Method, system, apparatus and device for determining aluminum particle combustion two-phase flow

Abstract

This application provides a method, system, apparatus, and device for determining the two-phase flow of aluminum particle combustion, relating to aerospace propulsion technology and multiphase flow combustion diagnostics. The method includes: under stable combustion conditions of aluminum powder flames, alternately acquiring at least three types of images according to a preset time-series control parameter set; the images include a flame self-illumination image without active illumination, a multispectral extinction image under broadband active illumination, and a particle scattering image under laser sheet illumination. Using the flame self-illumination image, pixel-level background subtraction is performed on the multispectral extinction image and the particle scattering image respectively. Cross-correlation calculation is performed on the background-subtracted particle scattering image to obtain the velocity vector field and the spatial distribution information of aluminum powder particles; based on the background-subtracted multispectral extinction image, the local extinction coefficient distribution of the flame radial cross-section is obtained. This achieves the reconstruction of the flow field dynamics characteristics, spatial distribution of unburned aluminum particles and alumina smoke, and particle size evolution characteristics during aluminum powder combustion.

Description

Technical Field

[0001] This application relates to the fields of aerospace propulsion technology and multiphase flow combustion diagnostics, and more specifically, to a method, system, apparatus and equipment for determining two-phase flow in aluminum particle combustion. Background Technology

[0002] Currently, aluminum powder, as a metallic fuel with high calorific value and high safety, is widely used in solid rocket engines, hybrid-electric rockets, and novel metallic fuel propellants. The combustion process of aluminum powder involves multi-physics coupling, including gas-solid two-phase flow, high-temperature reaction kinetics, and the formation of condensed products. Its combustion characteristics directly affect the combustion efficiency, stability, and thermal protection design of the propulsion system. Therefore, conducting diagnostic research on the aluminum powder combustion process has significant theoretical and engineering value for revealing the combustion mechanism of metallic fuels and optimizing engine performance.

[0003] In existing technologies, diagnostic techniques for aluminum powder combustion mainly focus on the measurement of thermodynamic parameters. For example, existing technology discloses an experimental system for analyzing the combustion of aluminum powder at different concentrations. This system consists of a high-voltage power supply, an aerosol feeder, a high-pressure chamber, a multi-element flat-flame burner, a spectrometer, a high-speed camera, a digital camera, and a laser igniter. Its working principle is as follows: the multi-element flat-flame burner and the aluminum particle aerosol generator are placed in the high-pressure chamber. Combustion gas is introduced from the bottom of the burner, and oxidizing gas is introduced from the top, mixing in a capillary tube. The laser igniter is then activated to ignite the aluminum powder at the capillary tube opening. Through a quartz observation window, a high-speed camera records the real-time flame state, a spectrometer records spectral data, and a digital camera captures real-time images, thereby obtaining information related to the flame structure and temperature. This scheme can achieve static parameter measurement of aluminum powder flames, providing some guidance for the design of aluminum-containing power devices.

[0004] However, the aforementioned existing technologies still have the following shortcomings in practical applications: First, there is a complex coupling relationship between the aluminum powder combustion process and the flow field structure. The distribution of the combustion reaction zone is closely related to particle motion and turbulent mixing, and obtaining only temperature information is insufficient to fully reveal the combustion mechanism. Due to the extremely high brightness of the aluminum powder flame and the extremely fast particle motion, existing technologies struggle to extract the particle displacement vector under strong radiation backgrounds, resulting in a lack of spatial correlation between the velocity field and the combustion reaction zone, making it impossible to obtain the dynamic characteristics of the flow field. Second, aluminum powder combustion generates condensed alumina particles (nanometer to submicron scale) with high number density and high temperature. These particle groups significantly impact the radiation transmission environment inside the engine and also cause severe two-phase flow erosion of the power system nozzle. However, the unburned aluminum particles and the generated alumina smoke in the aluminum powder flame are optically intertwined, and existing technologies cannot distinguish their optical contributions at a single wavelength. Therefore, they lack the ability to independently obtain the particle size and number density characteristics of alumina particles, making it difficult to assess their erosion effect on the nozzle and providing accurate experimental data for engine radiation transmission modeling. Summary of the Invention

[0005] The purpose of this application is to provide a method, system, device, and equipment for determining the two-phase flow of aluminum particle combustion, aiming to physically eliminate the strong background interference of high-temperature flame self-luminescence, and to reconstruct the flow field dynamics characteristics, spatial distribution of unburned aluminum particles and alumina smoke, and particle size evolution characteristics during aluminum powder combustion.

[0006] Firstly, a method for determining the two-phase flow of aluminum particle combustion is provided, the method including: Under the stable combustion state of aluminum powder flame, at least three types of images are alternately acquired according to a preset time sequence control parameter set; the images include flame self-luminous images without active illumination, multispectral extinction images under broadband active illumination, and particle scattering images under laser sheet illumination. Using the flame self-luminous image, pixel-level background subtraction is performed on the multispectral extinction image and the particle scattering image, respectively. Cross-correlation calculations were performed on the particle scattering image after background subtraction to obtain the velocity vector field characterizing the dynamic properties of the gas phase and the particle phase, as well as the spatial distribution information of aluminum powder particles; based on the multispectral extinction image after background subtraction, the local extinction coefficient distribution of the flame radial section was obtained. Based on the preset initial particle size distribution of aluminum powder, the spatial distribution information, and the local extinction coefficient distribution, the two-phase flow parameters of the condensed product alumina are obtained; these two-phase flow parameters include volume fraction and particle size distribution.

[0007] Secondly, a system for determining the two-phase flow of aluminum particle combustion is provided, the system comprising: An aluminum powder supply system includes aluminum powder, a stepper motor-driven piston, a vibration device, and an aluminum powder supply device housing; the aluminum powder supply system is used to provide stable and controllable aluminum powder fuel. A laser ignition system includes a carbon dioxide laser power supply, a carbon dioxide laser tube, a corner mirror, and a cooling water tank; the laser ignition system is used for non-contact ignition of aluminum powder. A burner used to generate an aluminum powder premixed flame based on the ignited aluminum powder; A multispectral extinction and PIV diagnostic system includes a quasi-continuous laser, a laser shaping lens system, a broadband stroboscopic LED light source, a three-way filter, a color high-speed camera, and an imaging computer; the imaging computer is configured to perform the steps of the first aspect.

