A liquid-solid two-phase flow measurement method based on acoustic-electric dual-mode fusion

Abstract

The present invention relates to a liquid-solid two-phase flow measurement method of acoustic-electric dual-mode sensor fusion, which is used to realize non-disturbance measurement of liquid-solid two-phase flow in a horizontal measurement pipeline. The sensors adopted include a dual-section resistance tomography sensor and a pulse wave ultrasonic Doppler sensor. The dual-section resistance tomography sensor is used to obtain the distribution of liquid-solid two-phase media in the pipeline and the flow velocity measurement of the bottom particle layer. The pulse wave ultrasonic Doppler sensor is used to obtain discrete phase flow velocity profile information. The flow velocity profile information measured under different flow states is converted into liquid-solid two-phase flow through interpolation-type integration.

Description

Technical Field

[0001] The invention belongs to the technical field of fluid measurement, and relates to a liquid-solid two-phase flow measurement method integrating an electrical and ultrasonic dual-modal sensor, which is used for realizing non-disturbance measurement of the liquid-solid two-phase flow. Background Art

[0002] Liquid-solid two-phase flow is widely present in the fields of chemical, pharmaceutical, refrigeration, food, etc. It is a common flow state in industrial production processes. The acquisition of two-phase flow parameters is helpful for numerical modeling verification and flow process analysis. Flow rate, as an important flow parameter of liquid-solid two-phase flow, is closely related to the two-phase flow state. The online and accurate measurement of flow rate plays a vital role in the monitoring of complex liquid-solid two-phase flow processes and the study of flow mechanism.

[0003] The main methods for measuring liquid-solid two-phase flow rate include electromagnetic flowmeter method, differential pressure method, Coriolis mass flowmeter method, correlation method, Doppler method, etc. As the most commonly used two-phase flow measurement method, the electromagnetic flowmeter method uses the principle of electromagnetic induction to measure the flow rate of the conductive fluid based on the electromotive force generated by the conductive fluid through the external magnetic field. It has the advantages of simple device structure and no pressure loss. The differential pressure method, such as the Venturi tube, uses the change in the pressure drop before and after the throttling device to establish a relationship with the fluid flow rate and solid phase concentration for measurement. It has the advantages of simplicity, low cost and high measurement accuracy. The Coriolis mass flowmeter is an instrument based on the principle of Coriolis force. By measuring the Coriolis force generated in the vibrating pipeline, the mass flow rate of the force-bearing fluid is proportional to the flow rate, and then the flow value is obtained. The measurement principle of the correlation method is to use the correlation of the signals collected by the upstream and downstream same-mode sensors (such as electrical, ray, ultrasound, etc.), obtain the time delay information according to the cross-correlation algorithm, and measure the flow rate (flow rate) in combination with the distance between the upstream and downstream sensors. Its measurement principle is simple and easy to implement. The Doppler method (laser, ultrasound) is based on the Doppler principle for flow measurement. There is a relative motion between the moving discrete phase in the fluid and the signal emission source. The echo signal reflected by the discrete phase and the reflected signal produce a Doppler frequency shift, which is proportional to the movement speed of the discrete phase. Combined with different echo signal times, the velocity profile information at different measurement positions can be obtained, thereby realizing flow measurement.

[0004] The above measurement methods all have their limitations, such as measurement errors for liquid-solid two-phase fluids with longitudinal asymmetric concentration and velocity distribution, sensor structure affecting the two-phase flow state and easily causing blockage, poor applicability for non-transparent, high-concentration liquid-solid two-phase flow, etc. The patent of this invention combines electrical tomography and ultrasonic Doppler non-perturbation measurement technology, uses multi-sensor measurement data to obtain pipeline cross-section concentration distribution and velocity distribution information, and uses fusion methods to obtain velocity profile measurement values ​​under different flow states, so as to achieve accurate measurement of liquid-solid two-phase flow. Summary of the invention

[0005] The present invention aims at the problem of measuring liquid-solid two-phase flow with longitudinal asymmetric concentration and velocity distribution, and provides a non-disturbance measurement method of acoustic-electric dual-mode fusion that can improve measurement accuracy. The technical solution of the present invention is as follows:

