A high-temperature, high-pressure micro-combustion device and method for single-particle fuel

Abstract

This invention relates to a high-temperature, high-pressure micro-combustion device and method for single-particle fuel. The invention comprises a heat-insulating cavity between the combustion chamber body, the heat-insulating shell, and the heat-insulating top plate, sealed with an optical glass window on both sides of the combustion chamber in the middle of the combustion chamber body. An air inlet and an air outlet for the combustion chamber are located within the combustion chamber body. A glass gasket is nested in the middle of the combustion chamber body, and a micro-combustion plate is placed on the glass gasket. A ring-shaped cast copper heating plate surrounds the combustion chamber on the outer side opposite the glass gasket. A high-speed camera, a high-magnification objective lens, and a background light source are located outside the optical glass window. A laser emitted from a laser enters the high-temperature, high-pressure combustion chamber perpendicularly. This invention can more efficiently and easily meet the requirements of high-temperature, high-pressure micro-combustion experiments under a microscope. It is simple to manufacture, highly stable, heat-insulating, and can flexibly address imaging problems in microparticle ignition and combustion experiments, effectively conducting interference-free testing of single-particle micro-combustion under high-temperature, high-pressure conditions.

Description

Technical Field

[0001] This invention belongs to the field of micro-combustion experimental technology and relates to a high-temperature and high-pressure single-particle fuel micro-combustion device and method. Background Technology

[0002] Microparticle fuels have been widely used in various fields such as aerospace, power electronics, and pyrotechnics. Because the combustion of microparticle fuels involves complex chemical reactions, multiphase flow, and heat and mass transfer processes, a deeper understanding of their ignition and combustion mechanisms and an assessment of their combustion characteristics (such as ignition energy threshold, ignition delay time, combustion time, emission spectrum, and radiation temperature) requires not only macroscopic studies of interparticle interactions within particle stacks but also microscopic investigations of the combustion process of individual particles. Therefore, further experimental research on the ignition and combustion characteristics of single microparticle fuels is of paramount scientific significance for revealing their complex ignition and combustion mechanisms.

[0003] However, since the particle size of individual microparticles is mostly in the micrometer or even nanometer range, imaging and ignition must be performed under a high-powered microscope, and the combustion environment must be controlled accordingly. Therefore, there are many limitations in the ignition and combustion experiments, which brings many challenges to the design of the combustion chamber. First, combustion at the microscale requires a large space for the combustion chamber, which limits the experimental modes of the combustion chamber and greatly increases the difficulty of experimental operations under some special conditions, such as high temperature and high pressure. Second, due to the scale characteristics of micro-combustion, the imaging of its combustion process is limited by the working distance of the microscope objective. To achieve combustion under high pressure conditions, it is necessary to increase the thickness of the optical observation window lens. However, increasing the thickness of the optical observation window will affect the imaging of the microscope objective. The relationship between these two constraints has become a key problem that needs to be overcome in the design of the combustion chamber structure.

[0004] In summary, balancing the introduction of special operating conditions such as high temperature and high pressure with clear imaging and experimental stability of the ignition and combustion process presents a significant challenge for experimental technicians. Therefore, developing a micro-combustion experimental device for single-particle fuel under high temperature and high pressure conditions and its application method has excellent scientific significance and engineering practicality in combustion testing, diagnosis, and experimentation. Summary of the Invention

[0005] The purpose of this invention is to provide a high-temperature, high-pressure single-particle fuel micro-combustion device and method.

[0006] To solve the above technical problems, the technical solution adopted by the present invention is as follows:

[0007] A high-temperature and high-pressure single-particle fuel micro-combustion device includes a high-temperature and high-pressure combustion chamber, a high-speed camera, a laser, a high-magnification objective lens, and a background light source.

[0008] The high-temperature and high-pressure combustion chamber includes a heat-insulating shell, a heat-insulating top plate, a combustion chamber body, and a cover, with the cover fixed to the side wall of the combustion chamber body;

[0009] The heat insulation shell is a barrel-shaped structure with one side opening. The combustion chamber body and the cover are placed inside the heat insulation shell. A column is set at the bottom of the heat insulation shell to support the combustion chamber body. A heat insulation top plate is set on the open side of the heat insulation shell. A heat insulation cavity is set between the combustion chamber body and the heat insulation shell and the heat insulation top plate, and heat insulation is achieved by air.