[0008] Thirdly, an apparatus for determining the two-phase flow of aluminum particle combustion is provided, the apparatus comprising: The acquisition module is used to alternately acquire at least three types of images under the stable combustion state of aluminum powder flame according to a preset time sequence control parameter set; the images include flame self-luminous images without active illumination, multispectral extinction images under broadband active illumination, and particle scattering images under laser sheet illumination. The background subtraction module is used to perform pixel-level background subtraction on the multispectral extinction image and the particle scattering image respectively using the flame self-luminous image; The calculation module is used to perform cross-correlation calculations on the particle scattering image after background subtraction to obtain the velocity vector field characterizing the dynamic properties of the gas phase and the particle phase, as well as the spatial distribution information of aluminum powder particles; based on the multispectral extinction image after background subtraction, the local extinction coefficient distribution of the flame radial section is obtained. The generation module is used to obtain the two-phase flow parameters of the condensed product alumina based on the preset initial particle size distribution of aluminum powder, the spatial distribution information, and the local extinction coefficient distribution; the two-phase flow parameters include volume fraction and particle size distribution.

[0009] Fourthly, an electronic device is provided, which includes a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus. Memory, used to store computer programs; When a processor executes a program stored in memory, it implements any of the steps described in the first aspect above.

[0010] Fifthly, a computer-readable storage medium is provided, wherein a computer program is stored therein, and when executed by a processor, the computer program implements the steps of any of the methods described in the first aspect above.

[0011] This application provides a method, system, apparatus, and device for determining the two-phase flow of aluminum particle combustion. Under stable combustion conditions of an aluminum powder flame, at least three types of images are alternately acquired according to a preset time-series control parameter set. These images include a flame self-luminous image without active illumination, a multispectral extinction image under broadband active illumination, and a particle scattering image under laser sheet illumination. Using the flame self-luminous image, pixel-level background subtraction is performed on the multispectral extinction image and the particle scattering image. Cross-correlation calculations are performed on the background-subtracted particle scattering image to obtain the velocity vector field characterizing the dynamics of the gas and particle phases and the spatial distribution information of the aluminum powder particles. Based on the background-subtracted multispectral extinction image, the local extinction coefficient distribution of the flame radial cross-section is obtained. According to the preset initial particle size distribution, spatial distribution information, and local extinction coefficient distribution of the aluminum powder, the two-phase flow parameters of the condensed product alumina are obtained; these two-phase flow parameters include volume fraction and particle size distribution. This scheme precisely controls the steady-state supply of aluminum powder and carbon dioxide laser ignition, and uses alternating triggering on a time scale to sequentially capture images of flame self-luminescence without active illumination, multispectral extinction images under broadband active illumination, and particle scattering images under laser sheet illumination. Through pixel-level background subtraction and cross-correlation calculations, the two-phase flow parameters of the condensed alumina product are obtained. This aims to physically eliminate the strong background interference from the high-temperature flame self-luminescence, reconstructing the flow field dynamics, spatial distribution of unburned aluminum particles and alumina smoke, and particle size evolution characteristics during aluminum powder combustion. It solves the technical problem of existing technologies being unable to simultaneously acquire the flow field dynamics information of aluminum powder flames and the particle size distribution characteristics of condensed alumina products. This achieves the synchronous reconstruction of the combustion dynamics flow field and combustion structure, establishing a spatial correlation between two-phase flow and chemical reaction at the experimental level. It provides an experimental benchmark for the verification and correction of aluminum powder combustion models, and provides experimental basis for the refined design of high-energy-density power systems, facilitating the optimization of engine combustion efficiency and the suppression of unstable combustion. Attached Figure Description

[0012] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0013] Figure 1 A flowchart illustrating a method for determining two-phase flow during aluminum particle combustion, provided in an embodiment of this application; Figure 2 This is a schematic diagram of a device for determining the two-phase flow of aluminum particle combustion, provided in an embodiment of this application. Figure 3A flowchart illustrating a method for determining two-phase flow during aluminum particle combustion, provided in an embodiment of this application; Figure 4 A schematic diagram of multispectral extinction and PIV diagnostic timing provided in this application embodiment; Figure 5 This is a schematic diagram of a device for determining the two-phase flow of aluminum particle combustion, provided in an embodiment of this application. Figure 6 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Detailed Implementation

[0014] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application. Unless otherwise defined, the technical or scientific terms used in this application should have the ordinary meaning understood by those skilled in the art. The words "first," "second," and similar terms used in this application do not indicate any order, quantity, or importance, but are only used to distinguish different components. The words "comprising" or "including," etc., mean that the element or object preceding the word covers the element or object listed after the word and its equivalents, but do not exclude other elements or objects. The words "connected," "coupled," or "connected," etc., are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. "Up," "down," "left," "right," etc., are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0015] For ease of understanding, the terms used in the embodiments of this application are explained below: PIV: Particle Image Velocimetry.

[0016] Abel inversion: also known as Abel inverse transformation, is a mathematical process used to describe the reconstruction of axisymmetric field distributions (three-dimensional / radial distributions) from projected data (two-dimensional).

[0017] Projected optical thickness: specifically refers to the total optical thickness measured directly along a specific optical path; Optical thickness: a general term.

[0018] The method for determining the two-phase flow of aluminum particle combustion provided in this application embodiment can be applied to electronic devices, terminal devices, devices or apparatuses for determining the two-phase flow of aluminum particle combustion, or other devices or apparatuses capable of executing this embodiment, and there are no limitations on this application. Electronic devices include imaging computers, etc.; in this embodiment, the imaging computer is used as the executing entity for description.

[0019] The terminal can be a user equipment (UE) such as a mobile phone, smartphone, laptop computer, digital broadcast receiver, personal digital assistant (PDA), or tablet computer (PAD), handheld device, in-vehicle device, wearable device, computing device, or other processing device connected to a wireless modem, mobile station (MS), or mobile terminal. This terminal has the ability to communicate with one or more core networks via a radio access network (RAN).

[0020] The preferred embodiments of this application are described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit this application. Furthermore, the embodiments and features in the embodiments of this application can be combined with each other without conflict.

