Application of a chaotic cavity transducer in inversal filter elastic detection and numercial simulation research

Addressing the problems of low quality focalization and low efficency of detection in traditional one channel time reversal Nondestructive Testing (NDT), a Chaotic Cavity Transducer (CCT) has been proposed and employed to improve focalization and detection. The CCT takes advantage of a medium's inherent ergodicity, solving the problems of "phantom" image and increased strain at the boundary of test media. For improved focalization, the Chirped Excitation (CE) source signal and Inverse Filter (IF) technique were used. CE leads to enhanced energy transfer into the test sample, while an IF uses more eigenmodes of reversal signal. In order to better understand the properties of CCT, numerical simulations were carried out using the nodal Discontinuous Galerkin Finite Element Method (DG-FEM). Results of numerical simulation of the CCT and the realization of image detection on reverberant raedium confirmed the high quality focalization and high efficency resulting from the combined implementation of CCT, CE and IF.