[0010] The combustion chamber is located in the middle of the main body of the combustion chamber; the cover is milled with a mirror groove with the same shape as the optical lens, which is used to install the optical lens and restrict its movement to form an optical glass window; the combustion chamber has openings on opposite sides that are respectively opposite to the first optical glass window and the second optical glass window; sealing gaskets are provided between the first optical glass window, the second optical glass window and the combustion chamber.

[0011] The heat-insulating outer shell and heat-insulating top plate have openings at positions relative to the first and second optical glass windows to facilitate light transmission, observation, and photography.

[0012] The combustion chamber body has a combustion chamber air inlet and a combustion chamber air outlet. The combustion chamber air inlet and the combustion chamber air outlet are connected by a slot in the combustion chamber body. The combustion chamber air inlet fills and pressurizes the sealed space formed by the combustion chamber and the optical glass window through the combustion chamber air inlet; the combustion chamber air outlet exhausts and releases pressure.

[0013] A groove is provided in the middle of the combustion chamber body to house and restrict the movement of a glass gasket. Micro-burning discs are placed on the glass gaskets, and individual particulate fuel particles are placed on the micro-burning discs during combustion. An annular cast copper heating plate surrounds the combustion chamber relative to the outside of the glass gaskets.

[0014] A high-speed camera and a high-magnification objective lens are installed outside the first optical glass window for photography and imaging, while a background light source is installed outside the second optical glass window.

[0015] The axes of the high-speed camera and high-magnification objective lens are collinear with the geometric centers of the first and second optical glass windows, as well as with the single particulate fuel and the background light source. The laser emitted by the laser enters the high-temperature and high-pressure combustion chamber perpendicularly through the total reflection mirror, color mirror, high-magnification objective lens, and the first optical glass window.

[0016] The ring-shaped cast copper heating plate is controlled and its heating temperature is monitored by an external temperature control box.

[0017] The combustion chamber body and cover are made of aluminum alloy.

[0018] A mass flow controller is connected to the air inlet of the combustion chamber via a pipeline; a safety valve is also installed on the air inlet pipeline of the mass flow controller.

[0019] The mass flow controller's outlet is connected to the combustion chamber's inlet via a pipeline. The mass flow controller's inlet is connected to the buffer tank's outlet via a pipeline, and a solenoid valve is installed on the mass flow controller's inlet pipeline. The buffer tank's inlet is connected to the gas cylinder's outlet via a pipeline, and a pressure reducing valve is installed on the buffer tank's inlet pipeline.

[0020] One branch of the combustion chamber outlet is connected in series with a solenoid valve and a pressure reducing valve via a pipeline. The other branch of the combustion chamber outlet is connected to a pressure gauge via a pipeline, and the pressure gauge outlet is connected to a vacuum pump via a pipeline. A solenoid valve is installed on the pressure gauge outlet pipeline.

[0021] The optical glass window is made of quartz glass.

[0022] The high-speed camera is equipped with a filter.

[0023] A method for micro-combustion of single-particle fuel under high temperature and high pressure specifically includes the following steps:

[0024] The first step is selecting the optical observation window:

[0025] Based on the selected window shape and the set maximum pressure, the required standard thickness of the window glass is calculated according to the pressure and the standard thickness formula of the optical glass window.

[0026] The second step is selecting the glass gasket:

[0027] Based on the imaging conditions in the experiment, the required thickness of the glass gasket is calculated;

[0028] Step 3, sample injection:

[0029] The micro fuel is placed on the micro-combustion plate, and then the cap and the heat insulation plate are tightened in sequence.

[0030] Step 4: Generation of a high-temperature, high-pressure combustion environment:

[0031] The annular cast copper heating plate is powered on, which heats the annular cast copper heating plate to create a high temperature in the combustion chamber. The heating temperature of the annular cast copper heating plate is controlled by a temperature control box. Gas is then injected into the combustion chamber through the combustion chamber air inlet to create a high pressure in the combustion chamber. The pressure holding status is monitored by a pressure gauge.

[0032] Step 5, ignition and combustion: igniting and burning individual microparticle fuels using laser ignition;

[0033] The sixth step is to depressurize the combustion chamber through the exhaust port and cool the combustion chamber cavity.

