Mine acoustic emission source high-precision positioning method based on finite element method

Abstract

The invention provides a mine acoustic emission source high-precision positioning method based on a finite element method. The method comprises the following steps: step 1, point source elastic wave propagation simulation based on the finite element method: step 101, constructing a three-dimensional space layered structure model; step 102, constructing a point sound source excitation model; step 103, setting a boundary condition and a low-reflection virtual domain; step 104, grid division; step 105, finite element simulation of point source elastic wave propagation; step 2, time difference inversion positioning: step 201, a probe arrangement strategy; step 202, waveform analysis and time difference information calculation; and step 203, carrying out inversion calculation on the sound source position. According to the method, the propagation process of sound waves in a three-dimensional layered space is simulated through a finite element method, advanced probe arrangement and an optimized positioning algorithm are combined, the problems that a traditional time difference positioning method is high in probe arrangement requirement and complex in calculation are solved, higher positioning precision and real-time performance are achieved, and the method is suitable for popularization and application. And the technical requirements of mine safety monitoring, water inrush early warning and rockburst prediction are met.

Description

Technical Field

[0001] The invention belongs to the technical field of mine safety monitoring, relates to acoustic emission monitoring, and specifically to a high-precision positioning method for mine acoustic emission sources based on a finite element method. Background Art

[0002] As an advanced non-destructive testing method, mine acoustic emission monitoring technology can evaluate the stability of rock structure by capturing low-frequency vibration signals generated by the rock formation during deformation and destruction. The low-frequency acoustic emission generated in mines is often called microseismic activity because its mechanism and its application in rock damage monitoring are very similar to microseismic activity. Acoustic emission monitoring technology has been widely used in mine production, especially in the prevention and control of coal mine water inrush, rock burst prediction and overall mine safety monitoring, showing important application value.

[0003] Sound source positioning technology is the core technology of the mine acoustic emission monitoring and early warning system, which can accurately monitor and determine the location of energy release inside the mine. Through sound source positioning, the specific location of rock deformation and damage can be identified in time, helping mine managers to warn and prevent possible dangerous events, thereby improving the safety and reliability of mine production.

[0004] Among the existing acoustic emission source positioning technologies, the time difference positioning method is one of the most widely used methods. Its basic principle is to calculate the location of the sound source based on the time difference when the signal of the acoustic emission source reaches the probes at different positions. The time difference positioning method specifically includes USBM acoustic emission source positioning method, Geiger method, Powell method, particle swarm algorithm and simplex positioning algorithm. Among them, the Geiger positioning method, as a classic time difference positioning method, has been widely used and improved. For example, Huang Xiaohong proposed a method combining the full-phase principle with Geiger positioning to improve the accuracy of rock acoustic emission source positioning and reduce the number of iterations; Lin Feng combined the linear positioning method with the Geiger method to avoid the problem of low positioning accuracy caused by improper selection of initial values; Zhao Yongsheng combined the angle method with the time difference method to develop a new probe method for locating acoustic emission sources; Hua Gangyun et al. proposed a constrained least squares (CLS) algorithm using arrival time difference (TDOA) and frequency difference (FDOA) to estimate the position and velocity of moving sound sources; Li Nan proposed the concept of error space for acoustic emission source positioning by using L1 norm statistics to perform residual analysis on acoustic emission source positioning.

[0005] Although the time difference positioning method has high positioning accuracy, its algorithm is complex and the space requirements for probe layout are high, which limits its rapid calculation in practical engineering applications. Especially under the complex geological conditions of mines, how to ensure the effectiveness of probe layout and the accuracy of data acquisition is still an important challenge. Therefore, it is urgent to develop a technology that is suitable for inversion positioning of mine acoustic emission sources in terms of probe layout and calculation method, so as to improve calculation efficiency and reduce the complexity of field applications. Summary of the invention

[0006] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a high-precision positioning method for mine acoustic emission sources based on the finite element method, so as to solve the technical problem that the accuracy and real-time performance of the acoustic emission source positioning method in the prior art need to be further improved in complex three-dimensional geological environments.

[0007] In order to solve the above technical problems, the present invention adopts the following technical solutions to achieve the above problems:

[0008] A high-precision positioning method for mine acoustic emission sources based on finite element method, the method comprising the following steps:

[0009] Step 1: Simulation of point source elastic wave propagation based on finite element method:

[0010] Step 101, constructing a three-dimensional layered structure model.

