Particle size and mixing ratio measurement method and device, electronic equipment and storage medium

Abstract

The present application relates to a kind of particle size and mixing ratio measurement method, device, electronic equipment and storage medium, comprising: by extinction method measurement to the two-phase system mixed with first solid particles and second solid particles obtains corresponding experimental extinction spectrum, first solid particles and second solid particles are two different types of solid particles.By calculating the extinction coefficient of first solid particles and second solid particles under the action of light wave is obtained.By calculating the albedo of first solid particles and second solid particles, and judging whether corresponding photon is scattered.If photon is scattered, the scattering angle when photon is scattered and the random free step length between adjacent two scattering of photon are obtained.According to the direction of photon exit, the corresponding theoretical extinction spectrum of the two-phase system mixed with first solid particles and second solid particles is obtained by calculation.Based on experimental extinction spectrum and theoretical extinction spectrum, the particle size and mixing number ratio of solid particles are obtained.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of light scattering particle detection, in particular to a particle size and mixing ratio measurement method and device, electronic equipment and storage medium. BACKGROUND

[0002] It is a very important work to objectively and truly reflect the particle size and concentration of discrete state particles. Measuring the particle size and concentration of discrete state particles has wide application background in the fields of power, chemical industry, medicine, environmental protection, water conservancy, materials, etc. The particle measurement method has developed from the initial offline measurement method such as microscope method to the current online real-time monitoring methods such as dynamic image method, light scattering method and ultrasonic method. The light scattering method has rapidly developed due to its low equipment cost, simple device, easy implementation and fast measurement.

[0003] The extinction method is one of the light scattering particle measurement technologies, which has the advantages of simple principle, convenient operation, wide measurement range, accurate and fast measurement results, and can be widely applied to particle size and concentration analysis of suspended dust, flame dust, wear particles, wet steam, emulsion, etc. The particles in nature are various, and in some cases they are mixed with each other. The extinction characteristics of these mixed particle systems are different from those of single particle systems, and the type and proportion of mixed particles will affect their extinction spectrum. The traditional light scattering modeling and algorithm can only be applied to single particle systems, and cannot meet the testing requirements and precision in various applications.

[0004] In summary, the traditional light scattering particle measurement method is easily affected by mixed particles, and has poor measurement accuracy in particle measurement. SUMMARY

[0005] Therefore, it is necessary to provide a particle size and mixing ratio measurement method and device, electronic equipment and storage medium capable of measuring mixed particles and having good measurement accuracy.

[0006] The present application provides a particle size and mixing ratio measurement method, which comprises:

[0007] The extinction method is used to measure a two-phase system mixed with first solid particles and second solid particles to obtain a corresponding experimental extinction spectrum, wherein the first solid particles and the second solid particles are two different types of solid particles;

[0008] The extinction coefficients of the first solid particles and the second solid particles under the action of light waves are calculated;

[0009] The albedos of the first solid particles and the second solid particles are calculated, and it is judged whether the corresponding photons are scattered or not. If the corresponding photons are scattered,

[0010] acquire a scattering angle when the photon scatters and a random free step length between two adjacent scattering of the photon;

[0011] determine an exit direction of the exit photon based on the scattering angle when the photon scatters, and acquire a theoretical extinction spectrum corresponding to the two-phase system mixed with the first solid particles and the second solid particles by calculation;

[0012] acquire an objective function based on the experimental extinction spectrum and the theoretical extinction spectrum, the objective function being used to solve the particle size and the mixing number ratio of the first solid particles and the second solid particles.

[0013] In one of the embodiments, the acquiring of the corresponding experimental extinction spectrum by measuring the two-phase system mixed with the first solid particles and the second solid particles by the extinction method includes:

[0014] when the measurement area does not contain the solid particles, receiving the laser from the laser emitter by the receiver in the measurement area and acquiring a first receiving signal;

[0015] when the measurement area contains the solid particles, receiving the laser from the laser emitter by the receiver in the measurement area and acquiring a second receiving signal;

[0016] acquiring a signal intensity spectrum of multiple wavelengths of the laser based on the first receiving signal and the second receiving signal to acquire the experimental extinction spectrum corresponding to different wavelengths;

[0017] wherein, the first receiving signal is the laser signal corresponding to the measurement area without the solid particles, and the second receiving signal is the laser signal corresponding to the measurement area containing the solid particles.

[0018] In one of the embodiments, the acquiring of the extinction coefficient of the first solid particles and the second solid particles under the action of the light wave by calculation includes:

[0019] the Monte Carlo method is used to simulate the light scattering process, and the incident light in the scattering process is discretized into multiple discontinuous photons to establish a probability model;

[0020] acquiring a movement direction of the photon based on the interaction between the photon and the particle, the movement direction being used to describe the absorption and scattering process of the photon after the interaction with the solid particles.

[0021] In one of the embodiments, the acquiring of the extinction coefficient of the first solid particles and the second solid particles under the action of the light wave by calculation includes:

[0022] When the photon collides with the solid particle, a random number generated by a linear congruential method is used to determine the type of the solid particle;

[0023] When the solid particle has the absorption and scattering process, the extinction coefficient is obtained by calculation.

[0024] In one embodiment, the calculation of the albedo of the first and second solid particles and the determination of whether the corresponding photon is scattered include:

[0025] Based on the extinction coefficient, the albedo of the corresponding scattering cross section and extinction cross section is obtained, and the albedo is the ratio of the scattering cross section and the extinction cross section.

[0026] If the random number is greater than the albedo, the photon is absorbed, and if the random number is less than or equal to the albedo, the photon is scattered.

[0027] In one embodiment, the scattering angle when the photon is scattered and the random free step length between two adjacent scattering of the photon are obtained, including:

[0028] After the photon collides with the solid particle and is scattered, the scattering angle is determined by the Henyey-Greenstein phase function.

