A method and system for synchronously reconstructing the morphology and field distribution of mixed particle two-phase flow

Abstract

The disclosed embodiments relate to the technical field of flow process parameter detection by ultrasonic tomography, and provide a method and system for synchronous reconstruction of the morphology and field distribution of a mixed particle two-phase flow, the method comprising: obtaining ultrasonic signal projection data of the mixed particle two-phase flow; determining a grid image of a transducer array corresponding to the ultrasonic signal projection data; respectively determining sensitive intervals of each ultrasonic projection path in the transducer array in the grid image; determining a weight value of each grid in each sensitive interval based on the ultrasonic signal projection data; reconstructing the grid image based on the weight value of each grid in the sensitive interval to obtain a morphology and field distribution image corresponding to the mixed particle two-phase flow. The disclosed embodiments not only realize the synchronous reconstruction of the morphology and field distribution of large particle and small particle dispersion systems in the mixed particle two-phase flow, but also effectively improve the reconstruction efficiency and detection efficiency of the morphology and field distribution image of the mixed particle two-phase flow, and have high practicality.

Description

Technical Field

[0001] The present disclosure relates to the technical field of flow process parameter detection of ultrasonic tomography, and in particular to a method and system for synchronously reconstructing the morphology and field distribution of a mixed particle two-phase flow. Background Art

[0002] Particle two-phase flow is widely present in nature, and is also commonly found in industrial production and people's daily lives. The distribution of phase interfaces, i.e., the identification of flow patterns, is widely present in industrial processes such as metallurgy, chemical industry, and petroleum transportation. Existing ultrasonic tomography technology can provide a visual distribution of components in a flow channel or container, and can be widely used in various research fields in various forms, especially in the study of the spatial and temporal distribution of particles in a flow field.

[0003] A two-phase flow system usually includes a discrete phase and a background phase. The background phase carries the flow of particles and can be water or air. The substance that exists in the continuous phase in the form of bubbles, solid particles, etc. is called a discrete phase. According to the characteristics of the discrete phase, the particle two-phase flow can be divided into three categories, including large particle flow, small particle dispersion system, and mixed particle two-phase flow. Among them, when the macroscopic size of the particle is much larger than the wavelength of the sound wave in the medium, the sound wave will form an obvious sound shadow area behind the particle after projecting on the particle. At this time, the particle two-phase flow meets the characteristics of the first category, namely large particle flow. When the macroscopic size of the particle is much smaller than the wavelength of the sound wave or close to the wavelength of the sound wave, the second object, a small particle dispersion system, will be derived. The distribution characteristics of small particle dispersion systems are often the focus of existing technical research.

[0004] In addition to the above two situations, the third type of particle two-phase flow is mixed particle two-phase flow, which contains both large particle and small particle dispersions. For example: a non-uniform particle suspension will suddenly produce obvious bubbles during the flow process. The bubbles belong to large particles, while the particle suspension belongs to a small particle dispersion. For another example, when coal powder particles are distributed in the nested pipe interlayer, the inner tube belongs to large particles, and the coal powder particles belong to a small particle dispersion. Therefore, how to reconstruct the field distribution of the small particle dispersion in the mixed particle two-phase flow and reconstruct the sparse large particle morphology in the mixed particle two-phase flow has become an urgent problem to be solved in this field. Summary of the invention

[0005] The present disclosure aims to solve at least one of the problems existing in the prior art and to provide a method and system for synchronously reconstructing the morphology and field distribution of a mixed particle two-phase flow.

[0006] In one aspect of the present disclosure, a method for synchronously reconstructing the morphology and field distribution of a mixed particle two-phase flow is provided, the synchronous reconstruction method comprising:

[0007] Acquire ultrasonic signal projection data of mixed particle two-phase flow;

[0008] Determining a grid image of a transducer array corresponding to the ultrasound signal projection data;

[0009] respectively determining sensitive intervals of each ultrasound projection path in the transducer array in the grid image;

[0010] Determining a weight value of each grid in each sensitive interval based on the ultrasound signal projection data;

[0011] Based on the weight value of each grid in the sensitive interval, the grid image is reconstructed to obtain the morphology and field distribution image corresponding to the mixed particle two-phase flow.

[0012] Optionally, the acquiring of ultrasonic signal projection data of mixed particle two-phase flow includes:

[0013] collecting and processing the ultrasonic signal amplitude of the background phase in the mixed particle two-phase flow;

[0014] Based on the ultrasonic signal amplitude of the background phase, ultrasonic signal collection and preprocessing are performed on the mixed particles in the mixed particle two-phase flow to obtain ultrasonic signal values ​​on each of the ultrasonic projection paths.

[0015] Optionally, in the mixed particle two-phase flow, the ultrasonic signal value on each ultrasonic projection path is expressed as Formula 1:

[0016] Formula 1;

[0017] in, represents the ultrasound projection path T x -R y The ultrasonic signal value on represents the ultrasound projection path T x -R y The ultrasonic signal amplitude of the upper background phase, represents the ultrasound projection path T x -R y The amplitude of the ultrasonic transmission attenuation signal in the small particle dispersion system is represents the sound transmission coefficient, T x represents the ultrasonic emission point with serial number x, R y Indicates the ultrasonic receiving point with serial number y.

[0018] Optionally, the sound transmission coefficient Expressed as formula 2:

[0019] Formula 2;

[0020] in, represents the ultrasonic incident angle, represents the ultrasonic refraction angle, represents the acoustic impedance of large particles, Represents the acoustic impedance of the background phase.