[0011] Step 102, construction of a point sound source excitation model:

[0012] Step 10201, setting of point sound source excitation.

[0013] Step 10202, spatial distribution function of point sound source.

[0014] Step 10203, time control function of point sound source.

[0015] Step 10204, construct a point sound source excitation model.

[0016] Step 103: setting boundary conditions and low-reflection virtual domain.

[0017] Step 104: grid division.

[0018] Step 105, finite element simulation of point source elastic wave propagation.

[0019] Step 2: Time difference inversion positioning:

[0020] Step 201, probe deployment strategy.

[0021] Step 202: waveform analysis and time difference information calculation.

[0022] Step 203: Inverse calculation of the sound source position.

[0023] Compared with the prior art, the present invention has the following technical effects:

[0024] (I) The method of the present invention is applicable to complex three-dimensional stratum environments, and solves the problem of large acoustic emission source positioning errors and poor real-time performance caused by the complexity of the geological environment in mines. The present invention simulates the propagation process of sound waves in three-dimensional layered space through the finite element method, and combines advanced probe layout and optimized positioning algorithm to overcome the problems of high probe layout requirements and complex calculations in traditional time difference positioning methods, achieving higher positioning accuracy and real-time performance, and meeting the technical requirements of mine safety monitoring, water inrush warning and rock burst prediction.

[0025] (II) The accuracy of the method of the present invention is improved: The refraction inversion method significantly improves the positioning accuracy by accurately modeling the propagation of sound waves between layers of materials. Compared with the traditional uniform velocity inversion method, the refraction inversion method of the present invention reduces the positioning error to within 2.3 meters, improves the positioning accuracy by about 14.5%, and reduces the relative error to 2.1%.

[0026] (III) The method of the present invention has wide applicability: the present invention is applicable to mines with complex geological conditions, especially to mines with obvious layered structures. By improving the positioning accuracy and real-time performance of acoustic emission monitoring, it provides important technical support for coal mine water inrush warning, rock burst prediction and overall safety management, and has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 Schematic diagram of the three-dimensional layered structure model.

[0028] Figure 2(a) is a graph of the time domain control function of a point sound source.

[0029] Figure 2(b) is the frequency spectrum distribution diagram of the point sound source excitation frequency (converted to 0.02).

[0030] Figure 3 It is the distribution diagram of the spatial function of point sound source excitation.

[0031] Figure 4(a) is the displacement array diagram when the sound source is located at (120, 80, 80) at the time point 0.02s.

[0032] Figure 4(b) is the surface displacement array at 0.062s.

[0033] FIG4( c ) is a slice diagram of the xz plane displacement array when y=50.

[0034] Figure 5 Schematic diagram of refraction inversion of acoustic emission sources in three-dimensional layered structures.

[0035] Figure 6Displacement diagram of different probe monitoring points.

[0036] Figure 7 This is a comparison chart of the results of the average velocity inversion algorithm and the refraction inversion algorithm for three-dimensional layered structures.

[0037] The specific contents of the present invention are further explained in detail below in conjunction with embodiments. DETAILED DESCRIPTION

[0038] It should be noted that, unless otherwise specified, all algorithms in the present invention adopt algorithms known in the prior art.

[0039] Specific embodiments of the present invention are given below. It should be noted that the present invention is not limited to the following specific embodiments, and all equivalent changes made on the basis of the technical solution of this application fall within the protection scope of the present invention.

[0040] Example:

[0041] This embodiment provides a method for high-precision positioning of mine acoustic emission sources based on the finite element method. The method comprises the following steps:

[0042] Step 1: Simulation of point source elastic wave propagation based on finite element method:

[0043] The point source elastic wave propagation simulation of the present invention can simulate the elastic wave propagation process of the acoustic emission source in a complex geological environment, thereby providing a basis for the subsequent high-precision positioning of the acoustic emission source.

[0044] Step 1 specifically includes the following steps:

[0045] Step 101, construction of a three-dimensional layered structure model:

[0046] As attached Figure 1 As shown, a three-dimensional layered structure model with a length of 200m, a width of 100m and a height of 100m is established.