[0006] A liquid-solid two-phase flow measurement method using acoustic-electric dual-modal sensor fusion is used to achieve non-disturbance measurement of liquid-solid two-phase flow in a horizontal measurement pipeline. The sensors used include a dual-section electrical resistance tomography sensor and a pulse wave ultrasonic Doppler sensor. The dual-section electrical resistance tomography sensor is used to obtain the distribution of liquid-solid two-phase media in the pipeline and the flow velocity measurement of the bottom particle layer. The pulse wave ultrasonic Doppler sensor is used to obtain discrete phase velocity profile information. The method is characterized in that the velocity profile information measured under different flow states is converted into liquid-solid two-phase flow by a layered integration method, and the method comprises the following steps:

[0007] (1) collecting measurement signals of a dual-section electrical resistance tomography sensor and a pulse wave ultrasonic Doppler sensor, wherein the measurement data of each section of the dual-section electrical resistance tomography sensor is the boundary voltage in the adjacent excitation-measurement mode, and the measurement data of the pulse wave ultrasonic Doppler sensor is the echo signal of the pulse wave ultrasonic Doppler sensor received by the sensor after being reflected by discrete particles after passing through the liquid-solid two-phase flow;

[0008] (2) The resistance tomography sensor is used to identify the flow pattern of the liquid-solid two-phase flow. The measurement data of the resistance tomography sensor is combined with the tomography inversion algorithm Tikhonov algorithm to reconstruct the conductivity distribution information of the measured pipeline section, that is, the liquid-solid two-phase medium distribution reconstructed image. The reconstructed image pixel value represents the concentration value, and then the concentration values ​​at different positions of the pipeline section are obtained. The direction of the line connecting the upper and lower ends of the horizontal measurement pipeline is called the longitudinal direction. The longitudinal average concentration value is obtained by averaging the longitudinal direction. The longitudinal average concentration value is taken as the signal sequence, and its derivative is used to obtain the pipeline longitudinal concentration change rate γ(b):

[0009]

[0010] Where b is the longitudinal coordinate of the pipe section, and n is the number of longitudinal pixels;

[0011] When the rate of change of the longitudinal concentration of the pipeline If the following conditions are met, it is considered to conform to the longitudinal concentration variation law of liquid-solid two-phase flow heterogeneous flow, and the liquid-solid two-phase flow is identified as heterogeneous flow:

[0012]

[0013] In the formula, α is the liquid-solid two-phase flow longitudinal concentration change rate parameter, the height of the heterogeneous flow concentration boundary line from the bottom of the pipe is h,

[0014]

[0015] Where R is the radius of the horizontal measurement pipeline, and s is the vertical coordinate value of the pixel point at the center of the concentration boundary line from the bottom of the pipeline. Its value satisfies the following conditions:

[0016]

[0017] Where β is the longitudinal concentration parameter of the liquid-solid two-phase flow. After obtaining the concentration boundary line, proceed to step (3);

[0018] When the change rate of the longitudinal concentration change rate does not meet the above conditions, the liquid-solid two-phase flow is identified as a homogeneous flow and the process goes to step (4);

[0019] (3) When the liquid-solid two-phase flow pattern is identified as heterogeneous flow, the measurement data of the dual-section electrical resistance tomography sensor is used to form time series measurement data. The data dimension reduction feature extraction algorithm is used to convert the high-dimensional measurement data into low-dimensional feature data for cross-correlation processing. The flow velocity U of the bottom particle layer of the heterogeneous flow is obtained through cross-correlation algorithm processing. cc , after obtaining the flow rate of the particle layer at the bottom of the heterogeneous flow, proceed to step (5);

[0020] (4) The velocity profile of the discrete phase in the liquid-solid two-phase flow is measured by a pulse wave ultrasonic Doppler sensor. According to the Doppler principle, the echo signal contains the Doppler frequency shift information of the moving discrete phase. According to the measurement position corresponding to different measurement times, the echo signal is processed in segments, and the average frequency shift of different pulse repetition periods is taken as the average Doppler frequency shift of the measurement position. The flow velocity U(y) of the discrete solid phase particles at different positions is obtained by averaging the Doppler frequency shift;

