber to one side, and at the same time adjust the height of the vertically self-moving slider so that the sampling wire of the collection part is at the same height as the flame center, and then close the high-pressure chamber;

[0020] S2: Introduce fuel gas and air into the pipeline below the laminar diffusion burner in the high-pressure chamber, and pay attention to the pressure change and airtightness inside the high-pressure chamber. When there is no abnormality in the high-pressure chamber cavity, ignition can be started;

[0021] S3: Control the pneumatic telescopic rod to extend so that the ignition needle stops at the burner nozzle of the laminar diffusion burner, connect the DC power supply, heat the heating wire inside the ignition needle to the set temperature to ignite the mixed gas. After ignition, when the ignition in the high-pressure chamber is successful, the pneumatic telescopic rod will contract, and the ignition mechanism will return to the initial contracted stage and will not interfere with the flame combustion;

[0022] S4: When the flame is stable, start sampling. Use the control center to control the two horizontally self-moving sliders of the collection part closest to the laminar diffusion burner to move synchronously, so that the sampling wire of the collection part moves to the flame center position for sampling. When the sampling time ends, the program will automatically control the horizontally self-moving slider to move to the other end of the horizontal slide rail;

[0023] S5: Repeat the operation of S4. Multiple collection parts respectively collect soot from the flame. During each collection, the positions of the horizontally self-moving slider and the vertically self-moving slider can be adjusted to achieve sampling at different heights and positions of the flame. After the collection is completed, turn off the laminar diffusion burner, relieve the pressure and then open the high-pressure chamber, and remove the sampling wire with the collected sample.

[0024] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0025] 1. It can continuously collect multiple samples under the same working conditions, realizing multiple samplings with a single cavity opening. This sampling method greatly reduces the number of times of opening and closing the high-pressure chamber, solves the sealing problem caused by frequent opening and closing of the high-pressure chamber, not only saves time and improves efficiency, but also reduces experimental errors;

[0026] 2. The present invention innovatively adopts a module that can move up and down, enabling the collection of soot at different heights of the flame.

[0027] 3. While realizing automatic sampling, the present invention can also simultaneously achieve an automatic ignition function, greatly improving the efficiency of the experiment. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic structural diagram of an integrated device for laminar flame ignition and soot collection in a high-pressure cavity;

[0029] Figure 2 is Figure 1 a sectional view of the laminar diffusion burner in the high-pressure cavity in

[0030] Figure 3 is Figure 2 a schematic structural diagram of the collection mechanism and the ignition device in

[0031] Figure 4 is Figure 2 a schematic structural diagram of the ignition mechanism in the ignition state in

[0032] The numbers in the figures represent:

[0033] 100 - high-pressure cavity; 210 - vertical slide rail; 220 - vertical self-moving slider; 230 - horizontal slide rail; 240 - horizontal self-moving slider; 250 - sampling wire; 300 - laminar diffusion burner; 310 - pneumatic telescopic rod; 320 - ignition needle; 400 - power control unit. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0034] The following further elaborates on the above and other technical features and advantages of the present invention with reference to the accompanying drawings.

[0035] Embodiment 1

[0036] This embodiment provides a technical solution: an integrated device for laminar flame ignition and soot collection in a high-pressure cavity. Referring to Figures 1-4 , it includes a high-pressure cavity 100, which is made of 316 stainless steel. A laminar diffusion burner 300 is installed inside. Four flanges are provided at the same height of the burner for observing the flame condition. The entire interior of the high-pressure cavity is completely sealed and can achieve a pressure increase of 50 atm through testing. After sealing the high-pressure cavity, the interior of the cavity can be pressurized to make the cavity environment a high-pressure state. The experiments of this solution are also carried out in a high-pressure environment;

[0037] An ignition mechanism and a soot collection mechanism are also provided inside the high-pressure chamber 100. The ignition mechanism is arranged on the inner wall of the high-pressure chamber 100 and is used for igniting the laminar diffusion burner 300. The ignition mechanism is composed of an ignition needle 320 and a telescopic rod 310. The telescopic rod is pneumatically actuated and can extend during use and retract into the inner wall of the chamber when not needed. The ignition principle of the ignition needle is that the heating wire heats up after being energized to complete ignition.

[0038] The soot collection mechanism can perform soot sampling operations on the laminar diffusion burner 300 multiple times. A control center is also provided outside, which is used to control the operation of the laminar diffusion burner 300, the ignition mechanism and the soot collection mechanism to achieve automatic control. The laminar diffusion burner 300, the ignition mechanism and the soot collection mechanism are provided with signal receiving units, which are used to receive the action instructions issued by the control center. In addition, a power control unit 400 is provided inside the high-pressure chamber 100, and the power control unit 400 supplies power to the laminar diffusion burner 300, the ignition mechanism and the soot collection mechanism.