[0021] Figure 1 This is a schematic flowchart illustrating a method for determining the two-phase flow of aluminum particle combustion, provided in an embodiment of this application. Figure 1 As shown, the method may include: Step S101: Under the stable combustion state of aluminum powder flame, at least three types of images are alternately acquired according to the preset time sequence control parameter set; the images include flame self-luminous images without active illumination, multispectral extinction images under broadband active illumination, and particle scattering images under laser sheet illumination.

[0022] For example, Figure 2 This is a schematic diagram of a device for determining the two-phase flow of aluminum particle combustion, provided in an embodiment of this application. Figure 2 As shown, it includes: 1. Burner, 2. 30W quasi-continuous laser (455nm), 3. Laser shaping lens system, 4. Aluminum powder, 5. Stepper motor driven piston, 6. Vibration device, 7. Aluminum powder supply device housing, 8. Carbon dioxide laser power supply, 9. Carbon dioxide laser tube, 10. Corner mirror, 11. Cooling water tank, 12. High-power broadband strobe LED light source, 13. Quartz protective screen, 14. Three-way filter, 15. Microscope lens, 16. Color high-speed camera, 17. Imaging computer.

[0023] In this step, the first step is to perform test preparation and environmental calibration. Specifically, according to... Figure 2The structural diagram shows the installation of each component, ensuring optical axis alignment. The stability of the aluminum powder supply 4 is checked using the vibration device 6 and the stepper motor-driven piston 5. After confirming stability, in the un-ignited state, the quasi-continuous laser and high-power broadband stroboscopic LED light source are turned on. Background images at different power levels are acquired using the quasi-continuous laser and a color high-speed camera to determine the initial transmittance benchmark of the system. Simultaneously, the preset timing control parameter set is adjusted. This preset timing control parameter set refers to the exposure time sequence of the color high-speed camera, the pulse time sequence of the quasi-continuous laser, and the time sequence of the broadband stroboscopic LED light source, ensuring the cyclic pulse width and interval of each state to prevent interference between states.

[0024] The exposure time series of the color high-speed camera includes the exposure start time and exposure duration; the pulse time series of the quasi-continuous laser includes the pulse on-time, pulse width, and off-time; and the time series of the broadband stroboscopic LED light source includes the pulse on-time, pulse width, and off-time. The states include broadband stroboscopic LED light source off + quasi-continuous laser off, broadband stroboscopic LED light source on + quasi-continuous laser off, and broadband stroboscopic LED light source off + quasi-continuous laser on. Multispectral extinction images are acquired using a color high-speed camera 16 with R / G / B three channels, and a three-pass filter 14. The three-pass filter 14 has three narrow bandpass windows corresponding to the R, G, and B channels of the color high-speed camera, respectively. Laser sheet light is generated by a 455nm wavelength quasi-continuous laser in conjunction with a laser shaping lens system 3; broadband active illumination is provided by a broadband stroboscopic LED light source 12.

[0025] Then, ignition and steady-state combustion control are executed. Specifically, the stepper motor is started to allow aluminum powder to enter the burner at a preset rate, and the carrier gas is turned on to form a stable premixed jet. The carbon dioxide laser power supply 8 is briefly turned on, and the laser is focused above the nozzle through the corner mirror 10 to induce the aluminum powder to heat up and ignite until a stable Bunsen burner flame is formed.

[0026] Under stable combustion conditions of the aluminum powder flame, the imaging computer 17 triggers the color high-speed camera 16 to enter recording mode. Within a very short time window, according to a preset set of timing control parameters, a set of three types of images is acquired. This set is then repeated, with the camera continuously recording images within each time window, forming a continuous data stream. The data is then classified and stored according to signal type, resulting in a sequence of three types of images. The images include: the first type, self-luminous flame images without active illumination, where the self-luminous flame image represents the self-luminous signal of the aluminum powder flame to be removed. The first type is the background image, where the flame's self-illumination image records the blackbody radiation background of the flame itself for physical-level noise subtraction; the second type is the multispectral extinction image under broadband active illumination, where the multispectral extinction image represents the extinction signal. Multispectral extinction images are used to record the intensity of the three-wavelength LED after passing through the flame, and are used to calculate the optical thickness; the third type is particle scattering images under laser sheet illumination, where the particle scattering images are PIV scattering signals. It is used to record the scattering signals of aluminum particles and aluminum oxide under 455 nm laser light, and is used for subsequent PIV flow field calculations and Abel inversion calculations. For example, the preset timing control parameter set can be microsecond-level timing.

[0027] Step S102: Using the flame self-luminous image, perform pixel-level background subtraction on the multispectral extinction image and the particle scattering image respectively.

[0028] For example, the self-luminous signal of aluminum powder flame is utilized. Extinction signals respectively and PIV scattering signal Pixel-level subtraction is performed to remove strong flame radiation interference, generating a particle scattering image after background subtraction and a multispectral extinction image after background subtraction.

[0029] Step S103: Perform cross-correlation calculation on the particle scattering image after background subtraction to obtain the velocity vector field characterizing the dynamic characteristics of the gas phase and particle phase and the spatial distribution information of aluminum powder particles; based on the multispectral extinction image after background subtraction, obtain the local extinction coefficient distribution of the radial section of the flame.

[0030] For example, the PIV cross-correlation algorithm is performed on the particle scattering image sequence after background subtraction to extract the velocity vector field of particle motion. The velocity vector field represents the velocity vector field of gas phase and particle phase dynamics. Based on the multispectral extinction image after background subtraction, the transmittance (i.e., projected optical thickness) of condensed particles to radiation of different wavelengths is calculated, and an inverse Abel transform is performed to obtain the local extinction coefficient distribution of the radial cross section of the flame.

[0031] Step S104: Based on the preset initial particle size distribution, spatial distribution information and local extinction coefficient distribution of aluminum powder, the two-phase flow parameters of the condensed product alumina are obtained; the two-phase flow parameters include volume fraction and particle size distribution.

[0032] For example, the preset initial particle size distribution of aluminum powder and the spatial distribution information of aluminum powder particles obtained based on PIV are used as constraints. The two-phase flow parameters of the condensed product alumina are calculated and separated using the extinction gradient at different wavelengths. The two-phase flow parameters include volume fraction and equivalent particle size distribution.