[0021] Optionally, the ultrasound projection path T x -R y The sensitive interval in the grid image includes the midpoint T of the first ultrasound transmission interval x-0.5 , the midpoint of the second ultrasonic emission interval T x+0.5 and the ultrasonic receiving point R y The previous ultrasonic receiving point R y-1 , Ultrasonic receiving point R y The next ultrasonic receiving point R y+1 The trapezoidal area is composed of a first ultrasonic transmission interval midpoint T x-0.5 is the ultrasonic emission point T x The previous ultrasonic emission point T x-1 The midpoint of the interval of the second ultrasonic emission interval is T x+0.5 is the ultrasonic emission point T x The next ultrasonic emission point T x+1 The midpoint of the interval.

[0022] Optionally, determining the weight value of each grid in each sensitive interval based on the ultrasound signal projection data includes:

[0023] If the ultrasonic signal value If the value is 0, the ultrasound projection path T x -R y The weight values ​​of all grids in the sensitive interval in the grid image are set to a first weight value;

[0024] If the ultrasonic signal value The value is , then the ultrasound projection path T x -R y The weight value of each grid in the sensitive interval in the grid image is set to a second weight value determined by a linear back-projection method;

[0025] If the ultrasonic signal value If the value is 1, the ultrasound projection path T x -R y The weight values ​​of all grids in the sensitive interval in the grid image are set to a third weight value;

[0026] The first weight value is less than the third weight value, and the third weight value is less than or equal to the ultrasonic signal value. The value is The minimum value of the second weight values ​​corresponding to each grid.

[0027] Optionally, the second weight value determined by the linear back projection method includes: The second weight value is determined, wherein represents the sensitivity coefficient matrix, represents the ultrasonic signal value matrix, A matrix representing the second weight values ​​corresponding to all grids in the grid image.

[0028] Optionally, the reconstructing the grid image based on the weight value of each grid in the sensitive interval to obtain the morphology and field distribution image corresponding to the mixed particle two-phase flow includes:

[0029] The weight values ​​of each grid in the sensitive interval corresponding to each of the ultrasound projection paths are added up according to their positions to obtain the weight accumulation value corresponding to each grid in the grid image;

[0030] The weight accumulation values ​​corresponding to each grid in the grid image are converted into corresponding pixel values ​​to obtain the morphology and field distribution image.

[0031] Another aspect of the present disclosure provides a system for synchronously reconstructing the morphology and field distribution of a mixed particle two-phase flow, the synchronous reconstruction system comprising:

[0032] An acquisition module, used for acquiring ultrasonic signal projection data of mixed particle two-phase flow;

[0033] A first determination module, configured to determine a grid image of a transducer array corresponding to the ultrasound signal projection data;

[0034] A second determination module is used to respectively determine the sensitive intervals of each ultrasound projection path in the transducer array in the grid image;

[0035] A third determination module, configured to determine a weight value of each grid in each sensitive interval based on the ultrasound signal projection data;

[0036] The reconstruction module is used to reconstruct the grid image based on the weight value of each grid in the sensitive interval to obtain the morphology and field distribution image corresponding to the mixed particle two-phase flow.

[0037] Another aspect of the present disclosure provides an electronic device, including:

[0038] at least one processor; and,

[0039] a memory communicatively connected to at least one processor; wherein,

[0040] The memory stores instructions that can be executed by at least one processor, and the instructions are executed by at least one processor so that the at least one processor can execute the method for synchronously reconstructing the morphology and field distribution of the mixed particle two-phase flow described above.

[0041] Compared with the prior art, the present invention obtains ultrasonic signal projection data of mixed particle two-phase flow, and reconstructs the morphology and field distribution image corresponding to the mixed particle two-phase flow based on the ultrasonic signal projection data. This not only realizes the synchronous reconstruction of the morphology and field distribution of large particle and small particle dispersion systems in the mixed particle two-phase flow, but also effectively improves the reconstruction efficiency and detection efficiency of the morphology and field distribution image of the mixed particle two-phase flow, and has high practicality. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] One or more embodiments are exemplarily described by pictures in the corresponding drawings, and these exemplifications do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings represent similar elements, and unless otherwise stated, the figures in the drawings do not constitute proportional limitations.

[0043] Figure 1 A flow chart of a method for synchronously reconstructing the morphology and field distribution of a mixed particle two-phase flow provided in one embodiment of the present disclosure;

[0044] Figure 2 The ultrasound projection path T provided in another embodiment of the present disclosure is x -R y Schematic diagram of sensitive intervals in a grid image;

[0045] Figure 3 A flow chart of a method for synchronously reconstructing the morphology and field distribution of a mixed particle two-phase flow provided in another embodiment of the present disclosure;

[0046] Figure 4 The morphology and field distribution image corresponding to the mixed particle two-phase flow provided by another embodiment of the present disclosure;

[0047] Figure 5 A schematic diagram of the structure of a system for synchronously reconstructing the morphology and field distribution of a mixed particle two-phase flow provided by another embodiment of the present disclosure;

[0048] Figure 6 A schematic diagram of an application of a system for synchronously reconstructing the morphology and field distribution of a mixed particle two-phase flow provided by another embodiment of the present disclosure;

[0049] Figure 7 A schematic structural diagram of an electronic device provided in another embodiment of the present disclosure. DETAILED DESCRIPTION

[0050] In order to make the purpose, technical scheme and advantages of the embodiments of the present disclosure clearer, the embodiments of the present disclosure will be described in detail below in conjunction with the accompanying drawings. However, it can be understood by those skilled in the art that in each embodiment of the present disclosure, many technical details are proposed in order to enable readers to better understand the present disclosure. However, even without these technical details and various changes and modifications based on the following embodiments, the technical scheme claimed for protection in the present disclosure can also be implemented. The division of the following embodiments is for the convenience of description and should not constitute any limitation on the specific implementation of the present disclosure. The various embodiments can be combined and referenced with each other without contradiction.

[0051] One embodiment of the present disclosure relates to a method for synchronously reconstructing the morphology and field distribution of a mixed particle two-phase flow, the process of which is as follows: Figure 1 As shown, including:

[0052] Step S110, acquiring ultrasonic signal projection data of mixed particle two-phase flow.

