Gas-solid two-phase flow parameter measurement method, electronic equipment and storage medium

Abstract

The present invention discloses a method for measuring flow parameters of a gas-solid two-phase flow, an electronic device and a storage medium, wherein the method for measuring flow parameters of a gas-solid two-phase flow includes: obtaining a capacitance vector of a region to be measured, and reconstructing a real dielectric constant distribution of the region to be measured; based on the reconstructed real dielectric constant distribution, under the assumption of particle moisture, obtaining a particle concentration distribution and particle moisture; based on the particle concentration distribution and particle moisture, obtaining a complex dielectric constant distribution of a microwave frequency band measurement region; calculating the attenuation of microwaves under the complex dielectric constant distribution; setting a comparison value, and according to the comparison between the calculated microwave attenuation under the complex dielectric constant distribution and the actual measured microwave attenuation, correcting the assumed particle moisture to meet the comparison value; and taking the particle moisture that meets the comparison value as the final particle moisture. The measurement method of the present invention that combines capacitance tomography with the microwave method improves the measurement accuracy and measurement range.

Description

Technical Field

[0001] The invention relates to the technical field of gas-solid two-phase flow measurement, in particular to a method for measuring flow parameters of gas-solid two-phase flow. Background Art

[0002] Gas-solid two-phase flow is mainly a mixture of gas and solid phases, and is one of the common multiphase flow systems. Gas-solid two-phase flow is widely present in various industrial production and machinery manufacturing. For example, the processes of drug production in the pharmaceutical industry, such as crushing, mixing, drying, granulation, coating and tableting, are all carried out in a fluidized bed, which is the flow process of gas-solid two-phase flow. At the same time, gas-solid two-phase flow is also widely used in the energy and chemical industries. For example, the gasification of coal in the gas industry is also a typical gas-solid two-phase flow application. With the widespread application of gas-solid two-phase flow, the demand for measuring the flow parameters of gas-solid two-phase flow has emerged. The concentration parameter is one of the most important flow parameters of gas-solid two-phase flow. On the one hand, the concentration contains important flow laws, which is extremely critical to the study of the flow mechanism of gas-solid two-phase flow; on the other hand, the concentration parameter can reflect the condition of the material in the production process, which is of great significance for monitoring the production process, mastering the manufacturing process, and improving production efficiency. Therefore, with the continuous deepening of research on gas-solid two-phase flow and the rapid growth of measurement needs in engineering practice, exploring accurate, real-time, non-contact online measurement methods and technologies for gas-solid two-phase flow particle concentration parameters has become one of the most important research topics.

[0003] For the measurement of gas-solid two-phase flow concentration parameters, in addition to considering the particle phase concentration distribution, the impact of changes in particle properties should also be considered. In the production process, the change in particle properties is mainly manifested as a change in particle moisture content, which is closely related to the operating conditions of the process system. For example, in the dense phase transportation of coal powder in coal gasification, the moisture content of coal powder needs to be controlled within an appropriate range to improve the operational flexibility of the coal powder system, while saving energy and reducing consumption and increasing benefits. In addition, the moisture content of some powder particles also changes dynamically during humidification and drying. The change in moisture will change the viscosity and adhesion of the particles, seriously affecting the gas-solid flow characteristics. On the other hand, the existing measurement methods are generally based on "dry" materials, that is, the particle properties remain unchanged, ignoring the impact of changes in particle moisture, resulting in low measurement accuracy of existing instruments and limited applicable measurement environments. Therefore, studying the changes in particle properties, especially the gas-solid two-phase flow concentration distribution measurement methods and technologies during the dynamic changes in particle moisture, has important theoretical significance and application value.

[0004] Both electrical capacitance tomography (ECT) and microwave method can be used to measure the concentration parameters of gas-solid two-phase flow, and both are affected by the moisture content of particles. They have unique advantages such as non-contact, wide bandwidth, anti-interference, simple structure, easy operation and low cost, and have great application prospects in the measurement of gas-solid two-phase flow parameters.