[0034] To address the problems of existing technologies, this invention can more efficiently and easily meet the requirements of high-temperature and high-pressure micro-combustion experimental environment under a microscope. It is simple to process and manufacture, has strong stability, is heat-insulated, and can more flexibly address imaging problems in microparticle ignition and combustion experiments. It can effectively conduct non-interference testing of single-particle micro-combustion under high-temperature and high-pressure environment, and better reveal its mechanism. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the overall structure of the device of the present invention;

[0036] Figure 2 for Figure 1 Schematic diagram of the external structure of the combustion chamber;

[0037] Figure 3 for Figure 1 A schematic diagram of the combustion chamber without the heat insulation shell and heat insulation top plate;

[0038] Figure 4 for Figure 1 Cross-sectional view of the overall structure of the combustion chamber;

[0039] Figure 5 This is a diagram illustrating the combustion process of a single particle in this invention. Detailed Implementation

[0040] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0041] like Figure 1 As shown, a high-temperature and high-pressure single-particle fuel micro-combustion device includes a high-temperature and high-pressure combustion chamber 1, a high-speed camera 22, a filter 23, a dichroic mirror 24, a first-stage total reflection mirror 25, a second-stage total reflection mirror 26, a laser 27, a high-magnification objective lens 28, and a background light source 36.

[0042] like Figures 2-3 As shown, the high-temperature and high-pressure combustion chamber 1 includes a heat-insulating shell 11, a heat-insulating top plate 12, a combustion chamber body 2, an upper cover 3 and a lower cover 4. The upper cover 3 and the lower cover 4 are fixed to opposite sides of the combustion chamber body 2 by flat-head bolts 19.

[0043] like Figure 4 As shown, the heat insulation shell 11 is a barrel-shaped structure with an opening on one side. The combustion chamber body 2, the upper cover 3, and the lower cover 4 are placed inside the heat insulation shell 11. The bottom of the heat insulation shell 11 is evenly provided with columns 21. In this embodiment, four columns are provided to support the combustion chamber body 2. The heat insulation shell 11 is fixedly connected to the heat insulation top plate 12 on the open side by hexagonal bolts 20. A heat insulation cavity 13 is provided between the combustion chamber body 2 and the heat insulation shell 11 and the heat insulation top plate 12, which is insulated by air.

[0044] A combustion chamber 9 is located in the middle of the combustion chamber body 2. Both the upper cover 3 and the lower cover 4 are milled with grooves identical in shape to optical lenses, used to install the optical lenses and restrict their movement, thus forming the upper optical glass window 5 and the lower optical glass window 7. Openings are provided on opposite sides of the combustion chamber 9, respectively, opposite the first optical glass window 5 and the second optical glass window 7. Sealing gaskets are used between the upper and lower optical glass windows 5 and the combustion chamber to ensure tight contact and meet sealing requirements. The first optical glass window 5 is sealed to one side of the combustion chamber 9 by the first sealing gasket 6 and the upper cover 3, and the second optical glass window 7 is sealed to the opposite side of the first optical glass window 5 by the second sealing gasket 8 and the lower cover 4.

[0045] Holes are provided in the heat-insulating outer shell 11 and the heat-insulating top plate 12 at positions relative to the first optical glass window 5 and the second optical glass window 7 to facilitate light transmission, observation, and photography.

[0046] The combustion chamber body 2 has a combustion chamber air inlet 17 and a combustion chamber air outlet 18 leading to the combustion chamber 9. The combustion chamber air inlet 17 and the combustion chamber air outlet 18 are connected by a slot in the combustion chamber body 2. The combustion chamber air inlet 17 fills and pressurizes the sealed space formed by the combustion chamber 9 and the optical glass window; the combustion chamber air outlet 18 exhausts and releases pressure.

[0047] A groove is provided in the middle of the combustion chamber body 2 to house the glass gasket 14 and restrict its movement. A micro-combustion piece 15 is placed on the glass gasket 14, and during combustion, individual particulate fuel 16 is placed on the micro-combustion piece 15. Glass gaskets 14 of different thicknesses can be selected according to imaging requirements. The glass gasket 14 is only used to house the micro-combustion piece 15 and does not separate the combustion chamber (a gap is left between the glass gasket 14 and the cross-section of the combustion chamber).

[0048] An annular cast copper heating plate 10 is also provided between the upper cover 3 and the combustion chamber body 2. The annular cast copper heating plate 10 surrounds the combustion chamber 9 on the outside of the glass gasket 14 and is used to heat the combustion environment of the individual particulate fuel 16.

[0049] The annular cast copper heating plate 10 achieves heating by electric heating, and the heating temperature is controlled and monitored by an external temperature control box 35.