[0033] The method provided in this application, under stable combustion conditions of aluminum powder flame, alternately acquires at least three types of images according to a preset time-series control parameter set; the images include flame self-luminescence images without active illumination, multispectral extinction images under broadband active illumination, and particle scattering images under laser sheet illumination. Using the flame self-luminescence images, pixel-level background subtraction is performed on the multispectral extinction images and particle scattering images respectively. Cross-correlation calculations are performed on the background-subtracted particle scattering images to obtain the velocity vector field characterizing the dynamic properties of the gas phase and particle phase, and the spatial distribution information of aluminum powder particles; based on the background-subtracted multispectral extinction images, the local extinction coefficient distribution of the flame radial cross section is obtained. According to the preset initial particle size distribution, spatial distribution information, and local extinction coefficient distribution of aluminum powder, the two-phase flow parameters of the condensed product alumina are obtained; these two-phase flow parameters include volume fraction and particle size distribution. This scheme precisely controls the steady-state supply of aluminum powder and carbon dioxide laser ignition, and uses alternating triggering on a time scale to sequentially capture images of flame self-luminescence without active illumination, multispectral extinction images under broadband active illumination, and particle scattering images under laser sheet illumination. Through pixel-level background subtraction and cross-correlation calculations, the two-phase flow parameters of the condensed alumina product are obtained. This aims to physically eliminate the strong background interference from the high-temperature flame self-luminescence, reconstructing the flow field dynamics, spatial distribution of unburned aluminum particles and alumina smoke, and particle size evolution characteristics during aluminum powder combustion. It solves the technical problem of existing technologies being unable to simultaneously acquire the flow field dynamics information of aluminum powder flames and the particle size distribution characteristics of condensed alumina products. This achieves the synchronous reconstruction of the combustion dynamics flow field and combustion structure, establishing a spatial correlation between two-phase flow and chemical reaction at the experimental level. It provides an experimental benchmark for the verification and correction of aluminum powder combustion models, and provides experimental basis for the refined design of high-energy-density power systems, facilitating the optimization of engine combustion efficiency and the suppression of unstable combustion.

[0034] Figure 3 This application provides a flowchart illustrating a method for determining the two-phase flow of aluminum particle combustion. Figure 3 As shown, in this embodiment... Figure 1 Based on the embodiments, the method is described in detail below, and the method includes: Step S201: Under the stable combustion state of aluminum powder flame, at least three types of images are alternately acquired according to the preset time sequence control parameter set; the images include flame self-luminous images without active illumination, multispectral extinction images under broadband active illumination, and particle scattering images under laser sheet illumination.

[0035] In one example, S201 includes: a timing control parameter set including: the pulse on-time, pulse width, and off-time of the quasi-continuous laser; the pulse on-time, pulse width, and off-time of the broadband stroboscopic LED light source; the exposure start time and exposure duration of the color high-speed camera; the timing control parameter set is configured to control the color high-speed camera to sequentially acquire images in the following three states within a continuous time window: first state: quasi-continuous laser off, broadband stroboscopic LED light source off; second state: quasi-continuous laser off, broadband stroboscopic LED light source on; third state: quasi-continuous laser on, broadband stroboscopic LED light source off.

[0036] In one example, the multispectral extinction image is obtained by using a color high-speed camera with three channels (R / G / B) and a three-pass filter, which has three narrow bandpass windows corresponding to the R, G, and B channels of the color high-speed camera, respectively.

[0037] In one example, the laser sheet light is generated by a quasi-continuous laser with a wavelength of 455 nm in conjunction with a laser shaping lens system; broadband active illumination is provided by a broadband strobe LED light source.

[0038] For example, this step is the same as step S101, and will not be described in detail here.

[0039] Step S202: Using the flame self-luminous image, perform pixel-level background subtraction on the multispectral extinction image and the particle scattering image respectively.

[0040] For example, this step is the same as step S102, and will not be described in detail here.

[0041] Step S203: Perform cross-correlation calculation on the particle scattering image after background subtraction to obtain the velocity vector field characterizing the dynamic characteristics of the gas phase and particle phase and the spatial distribution information of aluminum powder particles.

[0042] In one example, the velocity vector field of particle motion is used to characterize the transient flow field dynamics during the combustion of aluminum particles and is synchronously associated with the flame front space.

[0043] For example, cross-correlation calculations are performed on the particle scattering image after background subtraction to obtain the velocity vector field characterizing the dynamic characteristics of the gas phase and particle phase and the spatial distribution information of aluminum powder particles; the velocity vector field of particle motion is used to represent the transient flow field dynamic characteristics during the combustion process of aluminum particles and is synchronously correlated with the flame front space.

[0044] Step S204: Based on the multispectral extinction image after background subtraction, obtain the local extinction coefficient distribution of the radial cross section of the flame.

[0045] In one example, S204 includes: calculating the optical thickness at at least two different wavelengths based on the multispectral extinction image after background subtraction; and inverting the optical thickness at each wavelength into the local extinction coefficient distribution of the radial cross section of the flame by means of inverse Abel transformation.

[0046] For example, based on the multispectral extinction image after background subtraction, the optical thickness at at least two different wavelengths is calculated; and the optical thickness at each wavelength is inverted into the local extinction coefficient distribution of the radial cross section of the flame by inverse Abel transformation.

[0047] Step S205: Based on the preset initial particle size distribution, spatial distribution information and local extinction coefficient distribution of aluminum powder, the two-phase flow parameters of the condensed product alumina are obtained; the two-phase flow parameters include volume fraction and particle size distribution.

[0048] In one example, S205 includes: obtaining the projected optical thickness at least two different wavelengths corresponding to each pixel point based on the multispectral extinction image after background subtraction; discretizing the flame cross section based on the projected optical thickness of each pixel point based on the axisymmetric structure of the flame, and inverting the projected optical thickness at each wavelength into the local extinction coefficient distribution of the flame radial cross section through inverse Abel transformation; using the preset initial particle size distribution of aluminum powder and the spatial distribution information of aluminum powder particles as constraints, and using the local extinction coefficient distribution at least two different wavelengths, obtaining the number density distribution and equivalent particle size distribution of alumina particles on the flame radial cross section through fitting multispectral extinction data.

[0049] For example, the implementation principle of the multispectral extinction method is as follows: using a color high-speed camera with a three-pass filter 14, images are captured of radiation in different spectral bands and radiation generated by the condensed particles in the flame themselves, which pass through the condensed particles and undergo scattering, absorption and other processes. The projected optical thickness of the particle group in different bands is calculated, and the number density of the condensed particles and the spatial distribution characteristics of the particle size are reconstructed.