[0029] Based on the scattering angle and the scattering direction of the scattered photon, the trajectory of the photon is obtained, and the random free step length is obtained by calculation.

[0030] In one embodiment, the determination of the scattering direction of the outgoing photon based on the scattering angle when the photon is scattered, and the calculation of the theoretical extinction spectrum of the two-phase system mixed with the first and second solid particles include:

[0031] Based on the coordinates of the photon in the measurement region and the random free step length between adjacent scattering, the coordinates of the first scattering of the photon are obtained.

[0032] According to the collision type of the photon and the solid particle, the scattering angle and the random free step length, the transmission process of the photon in the solid particle is determined, if the photon is absorbed, the transmission process is stopped, if the photon is scattered, the transmission process is continued.

[0033] The number of photons reaching the receiver is obtained by statistics, and the theoretical extinction spectrum is obtained based on the number of photons.

[0034] The present application also provides a particle size and mixing ratio measuring device, which comprises:

[0035] The measuring module is configured to acquire a corresponding experimental extinction spectrum by performing an extinction method measurement on a two-phase system mixed with the first solid particles and the second solid particles, the first solid particles and the second solid particles being two different types of solid particles.

[0036] The first acquiring module is configured to acquire extinction coefficients of the first solid particles and the second solid particles under the action of light waves by calculation.

[0037] The judging module is configured to acquire albedos of the first solid particles and the second solid particles by calculation, and to judge whether a corresponding photon is scattered; if the corresponding photon is scattered,

[0038] The second acquiring module is configured to acquire a scattering angle when the photon is scattered and a random free step length between two adjacent scattering of the photon.

[0039] The third acquiring module is configured to determine an exit direction of an exit photon based on the scattering angle when the photon is scattered, and to acquire a corresponding theoretical extinction spectrum of the two-phase system mixed with the first solid particles and the second solid particles by calculation.

[0040] The function constructing module is configured to acquire an objective function based on the experimental extinction spectrum and the theoretical extinction spectrum, the objective function being used to solve particle diameters and a mixing number ratio of the first solid particles and the second solid particles.

[0041] The present application further provides an electronic device comprising a memory and a processor, the memory storing a computer program, and the processor implementing the particle diameter and mixing ratio measurement method according to any one of the above when executing the computer program.

[0042] The present application further provides a computer storage medium storing a computer program, and the computer program implementing the particle diameter and mixing ratio measurement method according to any one of the above when executed by a processor.

[0043] The particle size and mixing ratio measurement method, device, electronic equipment and storage medium measure the extinction spectrum of the two-phase system mixed with two different types of solid particles, and then calculate the extinction coefficients of the two different types of solid particles under the action of light waves. Then, the albedos of the two different types of solid particles are calculated, and it is determined whether the corresponding photons are scattered. If the corresponding photons are scattered, the scattering angle when the photons are scattered and the random free step length between the adjacent two scattering of the photons are obtained. The outgoing direction of the outgoing photons is counted, and the theoretical extinction spectrum of the two-phase system mixed with two types of solid particles is calculated. Finally, the objective function is obtained based on the experimental extinction spectrum and the theoretical extinction spectrum, and the particle size and mixing number ratio of the two types of particles are solved by the objective function. The method considers the extinction spectrum prediction of the mixed particle system with two different particles, and solves the particle size and mixing ratio of the mixed particle system by combining the objective function constructed by the extinction spectrum. It is no longer limited to the measurement of a single solid particle, and can measure mixed particles, reduce the interference of other solid particles in the measurement of solid particles, and thus improve the accuracy of particle measurement. BRIEF DESCRIPTION OF DRAWINGS

[0044] In order to more clearly illustrate the technical solutions in the present application or prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0045] Figure 1 One of the particle size and mixing ratio measurement method flowchart provided by the present application;

[0046] Figure 2 The second particle size and mixing ratio measurement method flowchart provided by the present application;

[0047] Figure 3 The third particle size and mixing ratio measurement method flowchart provided by the present application;

[0048] Figure 4 The fourth particle size and mixing ratio measurement method flowchart provided by the present application;

[0049] Figure 5 The fifth particle size and mixing ratio measurement method flowchart provided by the present application;

[0050] Figure 6 The sixth particle size and mixing ratio measurement method flowchart provided by the present application;

[0051] Figure 7A seventh flowchart of a particle size and mixing ratio measurement method according to an embodiment of the present application;

[0052] Figure 8 A measurement principle diagram of a particle size and mixing ratio measurement method according to an embodiment of the present application;

[0053] Figure 9 A photon transport direction statistical diagram of a particle size and mixing ratio measurement method according to an embodiment of the present application;

[0054] Figure 10 An extinction spectrum diagram of a particle size and mixing ratio measurement method according to an embodiment of the present application;

[0055] Figure 11 A structure diagram of a particle size and mixing ratio measurement device according to an embodiment of the present application;

[0056] Figure 12 An internal structure diagram of a computer device according to an embodiment of the present application. DETAILED DESCRIPTION

[0057] In order to make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the following will clearly and completely explain the technical solutions of the embodiments of the present application with reference to the drawings of the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present application.

[0058] The following will be described with reference to the drawings. Figures 1-12 The particle size and mixing ratio measurement method, device, electronic device and storage medium of the present application are described.

[0059] As shown in the drawings, in one embodiment, a particle size and mixing ratio measurement method comprises the following steps: Figure 1

[0060] In step S110, an extinction value is obtained by measuring a two-phase system mixed with first solid particles and second solid particles by an extinction method, the first solid particles and the second solid particles being two different types of solid particles.

[0061] Specifically, the server obtains an experimental extinction spectrum by measuring a two-phase system mixed with two different types of solid particles in a measurement area by an extinction method.

[0062] In step S120, an extinction coefficient of the first solid particles and the second solid particles under the action of light waves is obtained by calculation.

