32 results about "Acoustic wave equation" patented technology

The invention discloses a wind turbine blade internal damage diagnosis method based on a sound field graph neural network, and belongs to the technical field of wind turbine blade state detection, and the method comprises the steps: deploying a microphone array in a cabin, and collecting an acoustic signal when a blade rotates; constructing a space sound field graph structure by taking the microphone as a node and the sound wave propagation path as an edge; extracting nonlinear acoustic features by using a physical constraint graph neural network PC-GNN; generating a damage embedding vector based on self-supervised training contrast learning; and outputting a damage probability thermodynamic diagram and positioning information. According to the method, a directional microphone array is deployed in a cabin, and a sound wave propagation space diagram structure is constructed; designing a physical constraint graph neural network PC-GNN, and embedding an acoustic wave equation as a regularization item; the problem of scarcity of damaged samples is solved by adopting self-supervised contrast learning; and finally outputting a positioning thermodynamic diagram of the internal damage of the blade.

The invention relates to the technical field of precision measurement and instrument testing, in particular to a test error analysis method based on a high-precision acoustic phased array Doppler log, and aims to solve the problems that a traditional Doppler log mostly adopts a black box model driven by pure data, explicit modeling of a sound wave propagation and array receiving physical mechanism is lacked, and the test error analysis accuracy is poor. The problems that the generalization ability is weak under errors such as channel amplitude-phase mismatch and emission nonlinearity, real Doppler frequency shift is difficult to accurately extract, and the credibility of speed estimation cannot be quantified, so that output in a complex underwater environment is unreliable are solved. Physical priori such as an acoustic wave equation, a Doppler effect and array manifold is embedded into a neural network, physical consistent modeling and efficient reasoning of multi-channel echoes are achieved, an uncertainty quantification mechanism based on the evidence theory is further introduced, and the reliability and the likelihood of velocity estimation are dynamically evaluated, so that the reliability and the reliability of velocity estimation are improved. And the robustness and interpretability of the system in a complex underwater environment are effectively improved.

This invention provides a method, system, and storage medium for enhancing transformer fault acoustic signature diagnostic samples. The method includes: constructing the acoustic wave equation for the vibration of the core and windings propagating through the medium and the medium interface boundary conditions; performing sound field simulation on a fault model based on the acoustic wave equation and the medium interface boundary conditions to obtain a fault simulation sound field; determining a physical simulation dataset based on the fault simulation sound field; performing sparse representation on the physical simulation dataset to obtain a sparse dictionary and a sparse coefficient matrix; performing transfer learning on real fault samples to obtain a transfer dictionary; and performing sample enhancement based on the sparse dictionary, the sparse coefficient matrix, and the transfer dictionary to obtain enhanced transformer fault acoustic signature samples. In this embodiment, sample enhancement using the sparse dictionary, the sparse coefficient matrix, and the transfer dictionary effectively enhances the samples of transformer faults.

This invention discloses a method for measuring the sound power level of woodworking machine tool noise based on the sound intensity method, belonging to the field of machine tool noise measurement technology. Specifically, it includes: determining the housing surface covered by the projection of the tool's rotation plane as the main sound radiation area, and the main bearing seat mounting surface as the secondary sound radiation area; acquiring sound pressure, vibration acceleration signals, and dynamic air pressure signals in the main sound radiation area; resampling the dynamic air pressure signal in the rotational angular domain, extracting the reference air pulse waveform synchronized with the tool tooth sweep, and establishing an airflow-induced sound pressure model based on this and the phase relationship; calculating the surface normal vibration velocity based on the vibration acceleration, and establishing a structural radiation sound pressure model based on the sound wave equation; decomposing the sound pressure signal to obtain estimates of two types of components, and obtaining the net sound intensity of the main sound radiation area after parameter optimization; extracting the vibration frequency band energy of the secondary sound radiation area, calculating the equivalent sound intensity based on the sound radiation efficiency model, and spatially integrating to output the total sound power level. This invention provides an effective method for the accurate measurement and control of woodworking machine tool noise.