[0047] In this embodiment, the three-dimensional space layered structure model is divided into three-layer structures, and the heights of the material interface in the Z direction are 30m and 70m respectively, so as to ensure the actual simulation effect of the three-dimensional space layered structure model.

[0048] Step 102, construction of a point sound source excitation model:

[0049] The point sound source control model in this embodiment can realistically simulate the propagation process of the acoustic emission source in the layered structure of a mine by comprehensively considering the excitation characteristics of the space function and the time function.

[0050] Step 10201, setting of point sound source excitation:

[0051] The sound source information provides excitation through surface space function and time function. A unit area load is applied in the normal direction of the plane as the initial excitation. The excitation intensity is set to 4.6 MPa with reference to the tensile damage strength of sandstone. The central frequency of the excitation is set to 100 Hz. The elastic wavefront generated is circular and is a point acoustic emission source in three-dimensional space.

[0052] In this step, the excitation of the point sound source reflects the local stress concentration and release caused by the deformation of rock under actual mine geological conditions.

[0053] Step 10202, spatial distribution function of point sound source:

[0054] The spatial distribution function of a point sound source is expressed by formula I.

[0055]

[0056] Where:

[0057] Gspace(x,y,z) represents the spatial distribution function of the point sound source;

[0058] A represents the excitation peak factor;

[0059] ds represents the surface area element excited by the power source;

[0060] dV represents the spatial volume element excited by the point sound source;

[0061] (x0, y0, z0) represents the coordinates of the point sound source;

[0062] (x, y, z) represents the coordinates of the point in space excited by the point sound source.

[0063] In this embodiment, it is preferred that (x0, y0, z0) is (120, 80, 80).

[0064] In this step, the control equation is used to simulate the variation of the excitation intensity of a point sound source in a three-dimensional layered structure model.

[0065] Step 10203, time control function of point sound source:

[0066] The time control function of the point sound source is the Ricker wavelet expression, which is shown in Formula II:

[0067]

[0068] Where:

[0069] Gtime(t) represents the time control function of the point sound source, describing the time characteristics of the waveform;

[0070] t represents the time variable, which is used to represent the propagation time of the wave;

[0071] t0 represents the delay time, which is 0.06s;

[0072] d represents the modulation factor, which is used to adjust the shape or decay rate of the waveform;

[0073] f0 represents the main frequency, which is 100Hz.

[0074] Specifically in this embodiment, the point sound source time domain control function of the point sound source excitation is shown in FIG. 2( a ), and the frequency spectrum distribution of the point sound source excitation frequency of the point sound source excitation is shown in FIG. 2( b ).

[0075] Step 10204, construct a point sound source excitation model:

[0076] In the three-dimensional layered structure model, the point sound source position is set as (x0, y 0， z0), in this embodiment, the value is (120, 80, 80). The excitation form of the point sound source is represented by the product of the surface space function and the time function, that is, the excitation form of the point sound source is as shown in Figure III.

[0077] G(x,y,z,t)=G space (x,y,z)·Gtime(t) Formula III.

[0078] Where:

[0079] G(x,y,z,t) represents the excitation form of the point sound source;

[0080] G space (x, y, z) represents the spatial distribution function of the point sound source;

[0081] Gtime(t) represents the time control function of the point sound source.

[0082] Specifically, in this embodiment, the spatial distribution of the point sound source excitation presents a spherical characteristic in three-dimensional space, as shown in the attached Figure 3 This excitation method can effectively simulate the local stress concentration caused by the change of ground stress in the mine.

[0083] Step 103, boundary conditions and low-reflection virtual domain settings:

[0084] As attached Figure 1 As shown in the figure, the model boundary of the three-dimensional layered structure model is set to a 10m thick low-reflection virtual domain to reduce the reflection effect of the boundary conditions on the propagation of sound waves.

[0085] In this step, in order to avoid the influence of elastic wave reflection at the boundary on the monitoring results, the present invention sets a "U"-shaped low-reflection virtual domain with a width of 10m in all directions of the three-dimensional layered structure model, thereby effectively reducing the boundary reflection phenomenon of the wave and ensuring that the propagation of sound waves in the layered geology is closer to the actual mine conditions.

[0086] Step 104, mesh division:

[0087] The grid of the three-dimensional layered structure model uses regular hexahedral units, and the grid is generated by automatic sweeping; the maximum grid unit size in the grid is controlled by the minimum wave velocity of the known material according to Formula IV, ensuring that the wave propagation process in the three-dimensional layered structure model can be accurately captured.