[0063] ​Specifically, the server obtains the extinction coefficients of the first solid particles and the second solid particles under the action of light waves by calculation, and the first solid particles and the second solid particles are two different types of solid particles in the two-phase system in step S110.

[0064] wherein the extinction coefficient q ext is calculated by the following formula:

[0065]

[0066] wherein,

[0067] wherein,

[0068] wherein, J l+1 / 2 and H l+1 / 2 (α) are the half-integer order Bessel function and the first Hankel function respectively, and α is the dimensionless particle size, α = 2πR / λ. When the particle has an absorption characteristic, the imaginary part of the particle refractive index m = n - iη is not zero, and when the particle has no absorption to light, the imaginary part of the refractive index η is zero, at this time the absorption coefficient q abs is equal to zero, that is, the extinction coefficient is equal to the scattering coefficient, q ext = q sca . For different particle types, the particle size and the refractive index are different, and the corresponding extinction coefficients are also different, and the extinction coefficients of the two particles are denoted as q ext，1 and q ext，2 .

[0069] In step S130, the albedo of the first solid particles and the second solid particles is obtained by calculation, and it is judged whether the corresponding photons are scattered.

[0070] Specifically, the server defines the ratio of the scattering cross section to the extinction cross section as the albedo a according to the extinction coefficient calculated in step S120, so as to judge the possible events after the photons collide with the particles:

[0071] a = q sca / q ext .

[0072] The random number ε2 generated by the linear congruential method is compared with the size of the albedo, and the albedo is selected according to the particle type judged in the front, at this time, the albedo of polystyrene is a1 = q ext，1 / q sca，1 , and the albedo of high-density glass is a2 = q ext，2 / q sca，2 :

[0073]

[0074] If the photon is absorbed, it will not be received by the receiver, and if scattering occurs, the scattering angle and the scattering free path of the scattered photon need to be calculated.

[0075] In step S140, if the corresponding photon is scattered, the scattering angle when the photon is scattered and the random free step length between adjacent scattering of the photon are obtained.

[0076] Specifically, when the photon is scattered, the server obtains the scattering angle when the photon is scattered and the random free step length between adjacent scattering of the photon.

[0077] Wherein, after the photon collides with the particle and is scattered, the scattering angle is determined by the Henyey-Greenstein phase function, and the sampling of the scattering angle θ0 is represented as:

[0078]

[0079] In the formula, is a random number in the range of [0, 1] generated by the linear congruential method, and g is an asymmetric factor which can be calculated by the Mie scattering theory. After determining the scattering direction of the photon, the motion trajectory of the photon is further tracked, and the random free step length l between adjacent scattering of the photon can be represented as:

[0080]

[0081] In the formula, ε l is a random number in the range of [0, 1] generated by the linear congruential method, and the turbidity τ can be determined by the extinction coefficient and the particle coefficient concentration.

[0082] In step S150, the exit direction of the exit photon is determined based on the scattering angle when the photon is scattered, and the theoretical extinction spectrum corresponding to the two-phase system mixed with the first solid particles and the second solid particles is obtained by calculation.

[0083] Specifically, the server performs exit direction statistics on the exit photon, takes the center point of the emitter as the origin, and sets the initial exit coordinates of the photon as (x0, y0):

[0084]

[0085] In the formula, ε3 is a random number in the range of [0, 1] generated by the linear congruential method, and at this time, the scattering direction of the photon θ1= θ0, and the incident light is parallel light, so θ0= 0. Combined with the coordinates of the photon entering the sample pool and the random free step length between adjacent scattering, the coordinates (x1, y1) of the first scattering of the photon can be represented as:

[0086]

[0087] The transmission process of the photon in the particle medium is obtained by judging the collision type, the scattering angle and the scattering random free step calculation formula. If the photon is absorbed, the transmission process is terminated, otherwise, the process continues. The photon scattering direction of the photon at the n-th scattering is θ n = θ n-1 + θ0, and the position of the particle of the n-th collision can be expressed as:

[0088]

[0089] The theoretical extinction spectrum can be calculated by counting the number of photons finally reaching the receiver N.

[0090] E = ln (I / I0) = ln (N / N set ).

[0091] In the formula, N is the total number of received transmitted photons, N set is the set number of photons, and the sample capacity of the photons is generally 100,000 to 1,000,000.

[0092] In step S160, a target function is obtained based on the experimental extinction spectrum and the theoretical extinction spectrum, and the target function is used to solve the particle size and the mixing number ratio of the first solid particle and the second solid particle.

[0093] Specifically, the server constructs a target function according to the experimental extinction spectrum obtained in step S110 and the theoretical extinction spectrum calculated in step S150:

[0094]

[0095] Where λ i is a known wavelength, R1, R2 and φ are undetermined parameters, E m is the experimental extinction spectrum, and E is the theoretical extinction spectrum. The particle size and the mixing ratio are obtained by optimizing the target function J, and the optimization process can be realized by the Particle Swarm Optimization (PSO) algorithm, and other optimal algorithms are not excluded.

[0096] The particle size and mixing ratio measurement method measures the extinction spectrum of the two-phase system mixed with the two types of solid particles by the extinction method, and then calculates the extinction coefficients of the two types of solid particles under the action of light waves. Then, the albedos of the two types of solid particles are calculated to determine whether the corresponding photons are scattered. If the corresponding photons are scattered, the scattering angle of the photons when the scattering occurs and the random free step length between the adjacent two scattering of the photons are obtained. The outgoing direction of the outgoing photons is counted, and the theoretical extinction spectrum of the two-phase system mixed with the two types of solid particles is calculated. Finally, the objective function is obtained based on the experimental extinction spectrum and the theoretical extinction spectrum, and the particle size and mixing ratio of the two types of particles are solved by the objective function. The method considers the extinction spectrum prediction of the mixed particle system with two different particles, and solves the particle size and mixing ratio of the mixed particle system by combining the objective function constructed by the extinction spectrum. The method is no longer limited to the measurement of a single solid particle, but can measure mixed particles, reduces the interference of other solid particles in the measurement of the solid particles, and thus improves the accuracy of the particle measurement.