[0039] The soot collection mechanism includes two horizontal slide rails 230 and multiple groups of collection components. The two horizontal slide rails 230 are installed on the inner wall of the high-pressure chamber 100, and the two horizontal slide rails 230 are arranged in parallel. Multiple groups of collection components are arranged in parallel and slidably on the two horizontal slide rails 230. The collection component includes two horizontally self-moving sliders 240 and a sampling wire 250. The two horizontally self-moving sliders 240 are respectively slidably installed on the two horizontal slide rails 230.

[0040] The two horizontally self-moving sliders 240 can move on the horizontal slide rails 230. The moving mode of the horizontally self-moving sliders 240 is realized by a gear and rack matching drive. Specifically, a rack is installed above the horizontal slide rail 24, and a rotatable gear is installed on the horizontally moving horizontally self-moving slider 240. The gear is meshed with the rack, and the motor drives the rack to rotate, thereby driving the slider to move.

[0041] The sampling wire 250 is installed on the corresponding two horizontally self-moving sliders 240 in a fixed tape fixing manner. The installation position of the sampling wire is in the exact middle of the slider. Mark the exact middle position of the slider to facilitate placing the sampling wire in the exact middle.

[0042] The component of the sampling wire 250 is SiC fiber wire. SiC fiber wire has the advantages of high temperature resistance and little influence on the flame, etc. It is a very effective sampling method for soot research and can complete the collection of samples in the flame with little influence on the flame.

[0043] During use, the control center controls a plurality of laterally self - moving sliders 240 with sampling filaments 250 to move along the lateral slide rail 230 in sequence. Sampling starts when the position of the sampling filament 250 is in the exact middle of the flame in the laminar diffusion burner 300. After one sampling is completed, the slider slides to another section to collect the next sample, thus completing the sampling of soot in the flame multiple times.

[0044] After the ignition process is completed and the flame stabilizes, sampling of the sampling filament 250 can begin. First, the laterally self - moving slider 240 can receive commands from the control center to achieve precise movement. During the sampling process of the sampling filament 250, first, a signal is sent by the control center. The laterally self - moving slider 240 is controlled by the control center. After receiving the signal from the control center, the laterally self - moving slider 240 starts to move from the other end and gradually moves to the exact center of the flame. At this time, the sampling filament 250 needs to be at the exact center of the flame. If it is not at the exact center of the flame, the position of the laterally self - moving slider 240 controlled by the control center can be adjusted until the sampling filament 250 is at the exact center of the flame. After setting the sampling time, when the sampling is completed, the control center emits an end command. At this time, the laterally self - moving slider 240 moves from the sampling position to the other end, completing one sampling. In fact, each working condition often requires a different number of samples. Therefore, when conducting the next sampling, it is also carried out in this way to achieve the purpose of experimental sampling, enabling continuous collection of multiple samples under one working condition, and allowing the high - pressure chamber 100 to be opened to take out the samples after all working conditions are completed. This sampling method can greatly reduce the number of times the high - pressure chamber 100 is opened and closed, saving time, improving efficiency, and reducing experimental errors at the same time.

[0045] The sampling system of this embodiment can, on the one hand, achieve multiple samplings, and on the other hand, does not require opening the high - pressure chamber 100, reducing the impact brought by the interruption of the experiment. When one sampling is completed, we can quickly conduct the second sampling. The interval time in the middle is relatively short, bringing smaller errors, improving the accuracy of the experiment, and saving sampling time. The design of the lateral slide rail 230 can well optimize the space inside the cavity and reduce the impact brought by the gas flow in the cavity.

[0046] Embodiment Two

[0047] This embodiment is further optimized on the basis of the above - mentioned embodiment. The same parts as the previous technical solutions will not be elaborated here, such as Figures 2-3As shown in the figure, to better implement the present invention, the following setting method is particularly adopted: the two horizontal slide rails 230 have the function of synchronous vertical movement, so as to adjust the height of the acquisition component. Two pairs of symmetrically arranged vertical slide rails 210 are fixed on the inner wall of the high-pressure chamber 100. Vertical self-moving sliders 220 are installed on both pairs of vertical slide rails 210. The moving mode of the vertical self-moving sliders 220 is the same as that of the horizontal self-moving sliders 240, and will not be elaborated here too much. The two ends of the two horizontal slide rails 230 are respectively fixed to the corresponding vertical self-moving sliders 220. Both pairs of vertical self-moving sliders 220 are controlled by the control center to operate, and can move synchronously on the vertical slide rails 210, so as to realize the adjustment of the height of the acquisition component, realize the sampling at different heights of the flame, and improve the applicability. In order to accurately adjust the height of the sampling wire 250, a scale for quantifying the lifting height of the horizontal slide rail 230 is engraved on the inner wall of the high-pressure chamber 100. According to the scale, the sampling wire 250 can be accurately adjusted to the appropriate height.