[0050] Among them, the spontaneously generated radiation energy of particles captured by a single pixel of a color high-speed camera. It can be represented as: (1) in, To capture the band, For the exposure time, and For pixel size, For the capture efficiency of the optical system, To capture the angle constant, It is the optical absorption coefficient of a particle at a specific location. This refers to the optical blackbody radiation intensity of a particle at a specific location, where "specific location" refers to a spatial micro-element (i.e., the location of the radiation source) within the flame along the optical path. Simultaneously, in the third state—with the broadband stroboscopic LED light source off and the quasi-continuous laser on—the radiation energy of the laser source captured by a single pixel of the high-speed camera after passing through the particle group is... (i.e., flame self-luminescence + laser scattering) can be represented as:

[0051] in, This represents the radiant flux density of the laser source. This represents the attenuation factor of the Beer-Lambert law.

[0052] In the second state, where the broadband stroboscopic LED light source is on and the quasi-continuous laser is off, the energy captured by a single pixel (i.e., flame self-emission + LED transmission) can be expressed as:

[0053] Similarly, in the first state where the broadband strobe LED light source is off and the quasi-continuous laser is off, the energy captured by a single pixel (i.e., only the flame emits its own light) can be expressed as:

[0054] At a specific wavelength, the energy difference captured by a single pixel can be expressed as:

[0055] A specific optical path refers to the straight-line propagation path from the light source to a single pixel of the camera. The projected optical thickness along a specific optical path can be expressed as:

[0056] in, This indicates the background signal (dark background) when there is no ignition and no active lighting. This represents the background signal (LED transmission intensity without flame) when the LED light source is not ignited and only provides broadband strobe illumination. This means that when the flame is not ignited, the dark background is subtracted to obtain the LED transmission signal without flame (i.e., the initial transmittance reference of the system). This indicates that after ignition, the signal when the broadband strobe LED light source is turned on is subtracted from the flame's self-luminescence to obtain the actual LED transmission signal passing through the flame. Then, the projected optical thickness at least two different wavelengths corresponding to each pixel can be obtained according to formula (6). The projected optical thickness is the transmittance of condensed particles to radiation in different wavelength bands. At this time, the optical thickness caused by the presence of the flame is obtained, eliminating systematic errors such as LED light source intensity fluctuations and optical system transmittance, and improving accuracy.

[0057] Assuming the flame is axisymmetric, the measurement results of each pixel can be used as a basis. The flame structure is discretized, and the projected optical thickness at different locations within the flame is derived. The projected optical thickness at a specific location can be expressed as:

[0058] in, For having a radius Alumina particles at a wavelength of The attenuation cross section formed during time, This represents the volume fraction of alumina at that location. A specific location refers to a specific discrete position on the radial cross-section of the flame after the inverse Abel transformation (identified by radial coordinates r or y, i.e., a spatial point inside the flame; the "specific optical path" and the specific location form a "projection → spatial distribution" correspondence). The local extinction coefficient distribution at each radial location can be expressed as the integral relationship between the attenuation cross-section and volume fraction of alumina particles according to formula (7). Based on the projected optical thickness formed by alumina at different wavelengths, the volume fraction and average particle size of alumina at that location can be calculated. Then, through Abel inversion, the distribution characteristics of alumina in the flame can be obtained. It should be noted that since aluminum particles themselves also form optical thickness, it is necessary to measure the particle size distribution of aluminum particles in advance and use PIV technology to accurately capture the aluminum powder flame front, thereby obtaining the spatial distribution characteristics of aluminum particles. When performing Abel inversion calculation, the optical thickness of aluminum particles is given as a known quantity.

[0059] The method provided in this application, under stable combustion conditions of aluminum powder flame, alternately acquires at least three types of images according to a preset time-series control parameter set; the images include a flame self-luminous image without active illumination, a multispectral extinction image under broadband active illumination, and a particle scattering image under laser sheet illumination. Using the flame self-luminous image, pixel-level background subtraction is performed on the multispectral extinction image and the particle scattering image respectively. Cross-correlation calculation is performed on the background-subtracted particle scattering image to obtain the velocity vector field characterizing the dynamic properties of the gas phase and the particle phase, and the spatial distribution information of the aluminum powder particles. Based on the background-subtracted multispectral extinction image, the local extinction coefficient distribution of the flame radial cross section is obtained. According to the preset initial particle size distribution, spatial distribution information, and local extinction coefficient distribution of the aluminum powder, the two-phase flow parameters of the condensed product alumina are obtained; these two-phase flow parameters include volume fraction and particle size distribution. By precisely controlling the steady-state supply of aluminum powder and carbon dioxide laser ignition, and utilizing alternating triggering on a time scale, the system sequentially captures images of flame self-luminescence without active illumination, multispectral extinction images under broadband active illumination, and particle scattering images under laser sheet illumination. Through pixel-level background subtraction and cross-correlation calculations, the two-phase flow parameters of the condensed alumina product are obtained. This aims to physically eliminate the strong background interference of high-temperature flame self-luminescence, and reconstruct the flow field dynamics, spatial distribution of unburned aluminum particles and alumina smoke, and particle size evolution characteristics during aluminum powder combustion. This solves the technical problem that existing technologies cannot simultaneously acquire the flow field dynamics information of aluminum powder flame and the particle size distribution characteristics of condensed alumina products. It achieves the synchronous reconstruction of combustion dynamics flow field and combustion structure, establishes the spatial correlation between two-phase flow and chemical reaction at the experimental level, provides experimental benchmarks for the verification and correction of aluminum powder combustion models, and provides experimental basis for the refined design of high-energy-density power systems, facilitating the optimization of engine combustion efficiency and the suppression of unstable combustion.

[0060] In one embodiment, Figure 4 A schematic diagram of multispectral extinction and PIV diagnostic timing provided for embodiments of this application, as shown below. Figure 4 As shown, in time series 1, 2, and 3, from left to right, the components include: a high-power broadband strobe LED light source; a burner; and a color high-speed camera. , , .