[0097] As shown in Figure 2 In one embodiment, the particle size and mixing ratio measurement method provided by the application measures the experimental extinction spectrum of the two-phase system mixed with the first solid particles and the second solid particles by the extinction method, including the following steps:

[0098] In step S112, when the measurement area does not contain solid particles, the receiver receives the laser from the laser emitter in the measurement area, and the first receiving signal is obtained.

[0099] Specifically, when the measurement area does not contain solid particles, the server receives the laser from the laser emitter in the measurement area through the receiver, and obtains the signal corresponding to the measurement area without solid particles.

[0100] In step S114, when the measurement area contains solid particles, the receiver receives the laser from the laser emitter in the measurement area, and the second receiving signal is obtained.

[0101] Specifically, when the measurement area contains solid particles, the server receives the laser from the laser emitter in the measurement area through the receiver, and obtains the signal corresponding to the measurement area containing solid particles.

[0102] In step S116, the signal intensity spectrum of the multiple wavelengths of the laser is obtained based on the first receiving signal and the second receiving signal, so as to obtain the experimental extinction spectrum corresponding to different wavelengths.

[0103] Specifically, the server obtains the signal intensity spectrum of different wavelengths corresponding to the measurement region without or with the solid particles based on the first received signal and the second received signal obtained in steps S112 and S114, and obtains the experimental extinction spectrum corresponding to different wavelengths.

[0104] As shown in Figure 3 In one embodiment, the particle size and mixing ratio measurement method provided by the application obtains the extinction coefficients of the first solid particles and the second solid particles under the action of light waves by calculation, and includes the following steps before the calculation:

[0105] In step S310, the Monte Carlo method is used to simulate the light scattering process, and the incident light in the scattering process is discretized into a plurality of non-continuous photons to establish a probability model.

[0106] Specifically, the server uses the Monte Carlo method to simulate the light scattering process, and discretizes the incident light in the scattering process into a plurality of non-continuous photons to establish a corresponding probability model.

[0107] In step S320, the motion direction of the photon is obtained based on the interaction between the photon and the solid particles, and the motion direction is used to describe the absorption and scattering processes of the photon after the interaction with the solid particles.

[0108] Specifically, the server obtains the motion direction of the photon based on the interaction between the photon and the solid particles, and describes the absorption and scattering processes of the photon after the interaction with the solid particles through the motion direction.

[0109] As shown in Figure 4 In one embodiment, the particle size and mixing ratio measurement method provided by the application obtains the extinction coefficients of the first solid particles and the second solid particles under the action of light waves by calculation, and includes the following steps before the calculation:

[0110] In step S122, when the photon collides with the solid particles, the type of the solid particles is determined by the random number generated by the linear congruential method.

[0111] Specifically, when the photon collides with the solid particles, the type of the solid particles is determined by the random number generated by the linear congruential method.

[0112] In step S124, the extinction coefficient is calculated and obtained when the solid particles have the absorption and scattering processes.

[0113] Specifically, the corresponding extinction coefficient is calculated and obtained when the solid particles have the absorption and scattering processes.

[0114] As shown in Figure 5As shown in one embodiment, the particle size and mixing ratio measuring method provided by the present application comprises the following steps of:

[0115] In step S132, the albedo of the scattering cross section and the extinction cross section is obtained based on the extinction coefficient, and the albedo is the ratio of the scattering cross section and the extinction cross section.

[0116] Specifically, the server obtains the ratio between the albedo of the scattering cross section and the extinction cross section based on the extinction coefficient obtained above, i.e., the albedo.

[0117] In step S134, if the random number is greater than the albedo, the photon is absorbed, and if the random number is less than or equal to the albedo, the photon is scattered.

[0118] Specifically, if the random number is greater than the albedo obtained in step S132, it is determined that the photon is absorbed, and if the random number is less than or equal to the albedo, it is determined that the photon is scattered.

[0119] As shown in one embodiment, the particle size and mixing ratio measuring method provided by the present application comprises the following steps of: Figure 6 As shown in one embodiment, the particle size and mixing ratio measuring method provided by the present application comprises the following steps of:

[0120] In step S142, the scattering angle is determined by the Henyey-Greenstein phase function after the photon collides with the solid particle and is scattered.

[0121] Specifically, the server determines the corresponding scattering angle by the Henyey-Greenstein phase function after the photon collides with the solid particle and is scattered.

[0122] In step S144, the motion trajectory of the photon is obtained based on the scattering angle and the scattering direction after the photon is scattered, and the random free step is obtained by calculation.

[0123] Specifically, the server obtains the motion trajectory of the photon based on the scattering angle and the scattering direction after the photon is scattered, and calculates and obtains the corresponding random free step based on the motion trajectory.

[0124] As shown in one embodiment, the particle size and mixing ratio measuring method provided by the present application comprises the following steps of: Figure 7 As shown in one embodiment, the particle size and mixing ratio measuring method provided by the present application comprises the following steps of:

[0125] Step S152, based on the coordinates of the photons in the measurement region and the random free step length between adjacent scatterings, the coordinates of the first scattering of the photons are obtained.

[0126] Specifically, the server obtains the coordinates of the first scattering of the photons based on the coordinates of the photons in the measurement region and the random free step length between adjacent scatterings.

[0127] Step S154, the transmission process of the photons in the solid particles is judged according to the collision type of the photons and the solid particles, the scattering angle, and the random free step length, if the photons are absorbed, the transmission process is stopped, and if the photons are scattered, the transmission process is continued.

[0128] The collision type is two cases that the photons are absorbed or scattered after the collision of the photons and the solid particles.

