A Minimal Model-Based Approach for the Fast Approximation of Wave Propagation in Complex Structures

Abstract

Guided wave-based structural health monitoring is a promising technology to continuously monitor aircraft and to identify damage. The simulation of such structures is still a numerically challenging task due to their size and complexity. In this article, a minimal model approach is proposed to allow an approximate but very fast calculation of the wave propagation. The properties being relevant to the propagation of Lamb waves or in general guided waves are determined as part of the preprocessing. These include phase velocities as well as interaction parameters of all discontinuities. The minimal model consists of two steps to calculate a time signal at specific locations. First, a ray tracing algorithm determines suitable wave paths between two points in the reduced model of the structure. Second, wave packets of every incident ray are superimposed to synthesize a time signal. The obtained results are compared with both finite element simulations and experimental measurements.