[0061] In one embodiment, this application also provides a system for determining the two-phase flow of aluminum particle combustion, the system comprising: An aluminum powder supply system includes aluminum powder, a stepper motor-driven piston, a vibration device, and an aluminum powder supply device housing; the aluminum powder supply system is used to provide stable and controllable aluminum powder fuel. The laser ignition system includes a carbon dioxide laser power supply, a carbon dioxide laser tube, a corner mirror, and a cooling water tank; the laser ignition system is used for non-contact ignition of aluminum powder. A burner used to generate an aluminum powder premixed flame based on the ignited aluminum powder; The multispectral extinction and PIV diagnostic system includes a quasi-continuous laser, a laser shaping lens system, a broadband stroboscopic LED light source, a three-way filter, a color high-speed camera, and an imaging computer; the imaging computer is configured to perform the steps in the above embodiments.

[0062] For example, the system can be divided into an aluminum powder supply system, a laser ignition system, a burner, and a multispectral extinction and PIV diagnostic system. The aluminum powder supply system includes aluminum powder 4, a stepper motor-driven piston 5, a vibration device 6, and an aluminum powder supply device housing 7. The laser ignition system includes a carbon dioxide laser power supply 8, a carbon dioxide laser tube 9, a corner lens 10, and a cooling water tank 11. The burner 1 is used to generate an aluminum powder premixed flame based on the ignited aluminum powder. The multispectral extinction and PIV diagnostic system includes a 30W quasi-continuous laser (455 nm) 2, a laser shaping lens system 3, a high-power broadband stroboscopic LED light source 12, a quartz protective screen 13, a three-way filter 14, a microscope lens 15, a color high-speed camera 16, and an imaging computer 17.

[0063] I. The aluminum powder supply system and burner are responsible for providing a stable and quantitatively controllable combustion environment, forming the foundation of the entire experiment. Burner 1 is the physical carrier of the flame, designed as a nozzle with a flame-stabilizing structure to guide the premixed aluminum powder 4 and oxidant to the outlet to form a stable Bunsen burner flame. Aluminum powder 4 is high-purity spherical aluminum powder with a specific particle size distribution (e.g., 2-4 μm, etc., without limitation). Under the action of stepper motor-driven piston 5, it is transported to burner 1 through oxygen entrainment to form a premixed flame. Stepper motor-driven piston 5 serves as a precision conveying device for aluminum powder 4. The stepper motor-driven piston 5 controls the upward speed, enabling quantitative adjustment of the aluminum powder supply rate and ensuring a constant fuel concentration during the experiment. Vibration device 6 serves as a high-frequency vibration source to overcome the van der Waals forces and electrostatic attraction between the micron-sized aluminum powder 4, preventing the aluminum powder from agglomerating within the supply device and ensuring that the powder enters the airflow in a discrete state. The aluminum powder supply device housing 7 is a pressure-bearing and sealed container that can protect the internal mechanical structure and serves as a premixing chamber to initially mix the delivered aluminum powder with the carrier gas (oxygen / nitrogen).

[0064] II. The laser ignition system provides non-contact high-energy input, avoiding interference with the flow field caused by traditional electric sparks. The carbon dioxide laser power supply 8 provides controlled electrical energy to the carbon dioxide laser tube 9, supporting power adjustment to match different ignition energy requirements. Powered by the carbon dioxide laser power supply 8, the carbon dioxide laser tube 9 generates a 10.6μm wavelength far-infrared laser. Utilizing the absorption characteristics of aluminum powder 4 at this wavelength, efficient and rapid non-contact ignition is achieved. The corner mirror 10 can be used to change the propagation direction of the laser output from the carbon dioxide laser tube 9, precisely guiding the beam emitted by the laser tube to the ignition area at the burner 1 outlet. The cooling water tank 11 is a circulating water cooling system responsible for removing the heat generated by the carbon dioxide laser tube 9 during operation, maintaining long-term stability of the laser output power, and preventing frequency shift due to overheating.

[0065] III. The multispectral extinction and PIV diagnostic system acquires multidimensional information through the time-series coordination of different light sources and sensors. A 30W quasi-continuous laser (455 nm) 2 serves as the illumination source for PIV diagnostics, providing point-like laser light. The laser shaping lens system 3 converts the point-like laser beam generated by the 30W quasi-continuous laser (455 nm) 2 into a sheet-like light beam approximately 1 mm thick, used to segment the flame formed by the burner 1. Utilizing the different scattering characteristics of aluminum and alumina particles for the laser, it accurately locates the flame front while simultaneously measuring flow velocity. A high-power broadband stroboscopic LED light source 12 serves as the background light source for the multispectral extinction method. It possesses broadband (white) characteristics and provides background light intensity through high-frequency stroboscopic synchronization with the color high-speed camera 16. This intensity is used to calculate transmittance, and the local flame transmittance is calculated using Abel inversion. A quartz protective screen 13 is installed between the burner 1 and the three-way filter 14 to prevent alumina smoke and high-temperature heat radiation from combustion from directly damaging the precision lens, while ensuring optical transmittance. The three-way filter 14 is the core beam-splitting element. This filter has three specific narrow-bandpass windows (bandwidths of 446-468nm, 520-540nm, and 614-642nm, respectively), corresponding to the R, G, and B channels of the color camera. It decomposes the broadband LED light into three specific characteristic wavelengths, thus achieving multispectral acquisition with a single camera. The microscope lens 15, as an optical magnification component, provides high spatial resolution and captures small-sized aluminum powder flames. The high-speed color camera 16, as an image acquisition terminal, can use an internal Bayer filter in conjunction with the external three-way filter to simultaneously acquire extinction projections of different wavelengths, indirectly obtaining the absorptivity of condensation in the aluminum powder flame relative to different wavelengths of radiation. Simultaneously, its high frame rate supports the multi-state looping temporal capture required for the extinction method. The imaging computer 17 is responsible for real-time recording of the images captured by the high-speed color camera.

[0066] In this system, a quasi-continuous laser and a high-power broadband stroboscopic LED light source are alternately triggered within a microsecond time sequence. A single high-speed color camera equipped with a three-pass filter sequentially captures the scattering signal of aluminum particles (i.e., particle scattering image), multispectral extinction projection (i.e., particle scattering image), and the flame self-luminous background (i.e., flame self-luminous image). Subsequently, physical-level background subtraction is performed using the flame self-luminous image to eliminate high-temperature radiation interference. Combined with the inverse Abel transform (onion model), the two-dimensional projection is converted into a radial local extinction coefficient. Finally, based on the significant differences in optical properties (such as extinction slope and imaginary part of refractive index) between unburned aluminum particles and generated nanoscale alumina smoke at different wavelengths, a definite decoupling reconstruction of the flow field velocity vector, particle phase space distribution, and particle size evolution law is achieved.