[0005] Capacitance tomography (ECT) is a measurement method formed by combining capacitance method with tomography method. The basic principle of capacitance method is that different substances will show different dielectric constants, and the equivalent dielectric constants of the same substance at different concentrations are also different, so different capacitance values ​​will be obtained when using capacitance sensors for measurement. Based on this principle, the concentration parameters of gas-solid two-phase flow can be measured. The principle of process tomography is to use a certain excitation source to obtain projection data outside the object to be measured, and then reconstruct the internal characteristics of the object to be measured through a certain mathematical reconstruction method. Therefore, capacitance tomography technology (ECT) constructs the relationship between the dielectric constant distribution and the capacitance vector through the combination of the above two methods, and reconstructs the dielectric constant distribution according to the measured capacitance value. When the moisture content of the measured object is determined, the medium distribution can be reconstructed according to the distribution of the dielectric constant; and when the concentration distribution of the measured object is determined, the moisture content of the measured object can be inversely calculated. However, if the moisture content and concentration of the measured object change dynamically, the concentration distribution of the measured object cannot be reconstructed. Therefore, capacitance tomography has great limitations in the face of measurement objects with changing particle properties (moisture content), and it is necessary to integrate measurement with other measurement methods to solve this problem.

[0006] The principle of the microwave method is that when microwaves pass through particles, scattering and absorption will occur. The imaginary part of the dielectric constant of water in a specific microwave frequency band is very large, and the ability to lose electric field energy is very strong. Therefore, when microwaves pass through, they are severely attenuated, which is manifested as high sensitivity to moisture. Therefore, when the particle concentration is determined or the measurement object is a static object, microwaves are often used to measure moisture; and when the particle moisture is known, the particle concentration information can be obtained through the attenuation of microwaves.

[0007] Both electrical capacitance tomography and microwave technology can be used to measure concentration parameters of gas-solid two-phase. However, due to the limited information obtained from the single measurement mechanism, they can only be used to measure concentration parameters under limited conditions when used alone, and cannot solve the problem of measuring concentration parameters during the dynamic change of particle moisture. Changes in particle moisture will lead to large changes in the equivalent dielectric constant of the particles. When the moisture content of the conveyed material changes, the output error of the sensor is extremely large and cannot reflect the true situation of the particle flow. Multi-sensor fusion is an effective way to solve this problem and an important research direction. By integrating multiple sensors and making full use of the measurement characteristics of each sensor for information fusion, that is, combining microwave method with electrical capacitance tomography, accurate measurement of gas-solid two-phase particle flow process can be achieved.

[0008] Although the combined measurement technology of capacitance tomography and microwave has made some preliminary progress, the existing combined measurement technology generally uses multiple sensors to complement each other, rather than integrating multiple measurement technologies, and there is no mature measurement system for this technology. The existing ECT and microwave combined measurement technology uses capacitance tomography and microwave tomography technology for wet particle concentration distribution reconstruction. The capacitance tomography has a good imaging effect, but the capacitance is saturated at high moisture content and the imaging effect is poor. Microwave tomography can still be used at higher particle moisture content. Therefore, microwave imaging is used at high moisture content. Through the combination of the two, different measurement technologies are used for different moisture content. The particle flow characteristics within a large range of particle moisture changes can be studied, but the problem of moisture affecting particle concentration measurement is not solved. Although this multi-sensor integration aims to increase the measurement range, each sensor still works independently based on its own principles and characteristics, and the measurement accuracy of a single sensor is not improved. There is usually a problem of inconsistent sensitive space. Summary of the invention

[0009] Aiming at the problem of measuring the concentration parameters of gas-solid two-phase flow in the process of dynamic change of particle moisture by electrical capacitance tomography, the present invention proposes a measurement method integrating electrical capacitance tomography with microwave method, which improves the measurement accuracy and measurement range and has important theoretical significance and application value.

[0010] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0011] A method for measuring flow parameters of a gas-solid two-phase flow, comprising:

[0012] Obtain the capacitance vector of the area to be measured and reconstruct the real dielectric constant distribution of the area to be measured;

[0013] Based on the reconstructed real dielectric constant distribution, the particle concentration distribution and particle moisture are obtained under the assumption of particle moisture;

[0014] Based on the particle concentration distribution and particle moisture, the distribution of complex dielectric constant in the microwave frequency band measurement area is obtained;

[0015] According to the obtained distribution of complex dielectric constant in microwave frequency band, the attenuation of microwave under the distribution of complex dielectric constant is calculated;

[0016] A contrast value is set, and based on the comparison between the calculated microwave attenuation under the complex dielectric constant distribution and the actually measured microwave attenuation, the assumed particle moisture is corrected to meet the contrast value; the particle moisture that meets the contrast value is taken as the final particle moisture.