[0129] Specifically, the server judges the transmission process of the photons in the solid particles through the collision type of the photons and the solid particles, the scattering angle, and the random free step length, if the photons are absorbed, the transmission process of the photons in the solid particles is stopped, and if the photons are scattered, the transmission process of the photons in the solid particles is continued.

[0130] Step S156, the number of photons reaching the receiver is obtained by statistics, and the theoretical extinction spectrum is obtained based on the number of photons.

[0131] Specifically, the server obtains the number of photons reaching the receiver by statistics, and obtains the theoretical extinction spectrum corresponding to the photons based on the number of photons.

[0132] In specific embodiments, the present application provides a particle size and mixing ratio measurement method, which introduces the Monte Carlo method into the extinction measurement of mixed particle systems, calculates the theoretical extinction spectrum, and combines the extinction spectrum measurement of the two-phase system of mixed particles and the optimization algorithm calculation. Figure 8 As shown, first, a parallel light is emitted by a laser emitter, and a sample cell is arranged as a measurement region at a distance S = 45 mm from the emitter, the sample cell has a thickness L = 10 mm, a receiver is arranged at a distance S = 45 mm from the sample cell, and the diameters of the emitter and the receiver are both d T = d R = 1 mm, and the emitter emits a wavelength of λ = 0.4-0.8 μm. When the measurement region does not contain particles, the laser is received by the receiver after transmitting through the measured region, and the received signal is I0, when the measurement region contains two types of particles, the radius of the polystyrene particles is R1, the radius of the high-density glass particles is R2, the number ratio of the high-density glass particles is the mixing ratio φ, and the volume concentration of the mixed particle system is C v = 2 × 10 -5, particle size and mixing ratio are to be measured, the signal received by the laser through the measured area is I. For visible light, the signal intensity spectrum of multiple wavelengths can be obtained, and the extinction spectrum ln [I0 / I] is obtained for different wavelengths.

[0133] Subsequently, the Monte Carlo method is used to simulate the scattering process, a large number of discrete photons are used to establish a probability model, the direction of the photons is counted through the interaction between the photons and the particles, the absorption and scattering processes after the interaction of the particles are described, the photons are emitted by the emitter into the sample cell, and if the photons collide with the particles, the random number ε1 generated by the linear congruential method is used to determine whether the particle type is polystyrene particles or high-density glass particles:

[0134]

[0135] When the particles have absorption and scattering processes, the extinction coefficient q of the particles under the action of light waves needs to be calculated ext , which is calculated by the following formula:

[0136]

[0137] In the formula,

[0138] wherein,

[0139] In the formula, J l+1 / 2 (α) and H l+1 / 2 (α) are the half-integer order Bessel function and the first type Hankel function, respectively, and α is the dimensionless particle size, α = 2πR / λ. When the particles have absorption characteristics, the imaginary part of the refractive index of the particles m = n - iη is not zero, and when the particles have no absorption to light, the imaginary part of the refractive index η is zero, and the absorption coefficient q abs is equal to zero, that is, the extinction coefficient is equal to the scattering coefficient, q ext = q sca . For different particle types, the particle size and the refractive index are different, and the corresponding extinction coefficients are different, and the extinction coefficients of the two particles are respectively denoted as q ext，1 and q ext，2 .

[0140] Then, according to the calculated extinction coefficient, the ratio of the scattering cross section to the extinction cross section is defined as the albedo a, so as to judge the possible events of the photons colliding with the particles:

[0141] a = q sca / q ext .

[0142] The random number ε2 generated by the linear congruential method is compared with the size of the albedo, and the albedo is selected according to the particle type judged in the front, at this time, the albedo of polystyrene is a1 = qext，1 / q sca，1 , the albedo of high-density glass is a2=q ext，2 / q sca，2 :

[0143]

[0144] If the photon is absorbed, it will not be received by the receiver, and if scattering occurs, the scattering angle and the scattering free path of the scattered photon need to be calculated.

[0145] In this embodiment, after the photon collides with the particle and scatters, the scattering angle is determined by the Henyey-Greenstein phase function, and the sampling of the scattering angle θ0is represented as:

[0146]

[0147] In the formula, is a random number in the range of [0, 1] generated by the linear congruential method, and g is an asymmetry factor that can be calculated by the Mie scattering theory. After determining the scattering direction of the photon, the motion trajectory of the photon is further tracked, and the random free step length l between the adjacent two scattering of the photon can be represented as:

[0148]

[0149] In the formula, ε l is a random number in the range of [0, 1] generated by the linear congruential method, and the turbidity τ can be determined by the extinction coefficient and the particle coefficient concentration.

[0150] As shown in Figure 8 , it is assumed that the light beam propagates along the x-axis direction, and the parallel light is incident. Taking the center point of the emitter as the origin, the initial emission coordinates (x0, y0) of the photon are:

[0151]

[0152] In the formula, ε3 is a random number in the range of [0, 1] generated by the linear congruential method, and at this time, the scattering direction of the photon is θ1=θ0, and the incident light is parallel light, so θ0=0. Combined with the coordinates of the photon entering the sample cell and the random free step length between adjacent scattering, the coordinates (x1, y1) of the first scattering of the photon can be represented as:

[0153]

[0154] The transmission process of the photon in the particle medium is obtained by judging the collision type, calculating the scattering angle and the scattering random free step length, if the photon is absorbed, the transmission process is terminated, otherwise, the process continues. The scattering direction of the photon at the nth scattering is θ n = θ n-1+θ0, the position of the particle in the nth collision can be represented as:

[0155]

[0156] The theoretical extinction spectrum can be calculated by counting the number N of photons that ultimately reach the receiver.

[0157] E = ln(I / I0) = ln(N / N) set ).