[0067] Therefore, this application has the following beneficial effects: 1. Achieved synchronous reconstruction of combustion dynamics flow field and combustion structure. Traditional methods often focus on the static capture of thermodynamic parameters (such as temperature). However, due to the extremely high brightness of aluminum powder flames and the rapid movement of particles, it is difficult to extract their displacement vectors against a strong radiation background, resulting in a lack of spatial correlation between the velocity field and the combustion reaction zone. This application introduces a 455 nm quasi-continuous laser in conjunction with a sheet-like light shaping system (the sheet-like light shaping system includes a laser shaping lens system 3). Since the 455 nm band is in the range of low self-luminous radiation intensity of aluminum powder flames, using a high-power quasi-continuous laser as an illumination source allows a high-speed color camera to capture particle scattering images with a high signal-to-noise ratio. By performing cross-correlation (PIV) operations on consecutive frames, the transient velocity vector field of particles during combustion can be obtained. This is combined with flame front identification within the same time sequence.

[0068] 2. Possesses the ability to decouple and reconstruct parameters of micro- and nano-scale condensed products (alumina). In aluminum powder flames, unburned aluminum particles are mixed with the generated alumina fumes, and their optical contributions are indistinguishable at a single wavelength. This makes it impossible to independently obtain the particle size and number density characteristics of alumina using existing technologies, hindering the assessment of its erosion effect on the nozzle. This application uses a high-power broadband stroboscopic LED light source combined with a three-pass filter to obtain the local extinction coefficients at R / G / B wavelengths. Utilizing the significant spectral selectivity exhibited by alumina fumes (nanometer to submicron scale), and using aluminum powder with known initial particle size and spatial distribution as constraints, the radial local optical thickness is obtained through inverse Abel transform, thus separating the contribution of alumina from the total signal. This application can invert the local number density distribution and median particle size of alumina particles. This result provides core experimental data support for accurately modeling the internal radiation transmission environment of engines and predicting the two-phase flow erosion rate of nozzle walls.

[0069] 3. Multi-time multiplexing technology By coordinating laser, broadband stroboscopic LED light source, and camera shutter at the microsecond level, three types of data—flame self-luminescence, white background light + flame self-luminescence, and PIV laser scattering + flame self-luminescence—are acquired alternately in an extremely short time, thus solving the signal coupling problem at the underlying physical level.

[0070] 4. Single-camera multi-wavelength integration By using a Bayer filter from a color camera in combination with a custom three-way filter, simultaneous acquisition of three bands by a single device was achieved, ensuring geometric consistency during Abel inversion.

[0071] 5. Simplification of the premixed Bunsen lamp model By using aluminum particles with known initial particle size distribution and spatial distribution information as constraints, and combining multispectral slope analysis, quantitative reconstruction of the optical thickness of alumina extracted from aluminum powder flames was achieved.

[0072] Corresponding to the above method, this application also provides a device for determining the two-phase flow of aluminum particle combustion, such as... Figure 5 As shown, the device includes: The acquisition module 41 is used to alternately acquire at least three types of images according to a preset time sequence control parameter set under the stable combustion state of aluminum powder flame; the images include flame self-luminous images without active illumination, multispectral extinction images under broadband active illumination, and particle scattering images under laser sheet illumination. Subtraction module 42 is used to perform pixel-level background subtraction on multispectral extinction image and particle scattering image respectively using flame self-luminescence image; Calculation module 43 is used to perform cross-correlation calculations on the particle scattering image after background subtraction to obtain the velocity vector field characterizing the dynamic properties of the gas phase and particle phase and the spatial distribution information of aluminum powder particles; based on the multispectral extinction image after background subtraction, the local extinction coefficient distribution of the radial section of the flame is obtained; The generation module 44 is used to obtain the two-phase flow parameters of the condensed product alumina based on the preset initial particle size distribution, spatial distribution information and local extinction coefficient distribution of aluminum powder; the two-phase flow parameters include volume fraction and particle size distribution.

[0073] The functions of each functional unit in the aluminum particle combustion two-phase flow determination device provided in the above embodiments of this application can be realized through the above method steps. Therefore, the specific working process and beneficial effects of each unit in the aluminum particle combustion two-phase flow determination device provided in the embodiments of this application will not be repeated here.

[0074] This application also provides an electronic device, such as... Figure 6As shown, it includes a processor 510, a communication interface 520, a memory 530, and a communication bus 540, wherein the processor 510, the communication interface 520, and the memory 530 communicate with each other through the communication bus 540.

[0075] Memory 530 is used to store computer programs; The processor 510 performs the above steps when executing the program stored in the memory 530.

[0076] The communication bus mentioned above can be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. This communication bus can be divided into address bus, data bus, control bus, etc. For ease of illustration, only one thick line is used to represent it in the diagram, but this does not mean that there is only one bus or one type of bus.

[0077] The communication interface is used for communication between the aforementioned electronic devices and other devices.

[0078] The memory may include random access memory (RAM) or non-volatile memory (NVM), such as at least one disk storage device. Optionally, the memory may also be at least one storage device located remotely from the aforementioned processor.

[0079] The processors mentioned above can be general-purpose processors, including central processing units (CPUs), network processors (NPs), etc.; they can also be digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components.

[0080] The implementation methods and beneficial effects of the various components of the electronic device in the above embodiments for solving the problem can be found in [reference needed]. Figure 1 The steps in the illustrated embodiments are used to implement the electronic device. Therefore, the specific working process and beneficial effects of the electronic device provided in this application will not be repeated here.

[0081] In another embodiment provided in this application, a computer-readable storage medium is also provided, which stores instructions that, when executed on a computer, cause the computer to perform the aluminum particle combustion two-phase flow determination method described in any of the above embodiments.

[0082] In another embodiment provided in this application, a computer program product containing instructions is also provided, which, when run on a computer, causes the computer to execute the aluminum particle combustion two-phase flow determination method described in any of the above embodiments.