[0017] When ECT measures particle concentration distribution, moisture has a huge impact on measurement accuracy, and the impact of moisture cannot be distinguished. Therefore, the present invention uses ECT and microwave fusion measurement methods to simultaneously measure particle concentration distribution and particle moisture, thereby achieving the purpose of accurately measuring particle concentration distribution in working conditions with varying moisture content.

[0018] The method to correct the assumed particle moisture to meet the comparison value is:

[0019] Set the contrast value δ;

[0020] Compare the microwave attenuation calculated under the complex dielectric constant distribution with the microwave attenuation actually measured. If α N >α 0 Increase the water content W N , if α N <α 0 Then reduce the water content W N , the microwave attenuation under the complex dielectric constant distribution is repeatedly calculated until |α N -α 0 |<δ converges;

[0021] After convergence is met, the particle concentration distribution and moisture content are output.

[0022] The contrast value δ is 0.1% to 0.5%.

[0023] The present invention also provides an electronic device, comprising:

[0024] one or more processors;

[0025] A memory for storing one or more programs;

[0026] When the one or more programs are executed by the one or more processors, the one or more processors implement the gas-solid two-phase flow parameter measurement method.

[0027] The present invention also provides a storage medium on which a computer program is stored, characterized in that when the program is executed by a processor, the gas-solid two-phase flow parameter measurement method is implemented.

[0028] Compared with the prior art, the present invention has the following advantages:

[0029] 1) The capacitance tomography and microwave fusion measurement method of the present invention overcomes the problem of measuring the concentration distribution of the flow of particle moisture changes. The present invention decouples the influence of moisture through the microwave and ECT fusion measurement method, thereby obtaining a more accurate concentration measurement result.

[0030] 2) The integration of electrical capacitance tomography and microwave method realizes the joint use of sensors in mechanism, improves the richness of information acquisition, achieves the purpose of expanding the measurement range, and improves the measurement accuracy.

[0031] 3) In terms of hardware structure, based on the ECT sensor, the microwave transmission system adopts oblique emission to make the measurement area coincide with the ECT measurement area, solving the problem of inconsistent sensitive areas when the sensors are used together.

[0032] 4) In terms of software system, a dual-modal information acquisition method and a dual-modal information fusion method are proposed to closely integrate electrical capacitance tomography with microwave sensors, and to extract accurate moisture and concentration information from the information acquired by ECT and microwave through calculation and iteration. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 The information acquisition and fusion process of the measurement method of the present invention;

[0034] Figure 2 Flow chart of the measuring method of the present invention. DETAILED DESCRIPTION

[0035] The present invention is based on the measurement of flow parameters of variable moisture gas-solid two-phase flow, and uses ECT and microwave dual-modal information acquisition and fusion to achieve the measurement of particle concentration distribution of variable moisture gas-solid two-phase flow. The flow chart of capacitance tomography and microwave dual-modal information acquisition and fusion is as follows: Figure 1 shown.

[0036] First, the main structure of the sensor part includes an ECT capacitance sensor array, a microwave transmitting and transmitting receiving antenna. The ECT sensor array is composed of 8 electrodes, voltage can be applied between the electrodes, and the working mode of the electrodes is single excitation and multiple detection, that is, an excitation voltage is applied to one electrode in turn, and the remaining electrodes are grounded as detection electrodes, so that a total of 28 capacitance values ​​between different electrode pairs can be obtained. Usually the excitation frequency between electrodes is in the range of 0.1-10MHz, and the present invention uses an excitation frequency of 1MHz. In order to ensure that the measurement sensitive areas of the microwave system and the ECT system are consistent, the microwave transmission system adopts an oblique emission method, the transmitting antenna provides excitation, and the receiving antenna feedback attenuation, so as to achieve the purpose of obtaining flow information in the same sensitive area. Microwaves are usually electromagnetic waves with a frequency range of 300MHz to 300GHz, and the present invention uses 10GHz microwaves.