The invention discloses a seismic wave field simulation method and system in an attenuation medium. A new constant Q viscous sound wave equation is constructed to accurately meet the dispersion relation of the Kjartansson constant Q theory, and an amplitude attenuation item and a phase dispersion item are subjected to explicit separation, so that complete decoupling of attenuation and dispersion can be realized while the theoretically accurate constant Q dispersion relation is kept, and the frequency dispersion accuracy is improved. And solving a constant Q viscous acoustic wave equation through a generalized pseudo-spectral numerical simulation method based on space Fourier transform to obtain a seismic wave field with spatio-temporal variation, so that the precision of viscous acoustic wave simulation is remarkably improved.

The invention belongs to the technical field of geophysics, and discloses a random geologic model seismic wave efficient simulation method, system and device and a medium, and the method comprises the steps: obtaining a to-be-processed geologic model; constructing a two-dimensional first-order variable density acoustic wave equation corresponding to the geologic model through a Newton's law and a matter state equation; carrying out approximate processing on the two-dimensional first-order variable-density acoustic wave equation by utilizing a staggered grid finite difference analysis method based on a derivative multiplication rule; calculating a staggered grid finite difference operator based on a preset precision requirement; and discretizing the two-dimensional first-order variable-density acoustic wave equation by adopting a staggered grid finite difference operator, constructing a corresponding discrete format, and carrying out seismic wave forward modeling simulation. According to the technical scheme, the numerical simulation time can be shortened under the condition that the precision is not lost.

The invention discloses a meshless seismic wave forward modeling method based on a difference numerical method and related equipment, and belongs to the field of exploration geophysics. According to the method, flexible mesh generation is carried out based on an undulating surface seismic wave speed model, a surface interface is completely fitted, and a high-precision difference coefficient set is obtained without manually selecting deformation parameters; by adding a filter related to a second-order time item in a two-dimensional scalar time domain acoustic wave equation, the robustness and accuracy of numerical simulation are effectively improved, so that a high-precision and stable seismic wave numerical simulation result is obtained, the precision and stability of seismic data processing can be effectively improved by utilizing the method, and the seismic data processing efficiency is improved. The method provides solid technical support for loess tableland seismic wave forward modeling, and has important practical significance for evaluating the influence of the earth surface effect on exploration data in the loess tableland, improving the accuracy and reliability of the exploration data, analyzing the physical properties and change rules of underground media and simulating the physical properties and seismic wave propagation conditions of underground structures.

The invention discloses a seismic wave numerical simulation method based on k-space compensation and a related device, and belongs to the technical field of oil exploration. The method comprises the following steps: constructing a first-order fractional order Laplace viscous acoustic wave equation of a seismic wave field, and deducing a viscous acoustic wave equation only containing velocity field variables according to the first-order fractional order Laplace viscous acoustic wave equation; converting the viscous acoustic wave equation only containing the velocity field variable into a viscous acoustic wave equation only containing the displacement field variable; deducing a recursion formula of the displacement field according to the viscous acoustic wave equation only containing the displacement field variable, and further obtaining a k-space compensation-based wave field recursion formula according to the recursion formula of the displacement field; and obtaining seismic wave field parameters and underground medium parameters, and inputting the seismic wave field parameters and the underground medium parameters into a k-space compensation-based wave field recursion formula to obtain a seismic wave numerical simulation result. According to the method, the time accumulation error can be effectively suppressed, so that the method is suitable for a larger time step length; and excessive extra calculation amount is not introduced, so that the method is more efficient on the premise of ensuring the precision.

This invention discloses a method and apparatus for audio line status identification in communication equipment rooms. The method includes audio data acquisition, acoustic physical constraint modeling, multi-region acoustic feature importance classification, audio line status identification model design, constraint loss dynamic balance optimization, acoustic feature loss function construction, and audio line status identification. This invention belongs to the field of data processing technology, specifically referring to a method and apparatus for audio line status identification in communication equipment rooms. This scheme models the sound wave propagation in the equipment room based on a three-dimensional acoustic wave equation to suppress non-fault noise interference; it divides the equipment room into zones, quantitatively allocates the number of monitoring points and regional loss weights, focuses on core areas, and significantly improves the fault detection rate of critical lines; it introduces the measured background noise sound pressure level of the equipment room to construct a noise correction coefficient, significantly improving the robustness of fault identification; and it designs an exponential dynamic relaxation coefficient, combined with benchmark weight allocation, to further enhance the early fault detection capability in critical areas.

