A factorization method for inverse elastic scattering in cavity structure
摘要
This paper is concerned with the inverse elastic scattering problem, which involves determining the shape and location of an interior elastic cavity from the near-field data using only two specific polarizations for two-dimensional case and three specific polarizations for three-dimensional case. Based on the scattered tensor, the crucial near-field operator in the framework of the factorization method is well-defined. We propose a theoretical factorization of the near-field operator and rigorously prove the properties of its associated operators involved in the factorization. Meanwhile, we discuss the uniqueness of the inverse scattering problem, in particular for the case of the disk cavity. Numerical experiments are carried out in two-dimensional and three-dimensional case to illustrate the feasibility and effectiveness of our algorithm. Based on the different characteristics of the indicator functions inside and outside the cavity, we give a well-performing method for obtaining a more accurate profile of the cavity using a truncated Fourier series as an approximation function.