[0088]

[0089] Where:

[0090] L max Indicates the size of the largest grid cell;

[0091] Cs min Indicates the minimum wave velocity of shear waves;

[0092] f0 represents the main frequency, which is 100 Hz in this embodiment.

[0093] The partitioning strategy in this step ensures the calculation accuracy of the model while improving the stability and efficiency of the calculation.

[0094] The precise point sound source control model adopted in the present invention provides a reliable basis for the subsequent acoustic emission source inversion positioning, and provides theoretical support and practical basis for mine acoustic emission, microseismic monitoring and safety early warning.

[0095] Step 105, finite element simulation of point source elastic wave propagation:

[0096] Comsol software is used to simulate the propagation of point source elastic waves. The acoustic emission source in the three-dimensional layered structure is modeled by automatically sweeping the regular hexahedral units.

[0097] The maximum grid cell size in this step is controlled by the minimum wave velocity of the known material to ensure that the wave propagation in the formation is accurately captured. The model characterizes the propagation process of elastic waves through total vibration.

[0098] Specifically, in this embodiment, through the simulation process, the propagation path of elastic waves in the multilayer heterogeneous structure and the significant reflection and refraction phenomena caused by the difference in wave speed can be clearly observed, such as Figure 4(a) to Figure 4(c) As shown in Figure Figure 4(a) to Figure 4(c)It can be seen that at 0.02s, a spherical high-light point sound source is formed due to the point excitation; at 0.062s, the propagation of elastic waves in the three-layer space structure can be observed. In the slice diagram of the xz plane, it can be clearly seen that the elastic wave produces significant reflection and refraction at the material interface.

[0099] Step 2: Time difference inversion positioning:

[0100] In the present invention, the time difference inversion positioning method is one of the important algorithms used in the present invention to determine the precise position of the acoustic emission source in the three-dimensional layered structure. The method is based on the time difference of the acoustic wave signal from the sound source to each probe, combined with the complexity of the layered structure, to invert the spatial coordinates of the acoustic emission source.

[0101] The specific method of time difference inversion positioning includes the following steps:

[0102] Step 201, probe placement strategy:

[0103] The probes are arranged in a right-angled tetrahedron. When the entire probe cluster is located in the same material, the received elastic wave velocity is consistent. The relative position information between the probes is determined by the time difference information. The position of the point sound source can be determined by the intersection of two inversion lines in space, as shown in Formula V.

[0104]

[0105] Where:

[0106] (x s ,y s ,z s ) represents the coordinates of the sound source point S;

[0107] (x i ,y i ,z i ) represents the coordinates of the i-th probe, i=1,…,8;

[0108] δ xy It represents the angle between the projection of the propagation path from the acoustic emission source to the probe on the xy plane and the projection of other probes on the xy plane;

[0109] δ yz It represents the angle between the projection of the propagation path from the acoustic emission source to the probe on the yz plane and the projection of other probes on the yz plane;

[0110] β xy It represents the angle between the projection direction of the sound source to the probe propagation path on the xy plane and the reference axis (such as the x-axis);

[0111] β yzIt represents the angle between the projection direction of the sound source to the probe propagation path on the yz plane and the reference axis (such as the y-axis).

[0112] In this step, the probe is used to receive and record elastic wave information from a point sound source. Aiming at the complex geological characteristics of the three-dimensional layered structure, the probe is arranged in a right-angle tetrahedron to ensure effective coverage of all directions in the three-dimensional space and improve the accuracy of sound wave signal collection. By rationally arranging the probe, the problem of sound wave reflection and refraction caused by the layered structure in the mine environment can be effectively solved.

[0113] Specifically, in this embodiment, in a three-dimensional layered structure, the probes need to be arranged in a three-dimensional structure to adapt to the spatial complexity. Figure 5 As shown in the figure, the probes are arranged into a tetrahedron structure in the Cartesian coordinate system, in which three faces form a right triangle. Probe R4 is used as the origin of the coordinate system, and the other three probes are located on the three coordinate axes, and the distance from the origin (R4) is d. The coordinates of the acoustic emission source S are (x S ,y S , z S ). The coordinates of the probe Ri are (x i ,y i , z i ), where i = 1, 2, 3, 4. Another set of probes are arranged similarly with R8 as the origin.

