Full Waveform Simulation Method of Elastic Wave for Multi-layer Bonding Structure

Multi-layer adhesive structural materials are widely used in various industrial fields. The nondestructive testing(NDT) of multi-layer adhesive structure is usually realized by ultrasonic testing method, and the behavior of waveform of ultrasonic waves propagating in multi-layer structure can be predicted by numerical simulation of elastic wave. The numerical simulation includes building medium model and simulating the propagation. In this paper, based on the 2D staggered grid system, the multi-layer adhesive structure model is constructed, and the first-order velocity stress wave equation is solved by the finite difference method, and the propagation of elastic wave in the medium is simulated. Through experiment, the feasibility and accuracy of the numerical simulation method are verified by comparing the ultrasonic longitudinal surface echo of experiment and numerical simulation in both time and frequency domain.