This application relates to the field of geological exploration technology and discloses a reverse-time migration method and electronic equipment. The reverse-time migration method includes: acquiring seismic exploration data in a viscoelastic medium; calculating a compensated backpropagation wavefield based on the inverse dispersion acoustic wave equation transformed to the frequency domain and the seismic exploration data; and obtaining a compensated reverse-time migration image based on the compensated forward propagation wavefield and the compensated backpropagation wavefield. By acquiring seismic exploration data in a viscoelastic medium, calculating a compensated backpropagation wavefield based on the inverse dispersion acoustic wave equation transformed to the frequency domain and the seismic exploration data, and obtaining a compensated reverse-time migration image based on the compensated forward propagation wavefield and the compensated backpropagation wavefield, this application can compensate for energy loss caused by absorption attenuation during the reverse-time migration process while suppressing high-frequency noise, ensuring the stability of the reverse-time migration results.

The application belongs to the technical field of petroleum geophysical exploration, and particularly relates to a moving medium seismic wave forward simulation method. The flowing property of seawater is introduced into an acoustic wave equation to construct a moving medium acoustic wave equation, and the equation can more accurately simulate the propagation of seismic waves in flowing seawater and stationary solid rock layers.

This disclosure relates to a method, apparatus, device, storage medium, and computer program for establishing a depth domain velocity model. The method includes: acquiring pre-stack seismic shot gather data for the current region; outputting velocity updates based on the pre-stack seismic shot gather data using a pre-trained initial depth domain velocity model; acquiring updated velocities based on the updated velocities; performing acoustic wave equation forward modeling on the updated velocities according to preset forward modeling parameters to obtain forward modeling records; establishing a L2-norm target loss function based on the forward modeling records and pre-acquired observation records; performing iterative inversion on the initial depth domain velocity model using the L2-norm target loss function; confirming the depth domain velocity model after reaching a preset number of iterations; and performing depth domain velocity analysis using the depth domain velocity model based on seismic data for the target region to obtain velocity data.

The invention belongs to the technical field of multiple wave imaging based on a one-way acoustic wave equation, and relates to a multiple wave joint migration inversion method aiming at a stratum attenuation effect, aiming at the attenuation effect existing in actual seismic exploration and combining the multiple wave imaging advantages of a joint migration inversion algorithm, the deep part energy and the resolution of a reflectivity migration ground are improved, and the stratum attenuation effect is improved. The shallow artifacts of the speed inversion result are eliminated, and the precision of the speed model is improved. The method comprises the following steps: picking up an initial velocity model and a reflectivity model through preprocessing according to obtained observation data; in each iteration, simulation data are obtained through full wave field simulation containing an attenuation effect, a wave field residual error is obtained by making a difference between the simulation data and observation data, and linear iteration updating is carried out on parameters through a gradient descent method; the reverse extrapolation of the wave field residual error can be mapped on the gradient of the propagation operator, and the gradient is converted into a velocity gradient through linear parameterization; in continuous iteration, the residual error between simulation data and observation data is minimized, and a satisfactory imaging result is obtained.

The application discloses a voice interaction method and system based on an intelligent doll, relates to the technical field of intelligent acoustic interaction, and comprises the following steps: performing time-frequency analysis and processing on a vibration feature matrix, combining with the density characteristics of human neck tissues, and generating a modal parameter set of vocal cord vibration through biomechanical modeling; inputting the modal parameter set of vocal cord vibration into a vibration-acoustic model to generate a sound source excitation field, compensating the sound source excitation field for environmental noise by using an acoustic feature matrix, and generating a time-domain pure speech signal through a sound wave equation; collecting real-time position coordinates of a user, calculating and driving a piezoelectric loudspeaker array of the intelligent doll to adjust a phase according to the spectral characteristics of the time-domain pure speech signal, forming a directional focused sound field, recording physiological feedback of the user, and generating a user physiological feedback matrix. The application solves a vocal cord displacement modal function vector by using a nonlinear integral and an augmented Lagrange algorithm, so that the collection accuracy and the noise resistance of a speech signal are improved at the source.