[0114] The specific layout coordinates of the probe family in this embodiment are shown in Table 1.

[0115] Step 202, waveform analysis and time difference information calculation:

[0116] By analyzing the elastic wave waveform monitored by the probe, especially the arrival time of the crest of the first wave (longitudinal wave), the time difference of each probe receiving the acoustic emission source signal is determined; in this step, the time difference is the key input of positioning inversion and can effectively reflect the distance difference between the sound source and the probe.

[0117] In this embodiment, specifically, Figure 6 As shown, Figure 6 The waveforms obtained by the displacement monitoring of the above 8 probes are shown. By analyzing the arrival time of the first wave (longitudinal wave) peak, as shown in Table 1, the time difference information of the probe is calculated, which provides an important basis for the subsequent inversion calculation.

[0118] Table 1 Coordinates of tetrahedron probe layout and actual monitoring data of first wave arrival time

[0119]

[0120] Step 203, inverse calculation of the sound source position:

[0121] The average velocity inversion algorithm or refraction inversion algorithm is used to calculate the sound source position, and finally the location of the mine acoustic emission source is achieved.

[0122] In this step, the average velocity inversion algorithm assumes that the wave velocity of sound waves is consistent when propagating in the same medium, and directly uses the time difference information to calculate the position; while the refraction inversion algorithm takes into account the refraction effect of sound waves at the interface of the layered structure, and further optimizes the inversion accuracy by combining the material interface position and wave velocity difference.

[0123] In this embodiment, specifically, Figure 7 As shown, Figure 7 The results of refraction and average velocity inversion of the point sound source by the tetrahedron probe cluster are shown when the point sound source is located at the coordinates (120,80,80).

[0124] Specifically, in this embodiment, the error is calculated using Formula VI by comparing the distance between the predicted position and the actual position of the point sound source. By changing the position of the sound source point, we obtain the results and errors of different inversion methods, as shown in Table 2.

[0125]

[0126] Where:

[0127] ΔL represents the error;

[0128] (x s ,y s ,z s ) represents the actual coordinates of the sound source point S;

[0129] (x i ,y i ,z i ) represents the i-th predicted coordinates of the sound source point S.

[0130] Table 2 Results of average velocity and refraction point sound source inversion positioning of three-layer heterogeneous materials in space

[0131]

[0132] Inversion calculations show that when the influence of refraction at the interface of rock materials is ignored, there is a large error between the point sound source positioning result obtained using the traditional average velocity inversion method and the actual point source. However, if the inversion method is optimized and the influence of refraction caused by wave velocity differences is fully considered at the material boundary, the positioning accuracy will be significantly improved. By comparing multiple sets of data, the present invention found that using the average velocity inversion algorithm of the three-dimensional model, the overall error is controlled below 13.0 meters and the relative error is below 16.6%. When the refraction inversion algorithm is used, the overall error can be reduced to below 2.3 meters, and the relative error is also reduced to below 2.1%. This shows that compared with the traditional empirical average velocity algorithm, the refraction inversion algorithm can improve the positioning accuracy by about 14.5% in three-dimensional layered structures.

Claims

1. A high-precision positioning method for mine acoustic emission sources based on finite element method, characterized in that: The method comprises the following steps: Step 1: Simulation of point source elastic wave propagation based on finite element method: Step 101, constructing a three-dimensional layered structure model; Step 102, constructing a point sound source excitation model; Step 10201, setting of point sound source excitation; Step 10202, spatial distribution function of point sound source; Step 10203, time control function of point sound source; Step 10204, constructing a point sound source excitation model; Step 103, boundary conditions and low-reflection virtual domain settings; Step 104, grid division; Step 105, finite element simulation of point source elastic wave propagation; Step 2: Time difference inversion positioning: Step 201, probe placement strategy; Step 202, waveform analysis and time difference information calculation; Step 203: Inverse calculation of the sound source position.

2. The high-precision positioning method for mine acoustic emission sources based on the finite element method according to claim 1, characterized in that: The specific process of step 101 is: establish a three-dimensional space layered structure model with a length of 200m, a width of 100m, and a height of 100m.