[0021] (5) The longitudinal velocity profiles under different flow states are measured as follows: the velocity profile of the liquid-solid two-phase homogeneous flow is measured by the pulse wave ultrasonic Doppler in step (4) to obtain U(y); the velocity profile of the liquid-solid two-phase heterogeneous flow is the acoustic-electric dual-mode fusion velocity profile U m (y), which consists of two parts. The velocity value of the velocity profile above the concentration boundary is measured by the pulse wave ultrasonic Doppler sensor method in step (4), and the velocity value of the velocity profile below the concentration boundary is the velocity U of the particle layer at the bottom of the heterogeneous flow in step (3). cc ;

[0022]

[0023] (6) The longitudinal velocity profile information is converted into cross-sectional average velocity information to achieve the measurement of liquid-solid two-phase flow rate Q as follows:

[0024] 1) The pipe section is divided into N areas along the longitudinal direction according to the number of measurement points N of the longitudinal velocity profile. The longitudinal height of each area is equal, and the area of ​​the area is A(y). The calculation formula is as follows:

[0025]

[0026]

[0027] Where Q(y) is the flow value of the area y away from the bottom, and A(y) is the area of ​​the area y away from the bottom;

[0028] 2) The Newton-Cotes formula is used to solve the liquid-solid two-phase flow rate Q by interpolation integral.

[0029] Preferably, in step (2), α is taken as 3; β is the longitudinal concentration parameter of the liquid-solid two-phase flow and is taken as 4.

[0030] Preferably, the method of step (3) is as follows:

[0031] 1) Extract boundary voltage characteristic parameters:

[0032]

[0033] Where V R (t) is the characteristic parameter vector of the boundary voltage of the resistance tomography sensor at time t, V ij is the boundary voltage of the jth electrode pair when the liquid-solid two-phase fluid is excited by the i-th electrode pair, V ij0 is the boundary voltage of the ith electrode pair in the pure liquid phase when the jth electrode pair is excited;

[0034] 2) The time series measurement data of the dual-section resistance tomography sensor is processed by the cross-correlation algorithm to obtain the cross-correlation delay τ,

[0035] 3) Flow velocity U of the particle layer at the bottom of heterogeneous flow cc for,

[0036]

[0037] Where D is the distance between the dual-section RTS sensors.

[0038] Preferably, in step (4), the flow velocity U(y) of the discrete solid phase particles is calculated as follows:

[0039]

[0040]

[0041] In the formula, is the average Doppler frequency shift at a distance y from the bottom of the pipeline, f d (y) pis the Doppler frequency shift at a distance y from the bottom within the pth pulse repetition period, q is the number of pulse repetition periods used to calculate the velocity profile, and c 0 is the speed of sound in the pulsed wave ultrasound Doppler mounting wedge, θ 0 is the angle between the normal direction of the ultrasonic sensor element in the wedge and the fluid flow direction, thereby obtaining the longitudinal flow velocity profile of the pipeline.

[0042] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0043] 1. This method is a non-disturbance measurement method, which uses an acoustic and electrical dual-mode sensor for measurement and does not affect the flow of the fluid;

[0044] 2. Measure liquid-solid two-phase fluids in different flow states to reduce the measurement error caused by the longitudinal asymmetric concentration and velocity profile caused by the flow state;

[0045] 3. Simple installation, fast measurement speed, low cost, and can accurately measure the liquid-solid two-phase flow in the pipeline. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The following drawings describe selected embodiments of the present invention, which are exemplary drawings and are not exhaustive or limiting, wherein:

[0047] Figure 1 It is a flow chart of liquid-solid two-phase flow measurement in the measurement method of the present invention;

[0048] Figure 2 It is a schematic diagram of the pipeline installation of the acoustic-electric dual-mode sensor in the measurement method of the present invention;

[0049] Figure 3 A schematic diagram of obtaining a longitudinal average concentration by an electrical resistance tomography sensor in the measurement method of the present invention;

[0050] Figure 4 It is a schematic diagram of the measurement principle of the cross-correlation algorithm of the dual-section electrical resistance tomography sensor in the measurement method of the present invention;