[0037] Based on the above sensor structure, the capacitance signal of the capacitance tomography system and the microwave attenuation signal of the microwave system are obtained simultaneously. The capacitance signal can be used to obtain the distribution of the dielectric constant in the pipeline through image reconstruction, while the microwave attenuation signal also reflects the particle concentration distribution and moisture content in the pipeline.

[0038] On this basis, the capacitance signal and microwave signal are iteratively solved to achieve information fusion and decoupling, and the concentration distribution and moisture content in the pipeline can be output.

[0039] The basic principle of iterative solution of capacitance signal and microwave signal is that the polarization property of the material in the electric field can be expressed by the complex dielectric constant ε:

[0040] ε=ε'-iε″

[0041] Where ε' is the real dielectric constant of the material, which characterizes the ability of the material to store electric field energy; ε" is the loss factor, which characterizes the ability of the material to lose electric field energy; and i is the imaginary unit.

[0042] Usually, flowing particles such as coal powder and drug powder are non-polar molecules, and the imaginary part of their dielectric constant does not need to be considered, and the real part of the dielectric constant changes very little; however, water molecules are polar molecules, and the real and imaginary parts of their complex dielectric constants change significantly with frequency. Based on the above phenomenon, the particle concentration distribution and moisture information can be decoupled by obtaining different signals in the capacitance tomography frequency band and the microwave frequency band.

[0043] The information fusion iterative process is as follows: Figure 2 As shown, the following steps need to be implemented:

[0044] (1) Using the capacitance tomography system, the measured capacitance vector is obtained and the actual dielectric constant distribution ε0 of the measured area is reconstructed. * .

[0045] The reconstruction process is mainly to solve the inverse problem of ECT. The direct problem corresponding to the inverse problem in ECT is that different dielectric distributions have different dielectric constants. When the dielectric distribution changes, it will cause the dielectric constant of the measured area to change, thereby causing the capacitance value measured by the sensor to change. Therefore, the inverse problem is to establish the relationship between the capacitance value and the dielectric constant distribution, reconstruct the dielectric constant distribution from the capacitance value, and then reconstruct the dielectric distribution according to the equivalent medium theory.

[0046] For the reconstruction of capacitance value to dielectric constant distribution, the mapping relationship between dielectric distribution and capacitance vector is usually abstracted into a simple linear relationship, and this relationship is called "sensitive field". The relationship between dielectric distribution and capacitance expressed by sensitive field is:

[0047] λ=S·g

[0048] In the formula, λ is the normalized capacitance vector, S is the sensitive field matrix, and g is the normalized dielectric constant or image grayscale. Therefore, in theory, multiply S on both sides of the above formula by -1The dielectric constant of the area to be measured can be obtained. However, in practice, S does not have an inverse matrix, so the transposed matrix S of S is used. T Instead, we get an approximate estimate of the image grayscale:

[0049]

[0050] This is the linear back projection algorithm (LBP) in electrical capacitance tomography technology. The LBP algorithm is simple to calculate, fast and has good real-time performance, but the error is large and the image reconstruction is seriously distorted. Therefore, a variety of algorithms have been developed to improve the reconstruction accuracy.

[0051] Common reconstruction algorithms include linear back projection algorithm (LBP), single value decomposition (SVD), Tikhonov regularization method, Newton-Raphson method, iterative Tikhonov method, steepest descent method, Landweber iteration method, ART algorithm, model-based algorithm, neural network method, etc.

[0052] The normalized dielectric constant obtained through the above reconstruction process is The real dielectric constant distribution ε'0 can be restored through the inverse process of normalization.

[0053] (2) Based on the reconstructed real dielectric constant distribution ε'0, under the assumption of water content, the particle concentration distribution β is obtained N and particle moisture W N .

[0054] This process mainly requires the use of the equivalent dielectric constant formula:

[0055]

[0056] Where V is the total volume of the calculation area, V A is the volume of air in the mixture, m D and m w are the mass of dry material and water, respectively, D and ρ w are the material density and water density, ε'0 is the reconstructed real dielectric constant distribution, ε' D-C and ε' w-C are the real dielectric constants of dry material and water in the electrical capacitance tomography frequency band, respectively.

[0057] When the moisture content is determined, i.e., m w When determined, due to V A It can be expressed as:

[0058]

[0059] Therefore, combined with ε'0, the particle concentration distribution β can be solvedN and particle moisture W N .