[0053] Specifically, the mixed particle two-phase flow here contains both large particle and small particle dispersions. Large particles refer to particles whose macroscopic size is much larger than the wavelength of the sound wave in the medium. After the sound wave is projected on such particles, an obvious sound-generating shadow area will be formed behind the particles. For example, large particles can be bubbles. Small particles in the small particle dispersion refer to particles whose macroscopic size is much smaller than the wavelength of the sound wave in the medium or close to the wavelength of the sound wave in the medium. In other words, if the equivalent radius of a particle in the mixed particle two-phase flow is satisfy , represents the wavelength of the sound wave in the medium, then the particle is considered to be a large particle. When the wave number of the sound wave in the medium is recorded as k Sometimes, there is , If the equivalent radius of a particle in a mixed particle two-phase flow is Dissatisfied , then the particle is considered to be a small particle.

[0054] In step S110, when acquiring the ultrasonic signal projection data of the mixed particle two-phase flow, the ultrasonic signal projection data of the mixed particle two-phase flow may be acquired in advance, or the ultrasonic signal projection data of the mixed particle two-phase flow may be acquired in real time, and this embodiment is not limited thereto.

[0055] Exemplarily, step S110 includes: collecting and processing the ultrasonic signal amplitude of the background phase in the mixed particle two-phase flow; based on the ultrasonic signal amplitude of the background phase, collecting and preprocessing the ultrasonic signals of the mixed particles in the mixed particle two-phase flow to obtain the ultrasonic signal values ​​on each ultrasonic projection path.

[0056] Specifically, the background phase in the mixed particle two-phase flow only carries the flow of particles and does not contain any mixed particles, i.e., does not contain any large particles or small particles. Therefore, step S110 can respectively collect the ultrasonic signal amplitude of the background phase and the ultrasonic signal value of the mixed particles on each ultrasonic projection path.

[0057] Since the large particles and small particles in the mixed particle two-phase flow are two completely different objects, after collecting the ultrasonic signal amplitude of the background phase, step S110 can first collect and preprocess the ultrasonic signals of the mixed particle two-phase flow containing only the small particle dispersion but not the large particles, and then collect and preprocess the ultrasonic signals of the mixed particle two-phase flow containing both the small particle dispersion and the large particles. The processing of the ultrasonic signal utilizes the attenuation signal of the transmission wave passing through the test area.

[0058] For a mixed particle two-phase flow containing only small particle dispersions but no large particles, its ultrasonic projection path T x -R y Ultrasonic signal value on Expressed as ,in, represents the ultrasound projection path T x -R y The ultrasonic signal amplitude of the upper background phase, represents the ultrasound projection path T x -R y The amplitude of the ultrasonic transmission attenuation signal in the small particle dispersion, T x represents the ultrasonic emission point with serial number x, R y Indicates the ultrasound receiving point with serial number y. For the ultrasound signal of the background phase and the ultrasound transmission attenuation signal on the corresponding ultrasound projection path, if the ultrasound transmission attenuation signal is on the ultrasound projection path T x -R y Theoretically, and The ratio is 1. However, in practical applications, due to the signal fluctuations that may be caused by the signal excitation and signal conditioning circuits and the possible instability of the ultrasonic transducer itself, when the ultrasonic transmission attenuation signal is in the ultrasonic projection path T x -R y When only the background area is passed, and The ratio of usually fluctuates around the value 1. Through multiple tests, it is found that when the ultrasound transmission attenuation signal is in the ultrasound projection path T x -R y When only the background area is passed, and The ratio of is usually within ±8% of the value 1, so when and The ratio is in the range When The value is 1 to indicate that is the ultrasound projection path T x -R y The ultrasonic signal amplitude of the background phase is and When the ratio is greater than 1.08, The value is and The ratio of is the ultrasound projection path T x -R y The value of the ultrasonic signal when passing through a dispersion of small particles.

[0059] The ultrasonic projection path T in the mixed particle two-phase flow containing only small particle dispersions but not large particles is obtained. x -R y After the ultrasonic signal value is obtained, step S110 may be performed to collect and preprocess the ultrasonic signal of the mixed particle two-phase flow containing both the small particle dispersion and the large particles.

[0060] Exemplarily, for a mixed particle two-phase flow containing both small particle dispersion and large particles, the ultrasonic signal value on each ultrasonic projection path is expressed as Formula 1:

[0061] Formula 1.

[0062] in, represents the ultrasound projection path T x -R y The ultrasonic signal value on represents the ultrasound projection path T x -R y The ultrasonic signal amplitude of the upper background phase, represents the ultrasound projection path T x -R y The amplitude of the ultrasonic transmission attenuation signal in the small particle dispersion, T x represents the ultrasonic emission point with serial number x, R y Indicates the ultrasonic receiving point with serial number y, represents the sound transmission coefficient. It can provide signal processing threshold information to assist in determining the ultrasound projection path T x -R y Whether it passes through large particles. and The ratio is greater than or equal to , then it represents the ultrasound projection path Tx -R y After passing through the large particles in the mixed particle two-phase flow, at this time, the ultrasonic emission point T x The emitted ultrasonic signal will be blocked by large particles in the path, causing the ultrasonic receiving point R y Unable to receive the corresponding ultrasound signal, the ultrasound projection path T x -R y Ultrasonic signal value on The value is 0.

[0063] For example, the sound transmission coefficient Expressed as formula 2:

[0064] Formula 2.

[0065] in, represents the ultrasonic incident angle, represents the ultrasonic refraction angle, represents the acoustic impedance of large particles, Represents the acoustic impedance of the background phase.