[0048] Embodiment III

[0049] This embodiment is further optimized on the basis of Embodiment I. The same parts as the foregoing technical solutions will not be elaborated here. As Figures 2-4 shown in the figure, to better implement the present invention, the following setting method is particularly adopted: the ignition mechanism includes a pneumatic telescopic rod 310 and an ignition needle 320. The pneumatic telescopic rod 310 is fixed to the inner wall of the high-pressure chamber 100, and the ignition needle 320 is installed at the telescopic end of the pneumatic telescopic rod 310.

[0050] The ignition mechanism inside the cavity of the present invention is an electric heating wire ignition mechanism located inside the high-pressure chamber 100, which can realize remote control of ignition inside the cavity. The cylinder telescopic rod is used in cooperation. The pneumatic telescopic rod 310 can realize remote control of telescoping. The ignition needle 320 is installed at the telescopic end of the pneumatic telescopic rod 310 to realize the self-movement of the ignition needle 320. When ignition is required in the experiment, the pneumatic telescopic rod 310 can be extended to make the ignition needle 320 close to the ignition point of the burner. After ignition, the pneumatic telescopic rod 310 and the ignition needle 320 can be retracted to the edge of the cavity, which can greatly reduce the influence on the flame combustion environment.

[0051] The process of igniting the flame inside the traditional high-pressure chamber 100 of ignition is: opening the cavity for ignition, and then closing the cavity after the flame is ignited. This method is not only unsafe, but also the flame is very easy to go out during the pressure increase process. The secondary ignition after going out is very troublesome. It is necessary to reduce the pressure of the high-pressure chamber 100, then open the ignition port, and then introduce gas to re-ignite. This working method is very inefficient. Therefore, designing this way of igniting inside the cavity can greatly improve the efficiency of the experiment.

[0052] Example 4

[0053] This embodiment provides a technical solution: a method for sampling soot from a laminar flame in a high-pressure chamber. The soot sampling work is carried out according to the integrated device for laminar flame ignition and soot collection in the high-pressure chamber 100 of the above embodiment. Refer to Figures 1-4 , including the following steps:

[0054] S1: Open the high-pressure chamber 100, use tape to bond the sampling wire 250 to the two horizontal self-moving sliders 240 of the collecting piece, then move all the collecting pieces inside the chamber to one side, and at the same time adjust the height of the vertical self-moving slider 220 so that the sampling wire 250 of the collecting piece is at the same height as the flame center to ensure that the sampling wire 250 can smoothly collect soot. Finally, close the high-pressure chamber 100;

[0055] S2: Pass fuel gas and air into the pipeline below the laminar diffusion burner 300 in the high-pressure chamber 100, and pay attention to the pressure change and airtightness inside the high-pressure chamber. When there is no abnormality in the high-pressure chamber body, ignition can be started;

[0056] S3: Control the pneumatic telescopic rod 310 to extend so that the ignition needle 320 stops at the burner nozzle of the laminar diffusion burner 300, connect the DC power supply, heat the heating wire inside the ignition needle 320 to the set temperature to ignite the mixture gas. After ignition, when the ignition is successful inside the high-pressure chamber 100, the pneumatic telescopic rod 310 will contract, and the ignition mechanism will return to the initial contracted stage without interfering with the flame combustion;

[0057] S4: When the flame is stable, start sampling. Use the control center to control the two horizontal self-moving sliders 240 of the collecting piece closest to the laminar diffusion burner 300 to move synchronously, so that the sampling wire 250 of the collecting piece moves to the flame center position. The sampling wire 250 is left stationary in the flame for a certain time to complete the sampling. The soot particles in the flame will deposit on the sampling wire 250 to complete the sampling, and the program will automatically control the horizontal self-moving slider 240 to move to the other end of the horizontal slide rail 230;

[0058] S5: Repeatedly cycle the operation of S4. Multiple collecting pieces respectively collect soot from the flame. During each collection, by adjusting the positions of the horizontal self-moving slider 240 and the vertical self-moving slider 220, sampling at different heights and positions of the flame can be achieved. After the collection is completed, extinguish the flame, relieve the pressure, and then open the high-pressure chamber 100 to remove the sampling wire 250 with the collected sample.

[0059] The above are only the preferred embodiments of the present invention, which are illustrative rather than restrictive to the present invention. Those skilled in the art understand that many changes, modifications, or even equivalents can be made within the spirit and scope defined by the claims of the present invention, but all of them will fall within the protection scope of the present invention.