[0158] In the formula, N is the total number of received and transmitted photons. set To determine the photon count, the photon sample size is typically between 100,000 and 1 million. (Combined with...) Figure 9 As shown, a transmission of 100,000 photons was used to simulate the photon trajectory of a polystyrene particle with R = 0.2 μm. It can be seen that, for a given particle size, the number of transmitted photons gradually increases with increasing wavelength. According to light scattering theory, as the wavelength increases, the dimensionless parameter α (α = 2πR / λ) of the submicron particles decreases. Combined with the formula for calculating the random free step length, the probability of collimated photon transmission increases. Since the receiver is relatively far from the sample cell, the probability of collimated photon transmission increases. Because the receiver is far from the sample cell, the probability of the received photons being scattered is very small, decreasing with increasing wavelength, and is mainly single scattering. The number of escaped photons gradually decreases with increasing wavelength, with forward escape being the most common. Combined with… Figure 10 As shown, when the particle sizes of the two particles are different, R1 = 0.2 μm and R2 = 0.15 μm, the extinction spectrum distribution of the mixtures with different mixing ratios φ shows that as the wavelength of the incident light increases, the extinction spectrum of the different mixing ratios decreases. The extinction spectrum decreases differently due to the influence of the extinction coefficient of the high-density glass, indicating that the increase of the proportion of high-density glass has a greater impact on the extinction spectrum trend.

[0159] The objective function for constructing the experimentally despectrated spectrum is obtained based on the calculated theoretical despectrated spectrum.

[0160]

[0161] Where, λ i Given the wavelength, R1, R2, and φ are parameters to be determined, and E... m The experimental eliminated spectrum is represented by E, and the theoretical eliminated spectrum is represented by E. The particle size and mixing ratio are obtained by optimizing the objective function J. The optimization process can be implemented using the Particle Swarm Optimization (PSO) algorithm, while other optimal algorithms are not excluded.

[0162] The particle size and mixing ratio measurement method described above, in extinction measurement, the incident light is scattered and absorbed by the particle medium, and the transmitted light intensity is attenuated. The process is described by establishing a theoretical model and calculating the theoretical extinction spectrum. The extinction spectrum is measured by a spectrometer. Then, by comparing the theoretical model calculation and the experimental extinction spectrum, the particle size and mixing ratio of the mixed particle system are obtained by minimizing the error of the two. The theoretical model currently used for extinction spectrum particle size and concentration measurement only considers the light energy attenuation mechanism in a two-phase medium containing only one type of particle. However, due to the difference in particle types and particle properties, the light energy attenuation under the action of light wavelength is caused, which leads to the inapplicability of the single theoretical model used in the past and may cause errors in particle size measurement. The method describes the light energy fluctuation in the medium of two mixed particles by the Monte Carlo method, and calculates the extinction spectrum under this condition, thereby obtaining a particle size and mixing ratio measurement method for two mixed particles. It has good practicability in laboratory scientific research and online measurement and industrial site.

[0163] The particle size and mixing ratio measurement device provided by the present application is described below. The particle size and mixing ratio measurement device described below can be referred to in conjunction with the particle size and mixing ratio measurement method described above.

[0164] As shown in Figure 11 In one embodiment, a particle size and mixing ratio measurement device includes a measurement module 1110, a first acquisition module 1120, a judgment module 1130, a second acquisition module 1140, a third acquisition module 1150, and a function construction module 1160.

[0165] The measurement module 1110 is configured to obtain a corresponding experimental extinction spectrum by performing extinction method measurement on a two-phase system mixed with first solid particles and second solid particles, the first solid particles and the second solid particles being two different types of solid particles.

[0166] The first acquisition module 1120 is configured to obtain the extinction coefficient of the first solid particles and the second solid particles under the action of light by calculation.

[0167] The judgment module 1130 is configured to obtain the albedo of the first solid particles and the second solid particles by calculation, and to judge whether the corresponding photon is scattered. If the corresponding photon is scattered, the

[0168] The second acquisition module 1140 is configured to obtain the scattering angle when the photon is scattered and the random free step length between adjacent two scattering of the photon.

[0169] The third obtaining module 1150 is configured to determine the emission direction of the emitted photons based on the scattering angle when the photons are scattered, and to obtain a theoretical extinction spectrum of the two-phase system mixed with the first solid particles and the second solid particles by calculation.

[0170] The function construction module 1160 is configured to obtain a target function based on the experimental extinction spectrum and the theoretical extinction spectrum, and to solve the particle size and the mixing number ratio of the first solid particles and the second solid particles by using the target function.

[0171] In this embodiment, the particle size and mixing ratio measuring device provided by the application is provided with the measuring module, which is specifically configured to:

[0172] When the measuring area does not contain solid particles, the laser from the laser emitter is received by the receiver in the measuring area, and a first receiving signal is obtained.

[0173] When the measuring area contains solid particles, the laser from the laser emitter is received by the receiver in the measuring area, and a second receiving signal is obtained.

[0174] The signal intensity spectrum of a plurality of wavelengths of the laser is obtained based on the first receiving signal and the second receiving signal, so as to obtain an experimental extinction spectrum corresponding to different wavelengths.

[0175] The first receiving signal is the laser signal corresponding to the measuring area without solid particles, and the second receiving signal is the laser signal corresponding to the measuring area containing solid particles.

[0176] In this embodiment, the particle size and mixing ratio measuring device provided by the application further comprises a simulation module, which is configured to:

[0177] The light scattering process is simulated by using the Monte Carlo method, and the incident light in the scattering process is discretized into a plurality of discontinuous photons to establish a probability model.

[0178] The movement direction of the photons is obtained based on the interaction between the photons and the particles, and the movement direction is used to describe the absorption and scattering processes of the photons after interacting with the solid particles.

[0179] In this embodiment, the particle size and mixing ratio measuring device provided by the application is provided with the first obtaining module, which is specifically configured to:

[0180] When the photons collide with the solid particles, the type of the solid particles is determined by using the random number generated by the linear congruential method.

[0181] When the solid particles have the absorption and scattering processes, the extinction coefficient is obtained by calculation.