[0066] Specifically, when the ultrasonic wave transitions from the first medium to the second medium with different acoustic properties, the boundary between the two media will produce acoustic reflection, so that only a part of the ultrasonic wave continues to propagate forward in the second medium. At this time, when the ultrasonic wave enters and leaves the boundary between the two media, the corresponding interface propagation direction satisfies .in, It represents the ultrasonic incident angle, that is, the angle when the ultrasonic wave enters the boundary of two media. It represents the refraction angle of ultrasonic wave, that is, the angle when ultrasonic wave leaves the boundary of two media. represents the propagation speed of ultrasonic waves in the first medium, It indicates the propagation speed of ultrasound in the second medium. Since the reflection angle caused by the reflected wave in the reflection phenomenon is the same as the ultrasonic incident angle, when the first medium is the background phase and the second medium is the large particles in the mixed particle two-phase flow, the acoustic reflection coefficient of the large particles is The reflected sound pressure The incident wave sound pressure The ratio of is described as .in, represents the acoustic impedance of large particles, represents the acoustic impedance of the background phase. The greater the difference between the acoustic impedance of the background phase and the acoustic impedance of the large particles, the more acoustic energy is reflected. Let the acoustic transmission coefficient , then , that is, the sound transmission coefficient It is expressed as the above formula 2.

[0067] Step S120: determining a grid image of the transducer array corresponding to the ultrasound signal projection data.

[0068] Specifically, the ultrasonic signal projection data of the mixed particle two-phase flow can be acquired by collecting several transducers in the transducer array. For example, when the mixed particle two-phase flow is located inside a pipeline, the transducer array can be arranged in a ring along the outer wall of the pipeline, and each transducer can sequentially serve as an ultrasonic emission point to emit ultrasonic signals, and the remaining transducers other than the transducer serving as the ultrasonic emission point serve as ultrasonic receiving points to receive ultrasonic signals, thereby realizing the ultrasonic signal projection data acquisition of the mixed particle two-phase flow in the pipeline. For example, if Figure 2 As shown, assuming that the transducer array includes N t The transducers are arranged in a ring, and the transducer serving as the ultrasonic emission point is T x , the transducer as the ultrasonic receiving point is R y , then the value range of x and y is 1 to N t It should be noted that, usually, x is not equal to y. If x is equal to y, it means that the transducer used as the ultrasound emission point and the transducer used as the ultrasound reception point are the same transducer. Since the transducer itself cannot receive the ultrasound signal emitted by itself, therefore, when x is equal to y, the ultrasound projection path T x -R y Ultrasonic signal value on Can be set to 0.

[0069] The grid image of the transducer array needs to cover the area of ​​the transducer array. The particle volume fraction in each grid in the grid image is a constant value, and the total sound attenuation of the sound wave emitted by the ultrasonic emission point on the propagation path is equal to the sum of the unit sound attenuation of the grid corresponding to the propagation path.

[0070] For example, when determining the grid image, square grid division can be performed according to the finite element principle, and the grid image can be determined as an image containing 32×32 to 128×128 square grids. Of course, those skilled in the art can also set the grid image to an image containing other numbers of square grids, and this embodiment does not limit this, as long as the grid image can cover the area range of the transducer array.

[0071] Step S130, respectively determining the sensitive intervals of each ultrasound projection path in the transducer array in the grid image.

[0072] Specifically, a weight value will be added to the sensitive interval in subsequent steps to indicate that different types of particles appear in the sensitive interval.

[0073] For example, Figure 2 As shown, the counterclockwise direction is taken as the positive direction, then the ultrasound projection path T x -Ry The sensitive interval in the grid image may include the midpoint T of the first ultrasound transmission interval x-0.5 , the midpoint of the second ultrasonic emission interval T x+0.5 and the ultrasonic receiving point R y The previous ultrasonic receiving point R y-1 , Ultrasonic receiving point R y The next ultrasonic receiving point R y+1 The trapezoidal area is composed of a first ultrasonic transmission interval midpoint T x-0.5 is the ultrasonic emission point T x The previous ultrasonic emission point T x-1 The midpoint of the interval of the second ultrasonic emission interval is T x+0.5 is the ultrasonic emission point T x The next ultrasonic emission point T x+1 The midpoint of the interval.

[0074] By placing the ultrasound projection path T x -R y The sensitive interval in the grid image is set as a trapezoidal area, which can make the sensitive interval more consistent with the characteristics of beam diffusion and acoustic wave propagation, and balance the weight value of the grid, which helps to improve the reconstruction accuracy of the morphology and field distribution image corresponding to the mixed particle two-phase flow.

[0075] Step S140: determining the weight value of each grid in each sensitive interval based on the ultrasound signal projection data.

[0076] Specifically, different ultrasonic signal values ​​on the ultrasonic projection path correspond to different grid weight values, so that the particle type corresponding to the grid is reflected through the grid weight value.

[0077] Exemplarily, when the ultrasonic signal value on each ultrasonic projection path in the mixed particle two-phase flow is expressed as Formula 1, step S140 may include: if the ultrasonic signal value The value is 0. , then the ultrasound projection path T x -R y The weight values ​​of all grids in the sensitive interval in the grid image are set to the first weight value. The value is Right now , then the ultrasound projection path T x -R y The weight value of each grid in the sensitive interval of the grid image is set to a second weight value determined by the linear back projection method. The value is 1. , then the ultrasound projection path T x -R yThe weight values ​​of all grids in the sensitive interval in the grid image are set to the third weight value. The first weight value is less than the third weight value, and the third weight value is less than or equal to the ultrasonic signal value. The value is is the minimum value among the second weight values ​​corresponding to each grid. That is to say, the first weight value is the minimum, the second weight value is the maximum, and the third weight value is between the first weight value and the second weight value. For example, the first weight value can be 0, and the third weight value can be 1. Of course, the first weight value and the third weight value can also be other values, as long as the first weight value is the minimum, the second weight value is the maximum, and the third weight value is between the first weight value and the second weight value.