The invention discloses an attenuation-considered scattered wave reverse time imaging seismic positioning method and system for a complex structure, and the method comprises the steps: building a frequency domain viscous sound wave equation, and representing a stratum absorption attenuation effect through a complex velocity model; introducing a contrast source based on a scattering theory, and separating a background wave field from a scattering wave field; inverse time continuation considering attenuation compensation is carried out, and energy focusing is realized through reverse wave field propagation and filtering processing; determining a focus position by applying imaging conditions; the invention specifically relates to an earthquake event positioning method based on a scattering theory, in particular to an inverse time continuation earthquake source positioning method under the condition of considering stratum heterogeneity and energy attenuation compensation, which can be applied to micro-earthquake monitoring related to industrial activities, hydrofracture effect evaluation and earthquake event positioning in complex geological structures. The technical problems of a traditional earthquake positioning method in a complex structure and an attenuation medium are effectively solved, and a new technical support is provided for underground space fine detection and engineering safety monitoring.

The invention discloses a time migration method for a three-dimensional pre-stack wave equation in an imaging ray domain, which relates to the technical field of exploration geophysics and comprises the following steps of: deducing a bidirectional acoustic wave equation in an imaging ray coordinate system based on a Riemann wave field extrapolation theory in a three-dimensional semi-orthogonal coordinate system; an equation is directly solved by adopting a finite difference method, extrapolation of a seismic source and a receiving end wave field is achieved, and errors caused by Green function approximation in a traditional migration method are avoided; and generating a pre-stack time migration result by applying a zero-lag cross-correlation imaging condition. Through first-order linear disturbance approximation, an accurate three-dimensional time-depth conversion partial differential equation set is simplified into an optimized layer stripping algorithm, and a corresponding equation suitable for a weak transverse velocity change medium is deduced. According to the invention, the working process of three-dimensional wave equation time migration is realized in an imaging ray coordinate system, and an accurate seismic imaging result is generated; two-dimensional plane hypothesis limitation is avoided, and high-precision imaging technical guarantee is provided for seismic data processing of a complex structure area.

The application discloses a variable fractional order viscous acoustic wave equation attenuation compensation reverse time migration method and system, and the variable fractional order viscous acoustic wave equation attenuation compensation reverse time migration method comprises the following steps: a stable attenuation compensation viscous acoustic wave equation is constructed by introducing a regularization term; and based on the stable attenuation compensation viscous acoustic wave equation, a local cross-correlation imaging condition based on the Nyquist sampling theorem is used to carry out attenuation compensation reverse time migration of viscous acoustic waves. The application adopts the method of adding a regularization term, can effectively inhibit the exponential growth of high-frequency noise in seismic records in the compensation process, and ensures the numerical stability of the attenuation compensation process; the local cross-correlation imaging condition based on the Nyquist sampling theorem can effectively reduce the calculation and storage cost of Q compensation reverse time migration on the basis of adapting to complex structure imaging, and improve the practicability of the reverse time migration imaging of viscoelastic media.

This invention relates to the field of seismic data processing and interpretation, and discloses a method, apparatus, equipment, and storage medium for analyzing the elastic effects of seismic waves. The method includes: collecting well logging data from target wells exhibiting well-seismic mismatch in a target work area; acquiring stratigraphic data from the target wells; establishing P-wave velocity, S-wave velocity, and density models to obtain seismic wavelets; conducting forward modeling based on acoustic wave equations to obtain first seismic shot records; conducting forward modeling based on elastic wave equations to obtain second seismic shot records; migrating and imaging the first and second seismic shot records respectively to obtain acoustic seismic data and elastic wave seismic data; and determining whether the well-seismic mismatch is caused by seismic wave elastic effects by comparing and analyzing the amplitude and waveform variations of the acoustic and elastic wave seismic data with synthesized well logging data and field-acquired seismic data. This invention solves the problem of reasonably interpreting the causes of well-seismic mismatch.

