Topological derivative applied to cavity identification from elastodynamic surface measurements

This article is concerned with the use of topological derivative as a tool for preliminary elastic-wave probing of bounded or unbounded solids for buried objects. A formulation for computing the topological derivative field, based on an adjoint solution, is presented. A set of numerical results is included to illustrate the utility of topological derivative for outlining the cavity location and size prior to doing an actual inversion of measurements. The results presented here were obtained from a BIE solution, but the proposed methodology is applicable to other computational platforms such as the finite element method.