[0050] In this embodiment, the combustion chamber body 2, the upper cover 3, and the lower cover 4 are made of aluminum alloy, which has high mechanical and process performance; the high temperature and high pressure combustion chamber 1 and the combustion chamber 9 are cylindrical or square in shape.

[0051] In this embodiment, a mass flow controller 31 is connected to the combustion chamber inlet 17 via a pipeline to control the mass and flow rate of the working gas, thereby improving the safety and stability of the experimental process. The working gas source is a gas cylinder 34. The outlet of the gas cylinder 34 is connected to the inlet of the buffer tank 33 via a pipeline, and a pressure reducing valve is installed on the inlet pipeline of the buffer tank 33. The outlet of the buffer tank 33 is connected to the inlet of the mass flow controller 31 via a pipeline, and a solenoid valve is installed on the inlet pipeline of the mass flow controller 31. The outlet of the mass flow controller 31 is connected to the combustion chamber inlet 17 via a pipeline. A safety valve 32 is also installed on the inlet pipeline of the mass flow controller 31.

[0052] The combustion chamber outlet 18 is connected in series with a solenoid valve and a pressure reducing valve via a pipeline.

[0053] A pressure gauge 29 is installed on the pipeline of the combustion chamber outlet 18 to monitor whether the pressure in the combustion chamber 9 reaches the set requirements. The outlet of the pressure gauge is connected to the vacuum pump 30 through a pipeline, and a solenoid valve is installed on the pipeline of the pressure gauge outlet.

[0054] A high-speed camera 22 and a high-magnification objective lens 28 are provided outside the first optical glass window 5 for photography and imaging. A background light source 36 is provided outside the second optical glass window 7. It should also be noted that, as a variation, the number of optical glass windows can be set to 2, 3, 4 or more depending on the experimental needs. The preferred material for the optical glass windows is quartz glass.

[0055] The axes of the high-speed camera 22 and the high-magnification objective lens 28 are on the same axis as the geometric center of the upper optical glass window 5, the second optical glass window 7, the single particle fuel 16, and the background light source 36.

[0056] A filter 23 is installed below the high-speed camera 22. A first-stage total reflection mirror 25 is positioned on the same horizontal line as the laser emitted by the laser 27. A second-stage total reflection mirror 26 is positioned on the same axis as the first-stage total reflection mirror 25. A dichroic mirror 24 is positioned on the same horizontal line as the second-stage total reflection mirror 26 and is on the same axis as the high-speed camera 22. The laser emitted by the laser 27 is reflected by the first-stage total reflection mirror 25, the second-stage total reflection mirror 26, and the dichroic mirror 24 and enters perpendicularly into the central axis of the high-magnification objective lens 28. It then passes through the first optical glass window 5 and enters the combustion chamber 9 of the high-temperature and high-pressure combustion chamber 1.

[0057] Based on the above device, the following method for micro-combustion of single-particle fuel is proposed:

[0058] The first step is selecting the optical observation window:

[0059] In this embodiment, the window shape is circular, and the maximum pressure p during the experiment is... maxThe maximum pressure of this device under high-pressure conditions is set to 3 MPa; then the pressure F exerted by the gas in the combustion chamber on the optical glass window is calculated using the following formula: Where A is the area of ​​the optical glass window and D is the diameter of the optical glass window.

[0060] Then, the required standard thickness of the optical glass window is calculated. In this embodiment, the selected optical glass window material is quartz glass JGS1, with a tensile strength limit of [τ] = 85 MPa, Poisson's ratio μ = 0.17, Young's modulus E = 72 GPa, and window diameter D = 16 mm. Let m = 1 / μ, then the calculation method for the standard thickness t of the optical glass window is as follows:

[0061] As described above, it can be calculated that in this embodiment, the pressure F exerted by the gas in the combustion chamber on the optical window is 602.88 N, and the standard thickness t of the optical glass window is 1.64 mm.

[0062] To ensure the safety and reliability of the experiment, the thickness of the optical glass window used in the experiment is generally greater than the calculated theoretical value. In this embodiment, the thickness of both the upper optical glass window 5 and the lower optical glass window 7 is 3mm.

[0063] The second step is selecting the glass gasket:

[0064] In this embodiment, the object distance d1 of the high-magnification objective lens 28 is 7mm, the thickness d2 of the upper optical glass window 5 is 3mm, and the required micro-fuel combustion height (the maximum distance from the bottom of the upper optical glass window 5 to the upper surface of the glass pad 14) d3 is 2mm. Therefore, in order to achieve clear imaging, the thickness d4 of the glass pad 14 should satisfy the following equation: d4 + d3 + d2 = d1; it can be calculated that d4 = 2mm. Therefore, in this embodiment, the thickness of the glass pad 14 is selected as 2mm.