[0051] Figure 5 It is a schematic diagram of cross-sectional flow velocity measurement using the layered integration method in the measurement method of the present invention;

[0052] Figure 6 It is a real picture of different flow states of liquid-solid two-phase flow in the measurement method of the present invention;

[0053] Figure 7 It is the liquid-solid two-phase flow measurement result and relative measurement error diagram in the measurement method of the present invention. DETAILED DESCRIPTION

[0054] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0055] In this example, the sand-water two-phase flow in the horizontal measurement pipeline is taken as the liquid-solid two-phase research object. The ultrasonic and electrical dual-mode sensor fusion method is used to realize the non-disturbance measurement of the flow rate under different flow states of the liquid-solid two-phase flow. The dual-section resistance tomography sensor obtains the distribution of the liquid-solid two-phase medium in the pipeline and the flow velocity measurement of the bottom particle layer. The pulse wave ultrasonic Doppler sensor obtains the discrete phase velocity profile information. The velocity profile information measured under different flow states is converted into liquid-solid two-phase flow through the layered integration method. The specific measurement process is as follows: Figure 1 The liquid-solid two-phase flow measurement method of acoustic-electric dual-mode fusion includes the following steps:

[0056] Step 1: According to Figure 2 The acoustic-electric dual-mode sensor pipeline installation method shown in the figure is to install a dual-section 16-electrode resistance tomography sensor and a pulse wave ultrasonic Doppler sensor, and collect 10s of acoustic-electric dual-mode sensor measurement data, wherein the measurement data of the resistance tomography sensor is the boundary voltage under adjacent excitation-measurement modes, and the measurement data of the pulse wave ultrasonic Doppler sensor is the echo signal of the pulse wave ultrasonic Doppler sensor received by the sensor after being reflected by discrete particles after passing through the liquid-solid two-phase flow;

[0057] Step 2: The measurement data of the electrical resistance tomography sensor is combined with the tomography inversion algorithm Tikhonov algorithm (Yang WQ, Peng L. Image reconstruction algorithms for electrical capacitancetomography, Measurement science and technology, 2002, 14 (1): R1. pp. 1-13 or Tikhonov A. N. Solution of incorrectly formulated problems and the regularization method, Soviet Mathematic Doklady, 1963, 4. pp. 1035–1038) to reconstruct the conductivity distribution information of the measured pipe section, that is, the liquid-solid two-phase medium distribution reconstruction image, and filtering is performed to eliminate measurement noise. The pixel value of the reconstructed image represents the concentration value, and then the concentration value P (a, b) at different positions of the pipe section is obtained. The concentration value of the pipe section is normalized to obtain P s (a, b);

[0058]

[0059] Where a and b are the coordinates of the cross section. The direction of the line connecting the upper and lower ends of the horizontal measurement pipeline is called the longitudinal direction, and the direction of the line connecting the left and right ends is called the transverse direction. The longitudinal average concentration value is obtained by longitudinal averaging. like Figure 3 As shown;

[0060]

[0061] Where m is the number of horizontal pixels in the pipe section, and n is the number of vertical pixels. The longitudinal average concentration value is used as the signal sequence, and its derivative is used to obtain the longitudinal concentration change rate γ(b):

[0062]

[0063] When the rate of change of the longitudinal concentration of the pipeline If the following conditions are met, it is considered to conform to the longitudinal concentration variation law of liquid-solid two-phase flow heterogeneous flow, and the liquid-solid two-phase flow is identified as heterogeneous flow.

[0064]

[0065] Where α is the liquid-solid two-phase flow longitudinal concentration change rate parameter, which is 3. The heterogeneous flow concentration boundary is as follows: Figure 3 As shown by the dotted line, the height h of the dividing line from the bottom of the pipe is,

[0066]

[0067] Where R is the radius of the horizontal measurement pipeline, and s is the vertical coordinate value of the pixel point at the center of the concentration boundary line from the bottom of the pipeline. Its value satisfies the following conditions:

[0068]

[0069] Where β is the longitudinal concentration parameter of liquid-solid two-phase flow, which takes a value of 4. After obtaining the concentration boundary line, proceed to step 3.