[0182] In this embodiment, the particle size and mixing ratio measuring device provided by the application is provided with the judging module, which is specifically configured to:

[0183] Based on the extinction coefficient, the corresponding scattering cross section and the extinction cross section are obtained, and the albedo is the ratio of the scattering cross section and the extinction cross section.

[0184] If the random number is greater than the albedo, the photon is absorbed, and if the random number is less than or equal to the albedo, the photon is scattered.

[0185] In this embodiment, the particle size and mixing ratio measuring device provided by the application is provided, and the second acquisition module is specifically used for:

[0186] After the photon collides with the solid particles to scatter, the scattering angle is determined by the Henyey-Greenstein phase function.

[0187] Based on the scattering angle and the scattering direction of the scattered photon, the motion trajectory of the photon is obtained, and the random free step is obtained by calculation.

[0188] In this embodiment, the particle size and mixing ratio measuring device provided by the application is provided, and the third acquisition module is specifically used for:

[0189] Based on the coordinates of the photon in the measurement region and the random free step between adjacent scattering, the coordinates of the first scattering of the photon are obtained.

[0190] According to the collision type of the photon and the solid particles, the scattering angle and the random free step, the transmission process of the photon in the solid particles is judged, if the photon is absorbed, the transmission process is stopped, if the photon is scattered, the transmission process is continued.

[0191] The number of photons reaching the receiver is obtained by statistics, and the theoretical extinction spectrum is obtained based on the number of photons.

[0192] Figure 12 An example of an electronic device is shown in the physical structure diagram, which can be a smart terminal, and its internal structure diagram can be as shown in Figure 12 The electronic device includes a processor, a memory and a network interface connected by a system bus. The processor of the electronic device is used to provide computing and control capability. The memory of the electronic device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operating system and the computer program in the non-volatile storage medium to run. The network interface of the electronic device is used to communicate with external terminals through network connection. The computer program is executed by the processor to implement the particle size and mixing ratio measuring method, which includes:

[0193] The corresponding experimental extinction spectrum is obtained by measuring the extinction method on the two-phase system mixed with the first solid particles and the second solid particles, and the first solid particles and the second solid particles are two different types of solid particles.

[0194] obtaining extinction coefficients of the first solid particles and the second solid particles under the action of light waves by calculation;

[0195] obtaining albedos of the first solid particles and the second solid particles by calculation, and judging whether the corresponding photons are scattered; if the corresponding photons are scattered, then

[0196] obtaining a scattering angle when the photons are scattered and a random free step length between adjacent two scattering of the photons;

[0197] determining an emission direction of the emitted photons based on the scattering angle when the photons are scattered, and obtaining a theoretical extinction spectrum corresponding to the two-phase system mixed with the first solid particles and the second solid particles by calculation;

[0198] obtaining a target function based on the experimental extinction spectrum and the theoretical extinction spectrum, the target function being used to solve particle sizes and a mixing number ratio of the first solid particles and the second solid particles.

[0199] Those skilled in the art can understand that, Figure 12 The structure shown in the figure is only a block diagram of part of the structure related to the scheme of the present application, and does not constitute a limitation on the electronic device to which the scheme of the present application is applied. The specific electronic device can include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0200] In another aspect, the present application also provides a computer storage medium storing a computer program, the computer program being executed by a processor to implement a particle size and mixing ratio measurement method, the method comprising:

[0201] obtaining an experimental extinction spectrum corresponding to the two-phase system mixed with the first solid particles and the second solid particles by extinction method measurement, the first solid particles and the second solid particles being two different types of solid particles;

[0202] obtaining extinction coefficients of the first solid particles and the second solid particles under the action of light waves by calculation;

[0203] obtaining albedos of the first solid particles and the second solid particles by calculation, and judging whether the corresponding photons are scattered; if the corresponding photons are scattered, then

[0204] obtaining a scattering angle when the photons are scattered and a random free step length between adjacent two scattering of the photons;

[0205] determining an emission direction of the emitted photons based on the scattering angle when the photons are scattered, and obtaining a theoretical extinction spectrum corresponding to the two-phase system mixed with the first solid particles and the second solid particles by calculation;

[0206] The objective function is used to solve the particle size and the mixing number ratio of the first solid particles and the second solid particles.

[0207] In another aspect, a computer program product or computer program is provided, the computer program product or computer program comprising computer instructions stored in a computer-readable storage medium. A processor of an electronic device reads the computer instructions from the computer-readable storage medium, and the processor implements a particle size and mixing ratio measurement method when executing the computer instructions, the method comprising:

[0208] An experimental extinction spectrum is obtained by performing an extinction method measurement on a two-phase system mixed with first solid particles and second solid particles, the first solid particles and the second solid particles being two different types of solid particles;

[0209] The extinction coefficients of the first solid particles and the second solid particles under the action of light waves are obtained by calculation;

[0210] The albedos of the first solid particles and the second solid particles are obtained by calculation, and it is determined whether a corresponding photon is scattered; if the corresponding photon is scattered, then

[0211] The scattering angle when the photon is scattered and the random free step length between two adjacent scattering of the photon are obtained;

[0212] The scattering angle when the photon is scattered is determined to determine the emission direction of the emitted photon, and a theoretical extinction spectrum corresponding to the two-phase system mixed with the first solid particles and the second solid particles is obtained by calculation;

[0213] An objective function is obtained based on the experimental extinction spectrum and the theoretical extinction spectrum, and the objective function is used to solve the particle size and the mixing number ratio of the first solid particles and the second solid particles.

[0214] A person of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiments can be completed by a computer program instructing related hardware, and the computer program can be stored in a non-volatile computer readable storage medium. When the computer program is executed, it can include the processes of the above-mentioned embodiments. Any reference to memory, storage, database or other medium used in the embodiments provided by the present application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory can include random access memory (RAM) or external cache memory.