Claims

1. An integrated device for laminar flame ignition and soot collection in a high-pressure chamber, Characterized in that: It includes a high-pressure chamber, a laminar diffusion burner, an ignition mechanism, a soot collection mechanism and a control center. The laminar diffusion burner, the ignition mechanism and the soot collection mechanism are all arranged inside the high-pressure chamber, and the control center is used to control the operation of the laminar diffusion burner, the ignition mechanism and the soot collection mechanism; The ignition mechanism is arranged on the inner wall of the high-pressure chamber and is used for igniting the laminar diffusion burner; The soot collection mechanism includes two transverse slide rails and multiple groups of collection components. Multiple groups of the collection components are arranged side by side on the two transverse slide rails, and the control center controls the multiple collection components to move along the transverse slide rails in sequence to perform soot sampling on the flame of the laminar diffusion burner.

2. The integrated device for laminar flame ignition and soot collection in a high-pressure chamber according to claim 1, Characterized in that, The collection component includes two laterally self-moving sliders and a sampling wire; the two laterally self-moving sliders are respectively slidably installed on the two transverse slide rails, and both ends of the sampling wire are adhered to the two laterally self-moving sliders.

3. The integrated device for laminar flame ignition and soot collection in a high-pressure chamber according to claim 2, Characterized in that, Both positions where the two laterally self-moving sliders adhere to the sampling wire have marks, and the marks are located in the middle of the laterally self-moving sliders.

4. The integrated device for laminar flame ignition and soot collection in a high-pressure chamber according to claim 2, Characterized in that, The sampling wire is made of silicon carbide.

5. The integrated device for laminar flame ignition and soot collection in a high-pressure chamber according to claim 1, Characterized in that, The two transverse slide rails have a synchronous vertical movement function. Two pairs of symmetrically arranged vertical slide rails are fixed on the inner wall of the high-pressure chamber. Vertical self-moving sliders are installed on both pairs of vertical slide rails, and both ends of the two transverse slide rails are respectively fixed to the corresponding vertical self-moving sliders.

6. The integrated device for laminar flame ignition and soot collection in a high-pressure chamber according to claim 5, Characterized in that, A scale for quantifying the lifting height of the transverse slide rail is engraved on the inner wall of the high-pressure chamber.

7. The integrated device for laminar flame ignition and soot collection in a high-pressure chamber according to claim 1, Characterized in that, The ignition mechanism includes a pneumatic telescopic rod and an ignition needle. The pneumatic telescopic rod is fixed on the inner wall of the high-pressure chamber, and the ignition needle is installed at the telescopic end of the pneumatic telescopic rod.

8. The integrated device for laminar flame ignition and soot collection in a high-pressure chamber according to claim 1, Characterized in that, The laminar diffusion burner, the ignition mechanism and the soot collection mechanism are provided with a signal receiving unit. The signal receiving unit is used to receive the action instructions issued by the control center. A power control unit is arranged inside the high-pressure chamber, and the power control unit provides power for the laminar diffusion burner, the ignition mechanism and the soot collection mechanism.

9. A method for sampling laminar flame soot in a high-pressure chamber, which performs soot sampling work according to the integrated device for laminar flame ignition and soot collection in a high-pressure chamber according to any one of claims 1-8, Characterized in that, It includes the following steps: S1: Open the high-pressure chamber, move all the acquisition components inside the chamber to one side, and at the same time adjust the height of the vertically self-moving slider so that the sampling wire of the acquisition component is at the same height as the flame center, then close the high-pressure chamber; S2: Introduce fuel gas and air into the pipeline below the laminar diffusion burner in the high-pressure chamber, and pay attention to the pressure change and airtightness inside the high-pressure chamber. When there is no abnormality in the high-pressure chamber body, ignition can be started; S3: Control the pneumatic telescopic rod to extend so that the ignition needle stops at the burner nozzle of the laminar diffusion burner, connect the DC power supply, heat the heating wire inside the ignition needle to the set temperature to ignite the mixture. After ignition, when the ignition is successful inside the high-pressure chamber, the pneumatic telescopic rod will contract, and the ignition mechanism will return to the initial contracted stage without interfering with the flame combustion; S4: After the flame stabilizes, start sampling. Use the control center to control the two horizontally self-moving sliders closest to the acquisition component of the laminar diffusion burner to move synchronously, so that the sampling wire of the acquisition component moves to the flame center position for sampling. When the sampling time ends, the program will automatically control the horizontally self-moving slider to move to the other end of the horizontal slide rail; S5: Repeat the operation of S4. Multiple acquisition components respectively collect soot from the flame. During each collection, by adjusting the positions of the horizontally self-moving slider and the vertically self-moving slider, sampling at different heights and positions of the flame can be achieved. After the collection is completed, extinguish the laminar diffusion burner, relieve the pressure and then open the high-pressure chamber, and remove the sampling wire with the collected sample.

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