[0070] When the change rate of the longitudinal concentration change rate does not meet the above conditions, the liquid-solid two-phase flow is identified as a homogeneous flow and the process goes to step 4;

[0071] Step 3: Use the measurement data of the dual-section electrical resistance tomography sensor to form time series measurement data, and use the data dimension reduction feature extraction algorithm to convert the high-dimensional measurement data into low-dimensional feature data for cross-correlation processing. The velocity of the bottom particle layer of the heterogeneous flow is obtained through the cross-correlation algorithm. The measurement principle is as follows: Figure 4 The boundary voltage characteristic parameter extraction method is as follows:

[0072]

[0073] Where V R (t) is the characteristic parameter vector of the boundary voltage of the resistance tomography sensor at time t, V ij is the boundary voltage of the jth electrode pair when the liquid-solid two-phase fluid is excited by the i-th electrode pair, V ij0 is the boundary voltage of the ith electrode pair in the pure liquid phase when the jth electrode pair is excited.

[0074] The time series measurement data of the dual-section resistance tomography sensor are processed by the cross-correlation algorithm. The cross-correlation function is as follows:

[0075]

[0076] Where V R1 (t) and V R2 (t) are the characteristic parameter vectors of boundary voltage characteristics of section 1 and section 2 at time t, τ is the cross-correlation delay, and T is the cross-correlation integration time.

[0077] The velocity of the particle layer at the bottom of the heterogeneous flow U cc for,

[0078]

[0079] Where D is the distance between the dual-section electrical resistance tomography sensors. After obtaining the flow velocity of the bottom granular layer, proceed to step 5.

[0080] Step 4: Directly obtain the discrete phase velocity profile in the liquid-solid two-phase flow through the pulse wave ultrasonic Doppler echo signal. According to the Doppler principle, the echo signal contains the Doppler frequency shift information of the moving discrete phase. According to the different time delays ξ in the echo signal and the distance of the corresponding spatial point relative to the bottom,

[0081]

[0082] Where ξ is the time delay, y is the distance relative to the bottom, c is the speed of sound in the fluid, and θ is the angle between the direction of the ultrasonic wave entering the fluid and the direction of the fluid flow.

[0083] The Doppler frequency shift information is extracted by processing the pulse wave ultrasonic Doppler echo signal through multiplication demodulation or spectrum analysis. According to the measurement position corresponding to different measurement times, the echo signal is processed in segments, and the average frequency shift of different pulse repetition periods is taken as the average Doppler frequency shift of the measurement position. The flow velocity U(y) of discrete solid particles at different positions is obtained by averaging the Doppler frequency shift. The calculation formula is as follows:

[0084]

[0085]

[0086] In the formula, is the average Doppler shift at a distance y from the bottom, f d (y) p is the Doppler frequency shift at a distance y from the bottom within the pth pulse repetition period, q is the number of pulse repetition periods used to calculate the velocity profile, and c 0 is the speed of sound in the pulsed wave ultrasound Doppler mounting wedge, θ 0 is the angle between the normal direction of the ultrasonic sensor element in the wedge and the fluid flow direction, thereby obtaining the longitudinal flow velocity profile of the pipeline;

[0087] Step 5: Measure the longitudinal velocity profile under different flow states. The velocity profile of the liquid-solid two-phase homogeneous flow is measured by the pulse wave ultrasonic Doppler in step 4 to obtain U(y); the velocity profile of the liquid-solid two-phase heterogeneous flow is the acoustic-electric dual-mode fusion velocity profile U m (y), which consists of two parts. The velocity value of the velocity profile above the concentration boundary is measured by the pulse wave ultrasonic Doppler sensor method in step 4, and the velocity value of the velocity profile below the concentration boundary is the velocity U of the particle layer at the bottom of the heterogeneous flow in step 3. cc ;

[0088]

[0089] Step 6: Use the layered integration method to convert the longitudinal velocity profile information into cross-sectional average velocity information to achieve the measurement of liquid-solid two-phase flow Q. The pipe cross section is divided into N regions along the longitudinal direction by the number of measurement points N of the longitudinal velocity profile. The longitudinal height of each region is equal, and the area of ​​the region is A(y), as shown in Figure 5 As shown, the liquid-solid two-phase flow rate is obtained by the layered integration method. The calculation formula is as follows:

[0090]

[0091]

[0092] Where Q(y) is the flow rate of the area y away from the bottom, and A(y) is the area of ​​the area y away from the bottom.