[0083] Those skilled in the art will understand that the embodiments in this application can be provided as methods, systems, or computer program products. Therefore, the embodiments in this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the embodiments in this application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0084] This application describes embodiments of methods, apparatus (systems), and computer program products according to embodiments of this application with reference to flowchart illustrations and / or block diagrams. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0085] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0086] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0087] Although preferred embodiments have been described in this application, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the embodiments of this application.

[0088] Obviously, those skilled in the art can make various modifications and variations to the embodiments of this application without departing from the spirit and scope of the embodiments of this application. Therefore, if these modifications and variations to the embodiments of this application fall within the scope of the claims in this application and their equivalents, then this application also intends to include these modifications and variations.

Claims

1. A method for determining the two-phase flow of aluminum particle combustion, characterized in that, include: Under the stable combustion state of aluminum powder flame, at least three types of images are alternately acquired according to a preset time sequence control parameter set; the images include flame self-luminous images without active illumination, multispectral extinction images under broadband active illumination, and particle scattering images under laser sheet illumination. Using the flame self-luminous image, pixel-level background subtraction is performed on the multispectral extinction image and the particle scattering image, respectively. Cross-correlation calculations were performed on the particle scattering image after background subtraction to obtain the velocity vector field characterizing the dynamic properties of the gas phase and the particle phase, as well as the spatial distribution information of aluminum powder particles; based on the multispectral extinction image after background subtraction, the local extinction coefficient distribution of the flame radial section was obtained. Based on the preset initial particle size distribution of aluminum powder, the spatial distribution information, and the local extinction coefficient distribution, the two-phase flow parameters of the condensed product alumina are obtained; these two-phase flow parameters include volume fraction and particle size distribution.

2. The method as described in claim 1, characterized in that, The timing control parameter set includes: Pulse on-time, pulse width, and off-time of quasi-continuous lasers; pulse on-time, pulse width, and off-time of broadband stroboscopic LED light sources; exposure start time and exposure duration of color high-speed cameras; The timing control parameter set is configured to control the color high-speed camera to sequentially acquire images in the following three states within a continuous time window: First state: The quasi-continuous laser is off, and the broadband strobe LED light source is off; Second state: The quasi-continuous laser is off, and the broadband strobe LED light source is on; Third state: The quasi-continuous laser is turned on, and the broadband strobe LED light source is turned off.

3. The method as described in claim 1 or 2, characterized in that, The multispectral extinction image was obtained through the following method: A color high-speed camera with R / G / B three channels is used, and a three-pass filter is installed in conjunction with it. The three-pass filter has three narrow bandpass windows corresponding to the R, G, and B channels of the color high-speed camera, respectively.

4. The method as described in claim 1, characterized in that, Based on the multispectral extinction image after background subtraction, the local extinction coefficient distribution of the radial cross-section of the flame is obtained, including: Based on the multispectral extinction image after background subtraction, calculate the optical thickness at at least two different wavelengths; By using the inverse Abel transform, the optical thickness at each wavelength is inverted into the local extinction coefficient distribution of the radial cross section of the flame.

5. The method as described in claim 1, characterized in that, The process of obtaining the two-phase flow parameters of the condensed product alumina based on the preset initial particle size distribution of aluminum powder, the spatial distribution information, and the local extinction coefficient distribution includes: Based on the multispectral extinction image after background subtraction, the projection optical thickness of each pixel at at least two different wavelengths is obtained. Based on the axisymmetric structure of the flame, the flame cross section is discretized according to the projected optical thickness of each pixel. The projected optical thickness at each wavelength is inverted into the local extinction coefficient distribution of the radial cross section of the flame through the inverse Abel transform. Constrained by the preset initial particle size distribution of aluminum powder and the spatial distribution information of the aluminum powder particles, the number density distribution and equivalent particle size distribution of alumina particles on the radial cross section of the flame are obtained by fitting multispectral extinction data using the local extinction coefficient distribution at at least two different wavelengths.

6. The method as described in claim 1, characterized in that, The laser sheet light is generated by a quasi-continuous laser with a wavelength of 455nm in conjunction with a laser shaping lens system; the broadband active illumination is provided by a broadband strobe LED light source.

7. The method as described in claim 1, characterized in that, The velocity vector field of the particle motion is used to characterize the transient flow field dynamics during the combustion process of aluminum particles and is synchronously correlated with the flame front space.

8. A system for determining the two-phase flow of aluminum particle combustion, characterized in that, The system includes: An aluminum powder supply system includes aluminum powder, a stepper motor-driven piston, a vibration device, and an aluminum powder supply device housing; the aluminum powder supply system is used to provide stable and controllable aluminum powder fuel. A laser ignition system includes a carbon dioxide laser power supply, a carbon dioxide laser tube, a corner mirror, and a cooling water tank; the laser ignition system is used for non-contact ignition of aluminum powder. A burner used to generate an aluminum powder premixed flame based on the ignited aluminum powder; A multispectral extinction and PIV diagnostic system includes a quasi-continuous laser, a laser shaping lens system, a broadband stroboscopic LED light source, a three-way filter, a color high-speed camera, and an imaging computer; said imaging computer is configured to perform the steps of the method according to any one of claims 1 to 6.

9. A device for determining the two-phase flow of aluminum particle combustion, characterized in that, The device includes: The acquisition module is used to alternately acquire at least three types of images under the stable combustion state of aluminum powder flame according to a preset time sequence control parameter set; the images include flame self-luminous images without active illumination, multispectral extinction images under broadband active illumination, and particle scattering images under laser sheet illumination. The background subtraction module is used to perform pixel-level background subtraction on the multispectral extinction image and the particle scattering image respectively using the flame self-luminous image; The calculation module is used to perform cross-correlation calculations on the particle scattering image after background subtraction to obtain the velocity vector field characterizing the dynamic properties of the gas phase and the particle phase, as well as the spatial distribution information of aluminum powder particles; based on the multispectral extinction image after background subtraction, the local extinction coefficient distribution of the flame radial section is obtained. The generation module is used to obtain the two-phase flow parameters of the condensed product alumina based on the preset initial particle size distribution of aluminum powder, the spatial distribution information, and the local extinction coefficient distribution; the two-phase flow parameters include volume fraction and particle size distribution.

10. An electronic device, characterized in that, The electronic device includes a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus; Memory, used to store computer programs; A processor, when executing a program stored in memory, implements the method of any one of claims 1-7.

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