The invention discloses a DAS data image generation method and device for underground structure visualization. Comprising the following steps: constructing a three-dimensional coordinate system, and obtaining an original sound wave equation, a strain rate parameter and a seismic source parameter of a vertical and transverse isotropic medium; simplifying the strain-displacement relational expression to obtain a conversion relation between the axial strain rate and the velocity component; speed components in the original acoustic wave equation are replaced based on the conversion relation, and an anisotropic acoustic wave equation suitable for DAS data is constructed; deducing a seismic source wave field extrapolation equation and a detection point wave field extrapolation equation according to the anisotropic acoustic wave equation; respectively inputting the focus parameter and the strain rate parameter into corresponding extrapolation equations to obtain a focus pressure wave field and a detection point pressure wave field; and performing mutual-closing imaging processing on the two types of pressure wave fields to obtain an initial result, and performing optimization processing to obtain an underground structure imaging result of the target DAS data. According to the invention, the precision and reliability of DAS data underground structure imaging under complex geological conditions are improved.

The invention belongs to the technical field of geophysical exploration seismic forward modeling, and discloses a method and a device for constructing and solving a viscous wave equation of an anisotropic medium, and the method comprises the steps: 1, constructing a pure acoustic wave equation in the anisotropic medium, and solving the pure acoustic wave equation of the anisotropic medium; step 2, based on a Kelvin-Voigt model, constructing a viscous acoustic wave equation in an isotropic medium; and combining the viscous acoustic wave equation in the isotropic medium with the pure acoustic wave equation in the anisotropic medium to obtain a viscous pure acoustic wave equation in the anisotropic medium. A numerical example shows that the obtained viscous pure acoustic wave equation in the anisotropic medium can effectively eliminate interference and generate high-precision P-wave response; meanwhile, the influence of the anisotropic attenuation medium on seismic wave kinematics and dynamics can be fully displayed, and an efficient and accurate wave field extrapolation tool is provided for subsequent anisotropic attenuation medium migration imaging and waveform inversion.

The present disclosure provides a method and device for determining the number of controlled source excitation combinations and the number of coverages, belonging to the field of energy development exploration. The determination method comprises: obtaining test data by performing multiple seismic exploration tests using a controlled source excitation combination arranged in the work area; determining a signal-to-noise ratio function of a seismic wave corresponding to the use of different numbers of controlled sources to excite the seismic wave in the seismic exploration test based on a velocity curve of the seismic wave, the test data, and a viscous acoustic wave equation of seismic wave propagation; and determining a target combination number and a target coverage number based on the signal-to-noise ratio function. The present disclosure can effectively improve the quality of seismic acquisition data while reducing the cost of seismic acquisition work.

The invention belongs to the technical field of geophysical exploration for petroleum, and particularly relates to a forward modeling method for moving medium seismic waves, which constructs a moving medium acoustic wave fluctuation equation by introducing seawater flow attributes into the acoustic wave fluctuation equation and can more accurately simulate the propagation of seismic waves in flowing seawater and static solid rock strata.

A method for modelling and migrating seismic data, that includes using an acoustic wave equation and a spatial distribution of one or more earth-model parameters. The acoustic wave equation is modified by including at least one secondary source term, and based on a seismic acquisition configuration, either calculating the seismic signals that would be detected from the modelled wavefield or migrating observed seismic signals or migrating residual signals as part of an inversion.

The invention provides a sound source positioning method and device, computer equipment and a storage medium. The method comprises the following steps: forming input data based on a space range corresponding to a target space and a prediction moment; inputting the input data into a pre-trained physical constraint neural network to obtain sound pressure information of the sound in the target space at the prediction moment; wherein the physical constraint neural network takes an acoustic wave equation as a physical equation, takes initial sound pressure distribution and change rate distribution of initial sound pressure as initial conditions, and takes an impedance boundary condition as a boundary condition; actual measurement data collected by a distributed acoustic sensing DAS system deployed in the target space is used as data constraint training; and based on the sound pressure information, determining position information of a target sound source emitting the sound in the target space.

The application discloses a VSP hourly velocity inversion method of a physical embedding recurrent neural network, applied to the field of seismic velocity inversion, and aims at the problem of low precision of existing seismic velocity inversion methods; on the basis of realizing the embedding of a recurrent neural network of a finite difference acoustic wave equation, the application modifies the back propagation algorithm of the RNN, calculates the residual error of a current wave field and a shot gather wave field at each independent time, takes the residual error as the loss at the current time, and sums the loss at the current time and the loss at the previous time at each time, so as to update the velocity model in the residual error updating range until the residual error meets the condition, and then the velocity inversion area is expanded, so that the step-by-step correction from the shallow part to the deep part is realized; compared with other inversion correction algorithms, the hourly inversion technology proposed by the application significantly improves the accuracy and reliability of the physical embedding RNN velocity inversion.