[0078] Specifically, When the ultrasound projection path T x -R y There are large particles in the grid, so the first weight value is used to characterize the target in the corresponding grid as a large particle, so as to obtain the morphology and field distribution image of the large particle according to the first weight value. Compared with the second weight value and the third weight value, the first weight value is the smallest. Therefore, in the morphology and field distribution image corresponding to the mixed particle two-phase flow, the corresponding area of ​​the large particle will be obviously distinguished from the corresponding area of ​​the background phase and the small particle dispersion system.

[0079] When the ultrasound projection path T x -R y Only the background area is passed through, therefore, the third weight value is used to characterize the target in the corresponding grid as the background phase, so as to obtain the morphology and field distribution image of the background phase according to the third weight value.

[0080] When the ultrasound projection path T x -R y There are small particle dispersions but no large particles in the grid, therefore, the second weight value is used to characterize that the target in the corresponding grid is a small particle dispersion, so as to obtain the morphology and field distribution image of the small particle dispersion according to the second weight value.

[0081] Exemplarily, the second weight value determined by the linear back projection method includes: The second weight value is determined, wherein represents the sensitivity coefficient matrix, represents the ultrasonic signal value matrix, Represents a matrix composed of second weight values ​​corresponding to all grids in the grid image.

[0082] Specifically, When , the ultrasonic signal value between any pair of ultrasonic emission points and ultrasonic receiving points, that is, on any ultrasonic projection path, has a certain relationship with the distribution of the small particle dispersion system. Therefore, based on the known sensitivity coefficient matrix and the ultrasound signal value matrix , construct a matrix composed of the second weight value The linear equations , using the linear equations Solved , obtain the second weight value corresponding to each grid in the grid image. Among them, the ultrasound signal value matrix It is M×1 dimensional, where M represents the number of transducers in the transducer array. t The square of . Ultrasonic signal value matrix Each element in is from 1 to N t The ultrasonic emission points are respectively connected to the 1st to Nth t The ultrasonic signal value on the ultrasonic projection path between the ultrasonic receiving points. In other words, the ultrasonic signal value matrix The elements in are , the value range of x and y is 1 to N t The second weight matrix It is N×1 dimensional, where N represents the total number of grids included in the grid image. Each element in is the second weight value corresponding to each grid in the grid image. Sensitivity coefficient matrix is M×N dimensional. That is, the sensitivity coefficient matrix The dimension of is determined by the number of transducers in the transducer array and the number of grids in the grid image.

[0083] By using the linear equations Determining the second weight value can further improve the accuracy of the morphology and field distribution image corresponding to the mixed particle two-phase flow reconstructed based on the grid weight value.

[0084] Step S150, based on the weight value of each grid in the sensitive interval, the grid image is reconstructed to obtain the morphology and field distribution image corresponding to the mixed particle two-phase flow.

[0085] Specifically, step S150 can use the weight value of each grid as the pixel value corresponding to each grid, and use the image determined by each pixel value as the morphology and field distribution image corresponding to the mixed particle two-phase flow.

[0086] Exemplarily, step S150 includes: adding the weight values ​​of each grid in the sensitive interval corresponding to each ultrasound projection path according to their positions to obtain the weight accumulation value corresponding to each grid in the grid image; converting the weight accumulation value corresponding to each grid in the grid image into corresponding pixel values ​​to obtain a morphology and field distribution image.

[0087] Specifically, since different ultrasonic projection paths may overlap in sensitive intervals in the grid image, the corresponding overlapping area may include multiple grids. Therefore, in order to make the final weight value corresponding to each grid reflect the ultrasonic signal value on all ultrasonic projection paths, this embodiment accumulates the weight values ​​of the grids corresponding to the sensitive intervals of different ultrasonic projection paths to obtain the corresponding weight accumulation value, which is the final weight value corresponding to the grid. Then, the final weight value corresponding to each grid is used as its corresponding pixel value to obtain the morphology and field distribution image corresponding to the mixed particle two-phase flow.

[0088] Compared with the prior art, the method for synchronously reconstructing the morphology and field distribution of a mixed particle two-phase flow provided in the embodiments of the present invention acquires ultrasonic signal projection data of the mixed particle two-phase flow, and reconstructs the morphology and field distribution image corresponding to the mixed particle two-phase flow based on the ultrasonic signal projection data. This not only realizes the synchronous reconstruction of the morphology and field distribution of the large particle and small particle dispersion system in the mixed particle two-phase flow, but also effectively improves the reconstruction efficiency and detection efficiency of the morphology and field distribution image of the mixed particle two-phase flow, and has high practicality.

[0089] In order to enable those skilled in the art to better understand the above implementation, a specific example is provided below for illustration.

[0090] Combined Figure 3 , a method for synchronous reconstruction of the morphology and field distribution of mixed particle two-phase flow, including two parts, S100 and S200.

[0091] The S100 part is used to obtain the ultrasonic signal projection data of mixed particle two-phase flow. Specifically includes:

[0092] Step S101, calculating the acoustic reflection coefficient of sparse large particles in the mixed particle two-phase flow . Acoustic reflection coefficient of large particles The reflected sound pressure The incident wave sound pressure The ratio of is described as .in, represents the acoustic impedance of large particles, Represents the acoustic impedance of the background phase.

[0093] Step S102, obtaining the acoustic transmission coefficient of sparse large particles .in, .

[0094] Step S103, collecting and processing the ultrasonic signal amplitude of the pure background phase (without mixed particles).

[0095] Step S104, performing signal acquisition and preprocessing on the small particle dispersion system (excluding large particles), that is, performing ultrasonic signal acquisition and preprocessing on the mixed particle two-phase flow containing only the small particle dispersion system but not the large particles.

[0096] Step S105, collecting and processing signals of the large particle phase added to the small particle dispersion. That is, collecting and preprocessing ultrasonic signals of the mixed particle two-phase flow containing both the small particle dispersion and the large particles. The ultrasonic signal values ​​on each ultrasonic projection path are obtained, which are expressed as Formula 1:

[0097] Formula 1.