[0093] The Newton-Cotes formula is used to solve the liquid-solid two-phase flow rate by interpolation integral.

[0094]

[0095]

[0096] y k =kl

[0097] In the formula, is the Cotes coefficient, l is the step size, y k For equidistant nodes, the Cotes coefficient is calculated as follows, transforming y k =κl,

[0098]

[0099] The liquid-solid two-phase flow rate Q is obtained through calculation.

[0100] Figure 6 Actual flow diagram of different flow states of liquid-solid two-phase flow captured by a high-speed camera.

[0101] Figure 7 The measurement results and relative error diagram of the acoustic-electric dual-mode fusion liquid-solid two-phase flow measurement method of the present invention are shown in Figure 1. The measurement error analysis shows that the present invention has good measurement accuracy, which proves the effectiveness of the present invention.

[0102] The above description of the present invention and its implementation is not limited thereto, and the accompanying drawings are only one of the implementations of the present invention. Without departing from the purpose of the present invention, any uninventively designed embodiment similar to the technical solution shall fall within the protection scope of the present invention.

Claims

1. A liquid-solid two-phase flow measurement method using acoustic-electric dual-modal sensor fusion is used to achieve non-disturbance measurement of liquid-solid two-phase flow in a horizontal measurement pipeline. The sensors used include a dual-section electrical resistance tomography sensor and a pulse wave ultrasonic Doppler sensor. The dual-section electrical resistance tomography sensor is used to obtain the distribution of liquid-solid two-phase media in the pipeline and the flow velocity measurement of the bottom particle layer. The pulse wave ultrasonic Doppler sensor is used to obtain discrete phase flow velocity profile information. It is characterized in that The velocity profile information measured under different flow states is converted into liquid-solid two-phase flow rate through interpolation integration, which includes the following steps: (1) collecting measurement signals of a dual-section electrical resistance tomography sensor and a pulse wave ultrasonic Doppler sensor, wherein the measurement data of each section of the dual-section electrical resistance tomography sensor is the boundary voltage in the adjacent excitation-measurement mode, and the measurement data of the pulse wave ultrasonic Doppler sensor is the echo signal of the pulse wave ultrasonic Doppler sensor received by the sensor after being reflected by discrete particles after passing through the liquid-solid two-phase flow; (2) The resistance tomography sensor is used to identify the flow pattern of the liquid-solid two-phase flow. The measurement data of the resistance tomography sensor is combined with the tomography inversion algorithm Tikhonov algorithm to reconstruct the conductivity distribution information of the measured pipeline section, that is, the liquid-solid two-phase medium distribution reconstructed image. The reconstructed image pixel value represents the concentration value, and then the concentration values ​​at different positions of the pipeline section are obtained. The direction of the line connecting the upper and lower ends of the horizontal measurement pipeline is called the longitudinal direction. The longitudinal average concentration value is obtained by averaging the longitudinal direction. The longitudinal average concentration value is taken as the signal sequence, and its derivative is used to obtain the pipeline longitudinal concentration change rate γ(b): Where b is the longitudinal coordinate of the pipe section, and n is the number of longitudinal pixels; When the rate of change of the longitudinal concentration of the pipeline If the following conditions are met, it is considered to conform to the longitudinal concentration variation law of liquid-solid two-phase flow heterogeneous flow, and the liquid-solid two-phase flow is identified as heterogeneous flow: In the formula, α is the liquid-solid two-phase flow longitudinal concentration change rate parameter, the height of the heterogeneous flow concentration boundary line from the bottom of the pipe is h, Where R is the radius of the horizontal measurement pipeline, and s is the vertical coordinate value of the pixel point at the center of the concentration boundary line from the bottom of the pipeline. Its value satisfies the following conditions: Where β is the longitudinal concentration parameter of the liquid-solid two-phase flow. After obtaining the concentration boundary line, proceed to step (3); When the change rate of the longitudinal concentration change rate does not meet the above conditions, the liquid-solid two-phase flow is identified as a homogeneous flow and the process goes to step (4); (3) When the liquid-solid two-phase flow pattern is identified as heterogeneous flow, the measurement data of the dual-section electrical resistance tomography sensor is used to form time series measurement data. The data dimension reduction feature extraction algorithm is used to convert the high-dimensional measurement data into low-dimensional feature data for cross-correlation processing. The flow velocity U of the bottom particle layer of the heterogeneous flow is obtained through cross-correlation algorithm processing. cc , after obtaining the flow rate of the particle layer at the bottom of the heterogeneous flow, proceed to step (5); (4) The velocity profile of the discrete phase in the liquid-solid two-phase flow is measured by a pulse wave ultrasonic Doppler sensor. According to the Doppler principle, the echo signal contains the Doppler frequency shift information of the moving discrete phase. According to the measurement position corresponding to different measurement times, the echo signal is processed in segments, and the average frequency shift of different pulse repetition periods is taken as the average Doppler frequency shift of the measurement position. The flow velocity U(y) of the discrete solid phase particles at different positions is obtained by averaging the Doppler frequency shift; (5) The longitudinal velocity profiles under different flow states are measured as follows: the velocity profile of the liquid-solid two-phase homogeneous flow is measured by the pulse wave ultrasonic Doppler in step (4) to obtain U(y); the velocity profile of the liquid-solid two-phase heterogeneous flow is the acoustic-electric dual-mode fusion velocity profile U m (y), which consists of two parts. The velocity value of the velocity profile above the concentration boundary is measured by the pulse wave ultrasonic Doppler sensor method in step (4), and the velocity value of the velocity profile below the concentration boundary is the velocity U of the particle layer at the bottom of the heterogeneous flow in step (3). cc ; (6) The longitudinal velocity profile information is converted into cross-sectional average velocity information to achieve the measurement of liquid-solid two-phase flow rate Q as follows: 1) The pipe section is divided into N areas along the longitudinal direction according to the number of measurement points N of the longitudinal velocity profile. The longitudinal height of each area is equal, and the area of ​​the area is A(y). The calculation formula is as follows: Where Q(y) is the flow value of the area y away from the bottom, and A(y) is the area of ​​the area y away from the bottom; 2) The Newton-Cotes formula is used to solve the liquid-solid two-phase flow rate Q by interpolation integral.