The application provides an anisotropic medium pure acoustic wave least square reverse time migration method, relates to the fields of data processing and oil and gas geophysical exploration, and comprises the following steps: calculating an anisotropic medium pure acoustic wave equation reverse migration operator; determining an anisotropic medium pure acoustic wave equation adjoint equation and a parameter perturbation gradient formula; solving the anisotropic medium pure acoustic wave equation reverse migration operator and the adjoint equation; determining an anisotropic medium pure acoustic wave equation Hessian matrix and vector product formula; calculating a model parameter perturbation gradient and a Gauss-Newton gradient precondition; and iteratively updating a velocity and an anisotropic parameter perturbation model. The Gauss-Newton Hessian operator gradient precondition suppresses crosstalk of different model parameter perturbations, establishes a velocity and an anisotropic parameter perturbation model, provides an efficient and accurate imaging analysis tool for seismic exploration and acquisition in a complex area, improves anisotropic medium seismic data migration imaging effect, and improves imaging precision and convergence speed of anisotropic medium pure acoustic wave least square reverse time migration.

The application discloses a kind of SBP-SAT-based block staggered grid seismic wave simulation method, belong to the technical field of seismic numerical simulation, first establish the first-order velocity-pressure acoustic wave equation containing auxiliary differential equation, then complete space domain staggered grid SBP discrete and SAT boundary correction term is injected into physical variable equation and PML auxiliary differential equation simultaneously, subsequently construct the non-uniform grid interface SAT coupling term that meets SBP energy compatible condition, finally complete seismic wave field simulation by parameter setting and time domain integration.The whole process eliminates the long-time numerical drift problem of PML under high-order format theoretically, realizes the energy conservation and stable coupling of coarse and fine grid interface, takes into account the double advantages of staggered grid low-frequency dispersion and block grid high efficiency, significantly improves the precision and computing performance of complex medium acoustic forward.

The application discloses a consequence simulation method based on hydrogen production by electrolysis of water, comprising constructing a multi-physical field coupling simulation model containing electric field, thermal field, flow field and stress field, and setting and calibrating geometric structure, physical property parameter, boundary condition and numerical strategy to obtain the base field distribution of the electrode system. The whole process model of bubble dynamics is introduced to simulate the nucleation, diffusion growth and detachment of bubbles, and the dynamic feedback of gas-liquid two-phase is realized by the volume fraction method, the bubble interface force and thermal expansion effect are coupled, the micro-crack formation of the electrode is judged by the stress criterion and crack initiation threshold, and the crack evolution is solidified by the virtual crack element or phase field method. The crack propagation process is simulated by combining the Miner criterion and Paris law, the acoustic source term is introduced and the acoustic wave equation is solved, and the whole-link prediction of electrode damage and hydrogen production performance is realized in the operation process of the water electrolysis hydrogen production system, and the effects of early warning, reliability evaluation and life optimization.

The invention discloses a numerical simulation method for seismic scalar waves of an onshore elastic medium. The method comprises the following specific steps: step 1, constructing a pseudo scalar wave equation in a first-order speed-stress-pseudo pressure form under an assumed condition of the elastic medium; 2, selecting the wave equation of the pseudo scalar wave in the step 1, and implementing seismic wave numerical simulation by adopting staggered grid finite difference; step 3, adding a PML boundary absorption condition, and eliminating artificial seismic wave reflection noise generated at a limited space boundary by seismic wave numerical simulation in the step 2; according to the method, wave field propagation characteristics of pseudo scalar waves in an elastic medium are successfully simulated, and wave field information comprises longitudinal wave information existing in conventional acoustic wave equation numerical simulation and also comprises a large amount of SP converted wave information; meanwhile, forward modeling parameters of seismic waves are successfully increased from a longitudinal wave speed and density two-parameter model to a longitudinal and transverse wave speed and density three-parameter model.