[0098] in, represents the ultrasound projection path T x -R y Only after the background phase, represents the ultrasound projection path T x -R y Through the small particle dispersion system, Indicates that the ultrasound projection path T x -R y There are large particles in it.

[0099] The S200 part is used to reconstruct the morphology and field distribution image corresponding to the mixed particle two-phase flow based on the ultrasonic signal projection data. Specifically includes:

[0100] Step S201, reconstructing image grid division, that is, determining the grid image of the transducer array corresponding to the ultrasound signal projection data.

[0101] Step S202, determining the sensitive interval, that is, respectively determining the sensitive interval of each ultrasound projection path in the transducer array in the grid image.

[0102] Step S203, based on the ultrasonic signal projection data, determine the weight value of each grid in each sensitive interval. Thus, the weight value of the reconstruction area of ​​the background phase, the weight of the field distribution of the small particle dispersion system, and the weight of the sparse large particle morphology are obtained respectively. When the ultrasound projection path T x -R y There are large particles in the ultrasonic projection path T x -R y The weight values ​​of all grids in the sensitive interval in the grid image are set to a first weight value, and the value of the first weight value is 0. When the ultrasound projection path T x -R y There are small particle dispersions but no large particles in the ultrasonic projection path T x -R y The weight values ​​of all grids in the sensitive interval of the grid image are set to the second weight value, and the second weight values ​​corresponding to each grid are respectively the matrix The corresponding elements in the matrix The corresponding elements in the linear equations Solve to get, represents the sensitivity coefficient matrix, represents the ultrasound signal value matrix. When the ultrasound projection path T x -R y Only passing through the background area, the ultrasound projection path T x -R y The weight values ​​of all grids in the sensitive interval in the grid image are set to a third weight value, and the value of the third weight value is 1.

[0103] After the weight value of each grid in each sensitive interval is obtained, the weight values ​​of each grid in the sensitive interval corresponding to each ultrasound projection path are added according to their positions to obtain the weight accumulation value corresponding to each grid in the grid image; the weight accumulation value corresponding to each grid in the grid image is converted into the corresponding pixel value to obtain the morphology and field distribution image.

[0104] Using a transducer array consisting of 16 transducers, Figure 3 The method for synchronous reconstruction of the morphology and field distribution of the mixed particle two-phase flow shown in FIG. reconstructs the morphology and field distribution image corresponding to the mixed particle two-phase flow in a pipe with a diameter of 60 mm. When the background phase in the mixed particle two-phase flow is water, the small particle dispersion system is a polystyrene particle suspension, and the large particles are bubbles, the morphology and field distribution image corresponding to the mixed particle two-phase flow is as follows: Figure 4 As shown in the figure. The green area indicates the area where the background phase, i.e. the continuous phase medium water, is located. There are no particles in this area. The blue area indicates the area where the large particles are located, and its weight value in the image is the lowest. The red-orange gradient area indicates the area where the small particle dispersion system is located, reflecting the concentration field information of the small particle dispersion system.

[0105] Another embodiment of the present disclosure relates to a system for synchronously reconstructing the morphology and field distribution of a mixed particle two-phase flow, such as Figure 5 As shown, it includes an acquisition module 510 , a first determination module 520 , a second determination module 530 , a third determination module 540 , and a reconstruction module 550 .

[0106] The acquisition module 510 is used to acquire ultrasonic signal projection data of mixed particle two-phase flow.

[0107] The first determination module 520 is used to determine a grid image of the transducer array corresponding to the ultrasound signal projection data.

[0108] The second determination module 530 is used to respectively determine the sensitive intervals of each ultrasound projection path in the transducer array in the grid image.

[0109] The third determination module 540 is used to determine the weight value of each grid in each sensitive interval based on the ultrasound signal projection data.

[0110] The reconstruction module 550 is used to reconstruct the grid image based on the weight value of each grid in the sensitive interval to obtain the morphology and field distribution image corresponding to the mixed particle two-phase flow.

[0111] The specific implementation method of the system for synchronously reconstructing the morphology and field distribution of the mixed particle two-phase flow provided in the embodiment of the present disclosure can be found in the method for synchronously reconstructing the morphology and field distribution of the mixed particle two-phase flow provided in the embodiment of the present disclosure, and will not be repeated here.

[0112] The system for synchronously reconstructing the morphology and field distribution of a mixed particle two-phase flow provided in the embodiments of the present disclosure can be applied to a flow test pipe section containing a mixed particle two-phase flow.

[0113] like Figure 6 As shown, the background phase in the flow test pipe section 100 containing the mixed particle two-phase flow can be a medium water 130, the small particle dispersion system 140 can be a polystyrene particle suspension, and the large particle 150 can be an air bubble. The transducers 120 in the transducer array 110 are arranged in a ring outside the pipe of the flow test pipe section 100, wherein the transducer 120 can be an ultrasonic sensor. When the diameter of the flow test pipe section 100 is 60 mm, the number of transducers 120 in the transducer array 110 can take any integer value from 16 to 32, so as to obtain the ultrasonic signal projection data of the mixed particle two-phase flow in the flow test pipe section 100 through these transducers 120, so as to characterize the mixed flow distribution after the small particle dispersion system in the vertical pipe column is disturbed by the large particles based on the ultrasonic signal projection data.

[0114] The ultrasonic signal projection data of the mixed particle two-phase flow in the flow test pipe section 100 can be obtained by the ultrasonic detection node 200 based on the transducer array 110. Among them, the ultrasonic detection node 200 can be provided with an ultrasonic receiving / transmitting driving module 210, a mixed particle two-phase flow signal acquisition and storage module 220, a data transmission interface 230, and a mixed particle two-phase flow signal processing module 240.