[0060] The calculation formula for this process is as follows:

[0061]

[0062] in, is the volume concentration of particles in the measurement area β N .

[0063] (3) Based on particle concentration distribution β N and particle moisture W N , and continue to use the equivalent dielectric constant formula to obtain the distribution of the complex dielectric constant in the microwave frequency band measurement area. Substitute the particle dielectric constant and the complex dielectric constant of water in the microwave frequency band, and solve the real part of the dielectric constant of the mixture in this frequency band:

[0064]

[0065] In the formula, ε' M is the real part of the effective dielectric constant of the mixture in the microwave frequency band, ε' D-M and ε' w-M are the real parts of the dielectric constants of dry materials and water in the microwave frequency band respectively.

[0066] The imaginary part of the dielectric constant is:

[0067]

[0068] In the formula, ε” M is the imaginary part of the effective dielectric constant of the mixture at microwave frequencies, ε” D-M and ε” w-M are the imaginary parts of the dielectric constants of dry materials and water in the microwave frequency band respectively.

[0069] (4) When the distribution of complex dielectric constant in the microwave frequency band is calculated in (3), the attenuation of microwaves in this case can be calculated based on Maxwell's differential equations.

[0070] Maxwell's differential equations are shown below:

[0071]

[0072] In the formula, For divergence calculation, For curl calculation, D is electric flux density, E is electric field intensity, B is magnetic flux density, H is magnetic field intensity, ρ is charge density, and j is current density. When calculating attenuation, the finite element method is used based on the Maxwell differential equations to calculate the attenuation of microwaves when the particle concentration distribution and moisture content are known.N .

[0073] The main steps of conventional finite element calculations include regional discretization, interpolation function selection, equation system establishment, and equation system solution. The regional discretization in the calculation process of this patent is mainly to establish an opposing three-dimensional system model in the finite element calculation software according to the actual measurement system, and use tetrahedrons as basic discrete units. Smaller tetrahedron units are used for denser division in the parts close to the microwave antenna and the insulating pipe.

[0074] The selection of the interpolation function needs to be based on the tetrahedral discrete unit used above. The present invention chooses to use the linear interpolation method:

[0075]

[0076] In the formula, is the electric potential at the point (x, y) in the e-th unit, is the interpolation coefficient to be determined within the e-th unit.

[0077] In terms of establishing and solving the system of equations, from a broad perspective, the governing equations of the three-dimensional electromagnetic field problem should be the three-dimensional Maxwell equations, but in general, for the convenience of solving and modeling, the vector Helmholtz equations satisfied by the electric field intensity derived from the two curl equations of the Maxwell equations are usually selected as the governing equations. For example, in the finite element calculation software used in the present invention, the governing equation used is:

[0078]

[0079] Where E is the electric field intensity vector corresponding to the time-harmonic field, k0 is the free space wave number, μ r is the complex relative permeability, ε r is the complex relative permittivity.

[0080] According to the control equation and the characteristics that the electric potential on the common edges and common points of each tetrahedral unit is the same, the electric potential distribution of the entire field can be derived, and the multivariate algebraic equation system is obtained:

[0081] AΦ (i) =B

[0082] In the formula, A is the symmetric matrix of the number of tetrahedrons divided; Φ (i) and B are both tetrahedron dimension column vectors, Φ (i) is the matrix composed of the potentials of each node to be solved, and B is the boundary condition, which can be the first-class Dirichlet condition and the second-class Neumann condition. According to this formula, the potential matrix Φ can be solved (i)Solve it, and then according to this potential matrix, we can get the potential of the microwave receiving antenna, and thus get the microwave attenuation.

[0083] (5) Microwave signal attenuation α N Compared with the actual measured microwave attenuation α 0 Compare and correct moisture W N , α N >α 0 Increase the water content W N , α N <α 0 Then reduce the water content W N , and repeat steps (2)-(5) until the microwave signal decays |α N -α 0 |<δ convergence, where δ is a smaller value, and it is recommended to be between 0.1% and 0.5%. After the convergence is satisfied, the particle concentration distribution and moisture content are output, thereby achieving accurate simultaneous measurement of particle concentration distribution and moisture.