3. The high-precision positioning method for mine acoustic emission sources based on the finite element method as claimed in claim 1, characterized in that: The specific process of step 102 is: Step 10201, setting of point sound source excitation: The sound source information provides excitation through surface space function and time function; a unit area load is applied in the plane normal direction as the initial excitation, and the excitation intensity is set to 4.6MPa; the central frequency of the excitation is set to 100Hz, and the elastic wavefront generated thereby is circular and is a point acoustic emission source in three-dimensional space; Step 10202, spatial distribution function of point sound source: The spatial distribution function of a point sound source is expressed by Equation Ⅰ; Where: Gspace(x,y,z) represents the spatial distribution function of the point sound source; A represents the excitation peak factor; ds represents the surface area element excited by the power source; dV represents the spatial volume element excited by the point sound source; (x0, y0, z0) represents the coordinates of the point sound source; (x, y, z) represents the coordinates of the point in space excited by the point sound source; Step 10203, time control function of point sound source: The time control function of the point sound source is the Ricker wavelet expression, which is shown in Formula II: Where: Gtime(t) represents the time control function of the point sound source, describing the time characteristics of the waveform; t represents the time variable, which is used to represent the propagation time of the wave; t0 represents the delay time; d represents the modulation factor, which is used to adjust the shape or decay rate of the waveform; f0 represents the main frequency; Step 10204, construct a point sound source excitation model: In the three-dimensional layered structure model, the point sound source position is set as (x0, y 0， z0), the excitation form of the point sound source is expressed by the product of the surface space function and the time function, that is, the excitation form of the point sound source is as shown in III; G(x, y, z, t) = G space (x, y, z) · Gtime(t), Equation III; Where: G(x,y,z,t) represents the excitation form of the point sound source; G space (x, y, z) represents the spatial distribution function of the point sound source; Gtime(t) represents the time control function of the point sound source.

4. The high-precision positioning method for mine acoustic emission sources based on the finite element method according to claim 1, characterized in that: The specific process of step 103 is: the model boundary of the three-dimensional layered structure model is set to a low-reflection virtual domain with a thickness of 10 m.

5. The high-precision positioning method for mine acoustic emission sources based on the finite element method as claimed in claim 1, characterized in that: The specific process of step 104 is as follows: the mesh of the three-dimensional layered structure model adopts regular hexahedron units, and the mesh is generated by automatic sweeping; the maximum mesh unit size in the mesh is controlled by the minimum wave velocity of the known material according to formula IV; Where: L max Indicates the size of the largest grid cell; Cs min Indicates the minimum wave velocity of shear waves; f0 represents the main frequency.

6. The high-precision positioning method for mine acoustic emission sources based on finite element method according to claim 1, characterized in that: The specific process of step 105 is: using Comsol software to simulate the propagation of point source elastic waves, and modeling the acoustic emission source in the three-dimensional layered structure through the regular hexahedral units generated by automatic sweeping.

7. The high-precision positioning method for mine acoustic emission sources based on finite element method according to claim 1, characterized in that: The specific process of step 201 is: the probes are arranged in a rectangular tetrahedron, the relative position information between the probes is determined by the time difference information, and the position of the point sound source can be determined by the intersection of two inversion lines in space, as shown in Formula V; Where: (x s ,y s ,z s ) represents the coordinates of the sound source point S; (x i ,y i ,z i ) represents the coordinates of the i-th probe, i=1,…,8; δ xy It represents the angle between the projection of the propagation path from the acoustic emission source to the probe on the xy plane and the projection of other probes on the xy plane; δ yz It represents the angle between the projection of the propagation path from the acoustic emission source to the probe on the yz plane and the projection of other probes on the yz plane; β xy It represents the angle between the projection direction of the sound source to the probe propagation path in the xy plane and the reference axis; β yz It represents the angle between the projection direction of the sound source to the probe propagation path on the yz plane and the reference axis.

8. The high-precision positioning method for mine acoustic emission sources based on finite element method according to claim 1, characterized in that: The specific process of step 202 is: by analyzing the arrival time of the peak of the elastic wave waveform monitored by the probe, the time difference of each probe receiving the acoustic emission source signal is determined.

9. The high-precision positioning method for mine acoustic emission sources based on finite element method according to claim 1, characterized in that: The specific process of step 203 is: using a mean velocity inversion algorithm or a refraction inversion algorithm to calculate the position of the sound source, and finally realizing the positioning of the mine acoustic emission source.

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