[0115] When obtaining the ultrasonic signal projection data of the mixed particle two-phase flow, the ultrasonic beam angle emitted by the transducer 120 in the transducer array 110 needs to just cover the tested pipe section area in the flow test pipeline 100, and can form a super-attenuation signal at the transducer as the ultrasonic receiving point. The ultrasonic receiving / transmitting driving module 210 in the ultrasonic detection node 200 receives the super-attenuation signal at the transducer as the ultrasonic receiving point, that is, the weak signal after the mixed particle two-phase flow is attenuated, and sends the super-attenuation signal as the ultrasonic signal of the mixed particle two-phase flow to the mixed particle two-phase flow signal acquisition and storage module 220. Afterwards, according to actual needs, the mixed particle two-phase flow signal acquisition and storage module 220 sends the ultrasonic signal of the mixed particle two-phase flow to the mixed particle two-phase flow signal processing module 240 through the data transmission interface 230. The mixed particle two-phase flow signal processing module 240 processes the ultrasonic signal of the mixed particle two-phase flow to obtain the ultrasonic signal projection data of the mixed particle two-phase flow. At the same time, the ultrasonic transceiver / transmitter driving module 210 can also provide reference clocks and synchronization signals for each module in the ultrasonic detection node 200 and coordinate the system working timing.

[0116] The mixed particle two-phase flow morphology and field distribution synchronous reconstruction system provided in the embodiment of the present disclosure can be used as a mixed particle two-phase flow synchronous reconstruction and display unit 300, which is used to reconstruct the morphology and field distribution image corresponding to the mixed particle two-phase flow based on the ultrasonic signal projection data of the mixed particle two-phase flow, and display the obtained morphology and field distribution image. For example, when the diameter of the flow test pipe section 100 is 60 mm and the transducer array 110 includes 16 transducers, the reconstructed morphology and field distribution image corresponding to the mixed particle two-phase flow is as follows: Figure 4 shown.

[0117] Compared with the prior art, the system for synchronous reconstruction of the morphology and field distribution of mixed particle two-phase flow provided by the embodiments of the present disclosure not only realizes the synchronous reconstruction of the morphology and field distribution of large particle and small particle dispersion systems in the mixed particle two-phase flow, but also effectively improves the efficiency of morphology and field distribution image reconstruction and detection efficiency of the mixed particle two-phase flow, and has high practicality.

[0118] Another embodiment of the present disclosure relates to an electronic device, such as Figure 7 As shown, including:

[0119] at least one processor 701; and,

[0120] A memory 702 is communicatively connected to at least one processor 701; wherein,

[0121] The memory 702 stores instructions that can be executed by at least one processor 701, and the instructions are executed by at least one processor 701 so that the at least one processor 701 can execute the method for synchronously reconstructing the morphology and field distribution of the mixed particle two-phase flow described in the above embodiment.

[0122] Among them, the memory and the processor are connected in a bus manner, and the bus may include any number of interconnected buses and bridges, and the bus connects various circuits of one or more processors and memories together. The bus can also connect various other circuits such as peripherals, voltage regulators, and power management circuits, which are well known in the art and are therefore not further described herein. The bus interface provides an interface between the bus and the transceiver. The transceiver can be one element or multiple elements, such as multiple receivers and transmitters, providing a unit for communicating with various other devices on a transmission medium. The data processed by the processor is transmitted on a wireless medium via an antenna, and further, the antenna also receives data and transmits the data to the processor.

[0123] The processor is responsible for managing the bus and general processing, and can also provide various functions, including timing, peripheral interfaces, voltage regulation, power management, and other control functions. Memory can be used to store data used by the processor when performing operations.

[0124] Those skilled in the art will appreciate that the above-mentioned embodiments are specific embodiments for implementing the present disclosure, and in actual applications, various changes may be made thereto in form and detail without departing from the spirit and scope of the present disclosure.

Claims

1. A method for synchronously reconstructing the morphology and field distribution of a mixed particle two-phase flow, characterized in that: The synchronous reconstruction method comprises: Acquire ultrasonic signal projection data of mixed particle two-phase flow; Determining a grid image of a transducer array corresponding to the ultrasound signal projection data; respectively determining sensitive intervals of each ultrasound projection path in the transducer array in the grid image; Determining a weight value of each grid in each sensitive interval based on the ultrasound signal projection data; Based on the weight value of each grid in the sensitive interval, the grid image is reconstructed to obtain the morphology and field distribution image corresponding to the mixed particle two-phase flow; The method of obtaining ultrasonic signal projection data of mixed particle two-phase flow includes: collecting and processing the ultrasonic signal amplitude of the background phase in the mixed particle two-phase flow; Based on the ultrasonic signal amplitude of the background phase, ultrasonic signal acquisition and preprocessing are performed on the mixed particles in the mixed particle two-phase flow to obtain ultrasonic signal values ​​on each of the ultrasonic projection paths; In the mixed particle two-phase flow, the ultrasonic signal value on each ultrasonic projection path is expressed as Formula 1: Formula 1; in, represents the ultrasound projection path T x -R y The ultrasonic signal value on represents the ultrasound projection path T x -R y The ultrasonic signal amplitude of the upper background phase, represents the ultrasound projection path T x -R y The amplitude of the ultrasonic transmission attenuation signal in the small particle dispersion system is represents the sound transmission coefficient, T x represents the ultrasonic emission point with serial number x, R y Indicates the ultrasonic receiving point with serial number y; Acoustic Transmission Coefficient Expressed as formula 2: Formula 2: in, represents the ultrasonic incident angle, represents the ultrasonic refraction angle, represents the acoustic impedance of large particles, represents the acoustic impedance of the background phase; The step of determining the weight value of each grid in each sensitive interval based on the ultrasound signal projection data includes: If the ultrasonic signal value If the value is 0, the ultrasound projection path T x -R y The weight values ​​of all grids in the sensitive interval in the grid image are set to a first weight value; If the ultrasonic signal value The value is , then the ultrasound projection path T x -R y The weight value of each grid in the sensitive interval in the grid image is set to a second weight value determined by a linear back-projection method; If the ultrasonic signal value If the value is 1, the ultrasound projection path T x -R y The weight values ​​of all grids in the sensitive interval in the grid image are set to a third weight value; The first weight value is less than the third weight value, and the third weight value is less than or equal to the ultrasonic signal value. The value is The minimum value of the second weight values ​​corresponding to each grid; The second weight value determined by the linear back projection method includes the following steps: The second weight value is determined, wherein represents the sensitivity coefficient matrix, represents the ultrasonic signal value matrix, A matrix representing the second weight values ​​corresponding to all grids in the grid image; Ultrasound projection path T x -R y The sensitive interval in the grid image includes the midpoint T of the first ultrasound transmission interval x-0.5 , the midpoint of the second ultrasonic emission interval T x+0.5 and the ultrasonic receiving point R y The previous ultrasonic receiving point R y-1 , Ultrasonic receiving point R y The next ultrasonic receiving point R y+1 The trapezoidal area is composed of a first ultrasonic transmission interval midpoint T x-0.5 is the ultrasonic emission point T x The previous ultrasonic emission point T x-1 The midpoint of the interval of the second ultrasonic emission interval is T x+0.5 is the ultrasonic emission point T x The next ultrasonic emission point T x+1 The midpoint of the interval.