[0084] According to the above specific implementation steps, for two typical manifolds of stratified flow and annular flow, capacitance tomography uses Landweber's iterative reconstruction algorithm, and the measurement object is particles with a relative dielectric constant of 9.75, and the particle concentration is 50%. The measurement and calculation are performed under three conditions of 5%, 10% and 15% water content, and the measurement accuracy is expressed by the phase content error. The results of the measurement and calculation are shown in Table 1. Obviously, when using the ECT and microwave fusion measurement method for calculation, the phase content error is significantly improved compared with the measurement and calculation method using only ECT, indicating that the present invention provides more accurate concentration distribution data.

[0085] Table 1 Comparison of measurement results of different flow types

[0086]

[0087] In order to accurately measure the gas-solid two-phase flow parameters during the dynamic change of particle water content, the present invention further studies the acquisition and fusion of capacitance and microwave dual-mode information based on the hardware research of capacitance and microwave dual-mode sensors. A dual-mode information acquisition method and a dual-mode information fusion method are proposed to achieve the measurement of the concentration distribution of water-containing particles.

Claims

1. A method for measuring flow parameters of a gas-solid two-phase flow, characterized in that: include: Obtain the capacitance vector of the area to be measured and reconstruct the real dielectric constant distribution of the area to be measured; Based on the reconstructed real dielectric constant distribution, the particle concentration distribution and particle moisture are obtained under the assumption of particle moisture; Based on the particle concentration distribution and particle moisture, the distribution of complex dielectric constant in the microwave frequency band measurement area is obtained; According to the obtained distribution of complex dielectric constant in microwave frequency band, the attenuation of microwave under the distribution of complex dielectric constant is calculated; A comparison value is set, and based on the comparison between the microwave attenuation calculated under the complex dielectric constant distribution and the microwave attenuation actually measured, the assumed particle moisture is corrected to meet the comparison value; the particle moisture meeting the comparison value is taken as the final particle moisture; Based on the reconstructed real dielectric constant distribution, under the assumption of particle moisture, the process of obtaining the particle concentration distribution and particle moisture uses the equivalent dielectric constant formula: Where ε'0 is the reconstructed real dielectric constant distribution, V is the total volume of the calculation area, and V A is the volume of air in the mixture, m D and m w are the mass of dry material and water, respectively, D and ρ w are the density of the material and the density of water respectively; ε' D-C and ε' w-c are the real dielectric constants of dry material and water in the electrical capacitance tomography frequency band, respectively; When the moisture content is determined, m w When determined, due to V A It is expressed as: Therefore, combined with ε'0, the particle concentration distribution β N and particle moisture W N ; The calculation formula for this process is as follows: in, is the volume concentration of particles in the measurement area β N ; Based on the particle concentration distribution β N and particle moisture W N , continue to use the equivalent dielectric constant formula to obtain the distribution of complex dielectric constant in the microwave frequency band measurement area; substitute the particle dielectric constant and the complex dielectric constant of water in the microwave frequency band, and solve the real part of the dielectric constant of the mixture in this frequency band: In the formula, ε' M is the real part of the effective dielectric constant of the mixture in the microwave frequency band, ε' D-M and ε' w-M are the real parts of the dielectric constants of dry materials and water in the microwave frequency band respectively; The imaginary part of the dielectric constant is: In the formula, ε” M is the imaginary part of the effective dielectric constant of the mixture at microwave frequencies, ε” D-M and ε” w-M are the imaginary parts of the dielectric constants of dry materials and water in the microwave frequency band, respectively; When the distribution of complex dielectric constant in microwave frequency band is calculated, the attenuation of microwave in this case is calculated based on Maxwell differential equations; Maxwell's differential equations are shown below: In the formula, For divergence calculation, For curl calculation, D is electric flux density, E is electric field intensity, B is magnetic flux density, H is magnetic field intensity, ρ is charge density, and j is current density; when calculating attenuation, the finite element method is used on the basis of Maxwell differential equations to calculate the attenuation of microwaves when the particle concentration distribution and moisture content are known. N ; Finite element calculation includes four parts: regional discretization, interpolation function selection, equation system establishment and equation system solution. Regional discretization uses tetrahedron as the basic discrete unit, and smaller tetrahedron units are used for denser division in the parts close to microwave antennas and insulating pipes. The selection of interpolation function needs to be based on the tetrahedral discrete unit used above, using the linear interpolation method: In the formula, is the electric potential at the point (x, y) in the e-th unit, is the interpolation coefficient to be determined in the e-th unit; In the finite element calculation, the governing equation used is: Where E is the electric field intensity vector corresponding to the time-harmonic field, k0 is the free space wave number, μ r is the complex relative permeability, ε r is the complex relative permittivity; According to the control equation and the characteristics that the electric potentials on the common edges and common points of each tetrahedral unit are the same, the electric potential distribution of the entire field is derived, and the multivariate algebraic equations are obtained: AF (i) =B In the formula, A is the symmetric matrix of the number and dimension of the divided tetrahedrons; Φ (i) and B are both tetrahedron dimension column vectors, Φ (i) is the matrix composed of the potentials of each node to be determined, and B is the boundary condition; According to the root multivariate algebraic equations, the potential matrix Φ is obtained by solving (i) ; Then according to the potential matrix Φ (i) , the electric potential of the microwave receiving antenna is obtained, thereby obtaining the microwave attenuation situation.