[0065] Step 3, sample injection:

[0066] A vacuum pump 30 is installed at the gas outlet 18 of the combustion chamber to evacuate the gas in the combustion chamber and maintain a vacuum environment.

[0067] Place the single microparticle fuel 16 on the micro-combustion chip 15, and then tighten the upper cover 3 and the heat insulation top plate 12 in sequence. During the assembly process, the bolts of the upper cover 3 should be tightened diagonally to avoid loose connection caused by tilting, and the optical lens should be embedded in the lens groove of the upper cover 3 to avoid damage to the upper optical window 5 caused by impact.

[0068] Step 4: High temperature and high pressure environment generation:

[0069] The annular cast copper heating plate 10 is energized to heat the environment inside the combustion chamber 9. At the same time, the temperature control box 35 detects and controls the heating temperature of the annular cast copper heating plate 10 to maintain a stable temperature. After a high-temperature environment is formed and stabilized for a period of time, the gas cylinder 34 is connected to the combustion chamber inlet 17 through the gas supply pipeline and injects gas into the combustion chamber 9.

[0070] A mass flow controller 31 is installed between the gas cylinder 34 and the combustion chamber inlet 17 to control the flow and mass of the gas, and the pressure change in the combustion chamber 9 is monitored by the pressure gauge 29.

[0071] Once the pressure inside the combustion chamber 9 reaches the set value, the gas cylinder 34 stops supplying gas through the solenoid valve on the gas supply pipeline at the inlet of the mass flow controller 31, thereby stopping the pressurization and observing the pressure holding situation.

[0072] Step 5: Ignite and burn:

[0073] This embodiment employs laser ignition. First, the laser 27 is activated, and the laser power is adjusted. The laser beam is reflected vertically through a first-stage total reflection mirror 25, a second-stage total reflection mirror 26, and a dichroic mirror 24, entering the high-temperature, high-pressure combustion chamber 1 to ignite and burn individual particulate fuel particles 6. To eliminate interference from the laser on the ignition and combustion phenomenon, a filter 23 is placed under the high-speed camera 22. Simultaneously with the laser ignition operation, the high-speed camera 22 begins to... Figure 5 The experimental process shown was filmed and recorded.

[0074] Step 6: After the test is completed, open the solenoid valve and pressure reducing valve on the combustion chamber outlet 18 pipeline to depressurize; then inject refrigerant gas into the heat insulation layer 13 through the gas cylinder 34 to cool down the high-temperature and high-pressure combustion chamber 1.

[0075] A safety valve 32 is installed in the air supply line connected to the air inlet 17 of the combustion chamber. During combustion, when the air pressure in the combustion chamber 9 is higher than the preset pressure, the safety valve 32 can automatically open to relieve the pressure.

[0076] A buffer tank 33 is provided at the outlet of the gas cylinder 34, which can premix the working gas, such as nitrogen and oxygen.

[0077] It should be noted that the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