2. The synchronous reconstruction method according to claim 1, characterized in that: The grid image is reconstructed based on the weight value of each grid in the sensitive interval to obtain the morphology and field distribution image corresponding to the mixed particle two-phase flow, including: The weight values ​​of each grid in the sensitive interval corresponding to each of the ultrasound projection paths are added up according to their positions to obtain the weight accumulation value corresponding to each grid in the grid image; The weight accumulation values ​​corresponding to each grid in the grid image are converted into corresponding pixel values ​​to obtain the morphology and field distribution image.

3. A system for synchronous reconstruction of morphology and field distribution of mixed particle two-phase flow, characterized in that: The synchronous reconstruction system comprises: An acquisition module, used for acquiring ultrasonic signal projection data of mixed particle two-phase flow; A first determination module, configured to determine a grid image of a transducer array corresponding to the ultrasound signal projection data; A second determination module is used to respectively determine the sensitive intervals of each ultrasound projection path in the transducer array in the grid image; A third determination module, configured to determine a weight value of each grid in each sensitive interval based on the ultrasound signal projection data; A reconstruction module, used to reconstruct the grid image based on the weight value of each grid in the sensitive interval to obtain the morphology and field distribution image corresponding to the mixed particle two-phase flow; The method of obtaining ultrasonic signal projection data of mixed particle two-phase flow includes: collecting and processing the ultrasonic signal amplitude of the background phase in the mixed particle two-phase flow; Based on the ultrasonic signal amplitude of the background phase, ultrasonic signal acquisition and preprocessing are performed on the mixed particles in the mixed particle two-phase flow to obtain ultrasonic signal values ​​on each of the ultrasonic projection paths; In the mixed particle two-phase flow, the ultrasonic signal value on each ultrasonic projection path is expressed as Formula 1: Formula 1; in, represents the ultrasound projection path T x -R y The ultrasonic signal value on represents the ultrasound projection path T x -R y The ultrasonic signal amplitude of the upper background phase, represents the ultrasound projection path T x -R y The amplitude of the ultrasonic transmission attenuation signal in the small particle dispersion system is represents the sound transmission coefficient, T x represents the ultrasonic emission point with serial number x, R y Indicates the ultrasonic receiving point with serial number y; Acoustic Transmission Coefficient Expressed as formula 2: Formula 2: in, represents the ultrasonic incident angle, represents the ultrasonic refraction angle, represents the acoustic impedance of large particles, represents the acoustic impedance of the background phase; The step of determining the weight value of each grid in each sensitive interval based on the ultrasound signal projection data includes: If the ultrasonic signal value If the value is 0, the ultrasound projection path T x -R y The weight values ​​of all grids in the sensitive interval in the grid image are set to a first weight value; If the ultrasonic signal value The value is , then the ultrasound projection path T x -R y The weight value of each grid in the sensitive interval in the grid image is set to a second weight value determined by a linear back-projection method; If the ultrasonic signal value If the value is 1, the ultrasound projection path T x -R y The weight values ​​of all grids in the sensitive interval in the grid image are set to a third weight value; The first weight value is less than the third weight value, and the third weight value is less than or equal to the ultrasonic signal value. The value is The minimum value of the second weight values ​​corresponding to each grid; The second weight value determined by the linear back projection method includes the following steps: The second weight value is determined, wherein represents the sensitivity coefficient matrix, represents the ultrasonic signal value matrix, A matrix representing the second weight values ​​corresponding to all grids in the grid image; Ultrasound projection path T x -R y The sensitive interval in the grid image includes the midpoint T of the first ultrasound transmission interval x-0.5 , the midpoint of the second ultrasonic emission interval T x+0.5 and the ultrasonic receiving point R y The previous ultrasonic receiving point R y-1 , Ultrasonic receiving point R y The next ultrasonic receiving point R y+1 The trapezoidal area is composed of a first ultrasonic transmission interval midpoint T x-0.5 is the ultrasonic emission point T x The previous ultrasonic emission point T x-1 The midpoint of the interval of the second ultrasonic emission interval is T x+0.5 is the ultrasonic emission point T x The next ultrasonic emission point T x+1 The midpoint of the interval.

4. An electronic device, characterized in that: include: at least one processor; as well as, a memory communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the method for synchronously reconstructing the morphology and field distribution of the mixed particle two-phase flow described in claim 1 or 2.

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