2. The liquid-solid two-phase flow measurement method of the acoustic-electric dual-modal sensor fusion according to claim 1, It is characterized in that In step (2), α is taken as 3; β is the longitudinal concentration parameter of liquid-solid two-phase flow and its value is 4.

3. The liquid-solid two-phase flow measurement method of the acoustic-electric dual-modal sensor fusion according to claim 1, It is characterized in that The method of step (3) is as follows: 1) Extract boundary voltage characteristic parameters: Where V R (t) is the characteristic parameter vector of the boundary voltage of the resistance tomography sensor at time t, V ij is the boundary voltage of the jth electrode pair when the liquid-solid two-phase fluid is excited by the i-th electrode pair, V ij0 is the boundary voltage of the jth electrode pair when the i-th electrode pair is excited in the pure liquid phase; 2) The time series measurement data of the dual-section resistance tomography sensor is processed by the cross-correlation algorithm to obtain the cross-correlation delay τ, 3) Flow velocity U of the particle layer at the bottom of heterogeneous flow cc for, Where D is the distance between the dual-section RTS sensors.

4. The liquid-solid two-phase flow measurement method of the acoustic-electric dual-modal sensor fusion according to claim 1, It is characterized in that In step (4), the flow velocity U(y) of the discrete solid phase particles is calculated as follows: In the formula, is the average Doppler frequency shift at a distance y from the bottom of the pipeline, f d (y) p is the Doppler frequency shift at a distance y from the bottom within the pth pulse repetition period, q is the number of pulse repetition periods used to calculate the velocity profile, and c 0 is the speed of sound in the pulsed wave ultrasound Doppler mounting wedge, θ 0 is the angle between the normal direction of the ultrasonic sensor element in the wedge and the fluid flow direction, thereby obtaining the longitudinal flow velocity profile of the pipeline.

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