Research On Reflected Acoustic Ray Tracing And Its Tomography

Reflected acoustic tomography is more convenient in observing mode.It is a kind of non-destructive testing method,which has important research value and significance for observing condition and observing object without requirement.However,due to its limited observation mode,the uncertainty of the shape of the reflection interface,the coupling of the velocity and the reflection interface,the imaging results need to be improved,and it is necessary to further study.This paper aims to achieve independent inversion of reflection interface and velocity model by proposing a new objective function.Specific work is as follows:First of all,this paper describes the purpose and significance of the method of reflection acoustic ray tracing and its tomography,as well as the research history and development process of the subject at home and abroad.At the same time,the mathematical basis of tomography and the basic principle of ray tracing are introduced.This paper introduces the mathematical methods applied to the processing of reflection points and reflection interfaces and reflection interface are the least squares methods used in inversion imaging.Secondly,this paper establishes a model of reflected acoustic ray tracing,uses Hamiltonian to describe the ray trajectory,uses the target method for ray tracing.Reflected acoustic ray tracing is realized and applied to various media models,the angle of the reflected sound waves and the time information are obtained.Based on this,the inversion calculation of reflected acoustic tomography is carried out.Finally,this paper presents a new method to establish the objective function,and combines the least squares method to carry out the inversion calculation.By using the reflected acoustic ray angle inversion of the reflection interface,by using the reflected acoustic ray travel time inversion velocity model.To achieve separate inversion at the reflective interface and medium speed.Through the trial of the model,verify the feasibility of this method...