[0215] By way of illustration and not limitation, RAM is available in many forms such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), Synchlink DRAM (SLDRAM), Rambus direct RAM (RDRAM), direct Rambus dynamic RAM (DRDRAM), and Rambus dynamic RAM (RDRAM) etc.

[0216] The technical features of the above embodiments can be combined in any manner. In order to make the description simple, all possible combinations of the technical features in the above embodiments are not described, however, as long as the combinations of the technical features do not exist in contradiction, they should be considered as the scope of the present disclosure.

[0217] The above embodiments only express several implementation manners of the present application, the description is more specific and detailed, but it should not be understood as the limitation of the patent scope of the present application. It should be pointed out that for ordinary skilled in the art, several modifications and improvements can be made without departing from the concept of the present application, which belongs to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A method for measuring particle size and mixing ratio, characterized in that, The method comprises: obtaining a corresponding experimental extinction spectrum by performing an extinction method measurement on a two-phase system mixed with first solid particles and second solid particles, the first solid particles and the second solid particles being two different types of solid particles; obtaining extinction coefficients of the first solid particles and the second solid particles under the action of light waves by calculation; obtaining albedos of the first solid particles and the second solid particles by calculation, and determining whether a corresponding photon is scattered; if the corresponding photon is scattered, then obtaining a scattering angle when the photon is scattered and a random free step length between two adjacent scattering processes of the photon; determining an exit direction of the photon based on the scattering angle when the photon is scattered, and obtaining a corresponding theoretical extinction spectrum of the two-phase system mixed with the first solid particles and the second solid particles by calculation; obtaining an objective function based on the experimental extinction spectrum and the theoretical extinction spectrum, the objective function being used to solve particle sizes and a mixing number ratio of the first solid particles and the second solid particles.

2. The particle size and mixing ratio measurement method according to claim 1, characterized by, The method comprises: when the measurement region does not contain the solid particles, receiving laser from a laser emitter by a receiver in the measurement region, and obtaining a first receiving signal; when the measurement region contains the solid particles, receiving laser from the laser emitter by the receiver in the measurement region, and obtaining a second receiving signal; obtaining signal intensity spectra of multiple wavelengths of the laser based on the first receiving signal and the second receiving signal, so as to obtain experimental extinction spectra corresponding to different wavelengths; wherein the first receiving signal is a laser signal corresponding to the measurement region not containing the solid particles, and the second receiving signal is a laser signal corresponding to the measurement region containing the solid particles.

3. The particle size and mixing ratio measurement method according to claim 2, characterized by, The method comprises: using a Monte Carlo method to simulate light scattering processes, and discretizing incident light in the scattering processes into multiple discontinuous photons to establish a probability model; obtaining a motion direction of the photon based on interaction between the photon and the particle, the motion direction being used to describe absorption and scattering processes of the photon after interaction with the solid particle.

4. The particle size and mixing ratio measurement method according to claim 3, characterized by, The method comprises: when the photon collides with the solid particle, determining a type of the solid particle by a random number generated by a linear congruential method; when the solid particle has the absorption and scattering processes, obtaining the extinction coefficient by calculation.

5. The particle size and mixing ratio measurement method according to claim 4, characterized by, The method comprises: based on the extinction coefficient, obtaining albedos of a scattering cross section and an extinction cross section, the albedo being a ratio of the scattering cross section to the extinction cross section; if the random number is greater than the albedo, the photon is absorbed, and if the random number is less than or equal to the albedo, the photon is scattered.

6. The particle size and mixing ratio measurement method according to claim 5, characterized by, The scattering angle when the photon is scattered and the random free step length between two adjacent scattering of the photon are obtained, including: The scattering angle is determined by a Henyey-Greenstein phase function after the photon is scattered by colliding with the solid particle; The movement track of the photon is obtained based on the scattering angle and the scattering direction after the photon is scattered, and the random free step length is obtained by calculation.

7. The particle size and mixing ratio measurement method according to claim 5, characterized by, The emission direction of the photon is determined based on the scattering angle when the photon is scattered, and the theoretical extinction spectrum of the two-phase system mixed with the first solid particle and the second solid particle is obtained by calculation, including: The coordinate of the photon when the photon is scattered for the first time is obtained based on the coordinate of the photon in the measurement area and the random free step length between two adjacent scattering; The transmission process of the photon in the solid particle is determined according to the collision type of the photon and the solid particle, the scattering angle and the random free step length, if the photon is absorbed, the transmission process is stopped, if the photon is scattered, the transmission process is continued; The number of photons reaching the receiver is obtained by statistics, and the theoretical extinction spectrum is obtained based on the number of photons.

8. A particle size and mixing ratio measuring device characterized by comprising: The device includes: The measurement module is configured to obtain an experimental extinction spectrum of a two-phase system mixed with a first solid particle and a second solid particle by extinction method measurement, the first solid particle and the second solid particle being two different types of solid particles; The first obtaining module is configured to obtain extinction coefficients of the first solid particle and the second solid particle under the action of light waves by calculation; The judgment module is configured to obtain albedos of the first solid particle and the second solid particle by calculation, and determine whether a corresponding photon is scattered; if the corresponding photon is scattered, The second obtaining module is configured to obtain a scattering angle when a photon is scattered and a random free step length between two adjacent scattering of the photon; The third obtaining module is configured to determine an emission direction of an emitted photon based on the scattering angle when the photon is scattered, and obtain a theoretical extinction spectrum of the two-phase system mixed with the first solid particle and the second solid particle by calculation; The function construction module is configured to obtain a target function based on the experimental extinction spectrum and the theoretical extinction spectrum, the target function being used to solve particle sizes and a mixing number ratio of the first solid particle and the second solid particle.

9. An electronic device comprising a memory and a processor, the memory storing a computer program, characterized in that, The processor executes the computer program to realize the steps of the method in any one of claims 1 to 7.

10. A computer storage medium storing a computer program, characterized in that, The computer program is executed by the processor to realize the steps of the method in any one of claims 1 to 7.

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