Claims

1. A high-temperature, high-pressure single-particle fuel micro-combustion device, characterized in that: It includes a high-temperature and high-pressure combustion chamber, a high-speed camera, a laser, a high-magnification objective lens, and a background light source; The high-temperature and high-pressure combustion chamber includes a heat-insulating shell, a heat-insulating top plate, a combustion chamber body, and a cover, with the cover fixed to the side wall of the combustion chamber body; The heat insulation shell is a barrel-shaped structure with an opening on one side. The combustion chamber body and the cover are placed inside the heat insulation shell. The bottom of the heat insulation shell is equipped with a column to support the combustion chamber body. A heat-insulating top plate is installed on the opening side of the heat-insulating outer shell; a heat-insulating cavity is provided between the combustion chamber body and the heat-insulating outer shell and heat-insulating top plate, which is insulated by air. A combustion chamber is provided in the middle of the combustion chamber body; a mirror groove with the same shape as the optical lens is milled on the cover, which is used to install the optical lens and restrict its movement to form an optical glass window; openings are provided on opposite sides of the combustion chamber, which are respectively opposite to the first optical glass window and the second optical glass window; a sealing gasket is provided between the first optical glass window, the second optical glass window and the combustion chamber. The heat-insulating outer shell and heat-insulating top plate have holes at positions relative to the first and second optical glass windows to facilitate light transmission, observation, and photography. The combustion chamber body has a combustion chamber air inlet and a combustion chamber air outlet leading to the combustion chamber. The combustion chamber air inlet and the combustion chamber air outlet are connected by a slot in the combustion chamber body. The combustion chamber air inlet fills and pressurizes the sealed space formed by the combustion chamber and the optical glass window; the combustion chamber air outlet exhausts and releases pressure. A groove is provided in the middle of the combustion chamber body to nest a glass gasket and restrict its movement. A micro-combustion plate is placed on the glass gasket, and during combustion, a single microparticle fuel is placed on the micro-combustion plate. An annular cast copper heating plate surrounds the combustion chamber relative to the outside of the glass gasket. The heating temperature of the annular cast copper heating plate is controlled and monitored by an external temperature control box. A high-speed camera and a high-magnification objective lens are installed outside the first optical glass window for photography and imaging; a background light source is installed outside the second optical glass window. The axes of the high-speed camera and the high-magnification objective lens are on the same axis as the geometric centers of the first and second optical glass windows, as well as the single particulate fuel and the background light source; the laser emitted by the laser enters the high-temperature and high-pressure combustion chamber vertically through the total reflection mirror, the color mirror, the high-magnification objective lens and the first optical glass window.

2. The high-temperature, high-pressure single-particle fuel micro-combustion device as described in claim 1, characterized in that: The combustion chamber body and cover are made of aluminum alloy.

3. The high-temperature, high-pressure single-particle fuel micro-combustion device as described in claim 1, characterized in that: A mass flow controller is connected to the air inlet of the combustion chamber via a pipeline; a safety valve is also installed on the air inlet pipeline of the mass flow controller.

4. The high-temperature and high-pressure single-particle fuel micro-combustion device as described in claim 3, characterized in that: The outlet of the mass flow controller is connected to the inlet of the combustion chamber via a pipeline, and the inlet of the mass flow controller is connected to the outlet of the buffer tank via a pipeline. A solenoid valve is installed on the inlet pipeline of the mass flow controller. The inlet of the buffer tank is connected to the outlet of the gas cylinder via a pipeline, and a pressure reducing valve is installed on the inlet pipeline of the buffer tank.

5. The high-temperature, high-pressure single-particle fuel micro-combustion device as described in claim 1, characterized in that: One branch of the combustion chamber outlet is connected in series with a solenoid valve and a pressure reducing valve via a pipeline; the other branch of the combustion chamber outlet is connected to a pressure gauge via a pipeline, and the outlet of the pressure gauge is connected to a vacuum pump via a pipeline. A solenoid valve is installed on the pipeline of the pressure gauge outlet.

6. The high-temperature and high-pressure single-particle fuel micro-combustion device as described in claim 1, characterized in that: The optical glass window is made of quartz glass.

7. The high-temperature, high-pressure single-particle fuel micro-combustion device as described in claim 1, characterized in that: The high-speed camera is equipped with a filter.

8. A method for micro-combustion of high-temperature and high-pressure single-particle fuel based on the device of claim 1, characterized in that: Specifically, the steps include the following: The first step is selecting the optical observation window: Based on the selected window shape and the set maximum pressure, the required standard thickness of the window glass is calculated according to the pressure and the standard thickness formula of the optical glass window. The standard thickness t of an optical glass window is calculated as follows: Where F is the pressure exerted by the gas in the combustion chamber on the optical glass window, [τ] is the tensile strength limit, m = 1 / μ, Poisson's ratio μ = 0.17; the second step is the selection of the glass gasket: Based on the imaging conditions in the experiment, the required thickness of the glass gasket is calculated; Step 3, sample injection: Place the micro fuel on the micro-combustion plate, and then tighten the cap and the heat insulation plate in sequence; Step 4: Generation of a high-temperature, high-pressure combustion environment: The annular cast copper heating plate is powered on, which heats the annular cast copper heating plate to create a high temperature in the combustion chamber. The heating temperature of the annular cast copper heating plate is controlled by a temperature control box. Gas is then injected into the combustion chamber through the combustion chamber air inlet to create a high pressure in the combustion chamber. The pressure holding status is monitored by a pressure gauge. Step 5, ignition and combustion: igniting and burning individual microparticle fuels using laser ignition; The sixth step is to depressurize the combustion chamber through the exhaust port and cool the combustion chamber cavity.

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