2. The method for measuring flow parameters of gas-solid two-phase flow according to claim 1, characterized in that: Based on the particle concentration distribution and particle moisture, the complex dielectric constant distribution of the microwave frequency measurement area is obtained, including: Calculate the real part of the dielectric constant of the mixture: In the formula, ε' M is the real part of the effective dielectric constant of the mixture in the microwave frequency band, ε' D-M and ε' w-M are the real parts of the dielectric constants of dry materials and water in the microwave frequency band respectively; Calculate the imaginary part of the dielectric constant of the mixture: In the formula, ε” M is the imaginary part of the effective dielectric constant of the mixture at microwave frequencies, ε” D-M and ε” w-M are the imaginary parts of the dielectric constants of dry materials and water in the microwave frequency band, respectively; The distribution of complex dielectric constant in the microwave frequency band measurement area is obtained: e M =e' M -yes" M In the formula, ε M is the complex dielectric constant in the microwave frequency band, ε' M is the real part of the effective dielectric constant of the mixture in the microwave frequency band, ε” M is the imaginary part of the equivalent dielectric constant of the mixture in the microwave frequency band, and i is the imaginary unit.

3. The method for measuring flow parameters of gas-solid two-phase flow according to claim 1, characterized in that: The method to correct the assumed particle moisture to meet the comparison value is: Set the contrast value δ; Compare the microwave attenuation calculated under the complex dielectric constant distribution with the microwave attenuation actually measured. If α N >α 0 Increase the water content W N , if α N <α 0 Then reduce the water content W N , the microwave attenuation under the complex dielectric constant distribution is repeatedly calculated until |α N -α 0 |<δ converges; After convergence is met, the particle concentration distribution and moisture content are output.

4. The method for measuring flow parameters of gas-solid two-phase flow according to claim 3, characterized in that: The contrast value δ is 0.1% to 0.5%.

5. The method for measuring flow parameters of gas-solid two-phase flow according to claim 1, characterized in that: The method of obtaining the capacitance vector of the area to be measured and reconstructing the real dielectric constant distribution of the area to be measured is based on the mapping relationship between the dielectric constant and the capacitance vector.

6. The method for measuring flow parameters of gas-solid two-phase flow according to claim 5, characterized in that: The mapping relationship between the dielectric constant and the capacitance vector is abstracted as: λ=S·g Where λ is the normalized capacitance vector, S is the sensitive field matrix, and g is the normalized dielectric constant.

7. The method for measuring flow parameters of gas-solid two-phase flow according to claim 6, characterized in that: According to the mapping relationship between the dielectric constant and the capacitance vector, an approximate estimate of the dielectric constant is obtained. The approximate estimate of the normalized dielectric constant obtained through the above reconstruction process is Then, through the inverse process of normalization, it is restored to the true real dielectric constant distribution ε'0.

8. An electronic device, characterized in that: include: one or more processors; A memory for storing one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors implement the gas-solid two-phase flow parameter measurement method according to any one of claims 1 to 7.

9. A storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the gas-solid two-phase flow parameter measurement method according to any one of claims 1 to 7 is implemented.

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