The Effect of Temperature on Guided Wave Signal Characeeristics in a Honeycomb Composite Sandwich Structure with Disbond and Delamination

Abstract

Researchers developing guided wave (GW) based structural health monitoring (SHM) techniques frequently utilize amplitude and group velocity variations to detect and localize damage. However, external factors such as temperature and moisture can affect these features. To address this, a coordinated numerical and experimental study was conducted to investigate GW propagation characteristics in honeycomb composite sandwich structures (HCSS) with two types of damage: disbond and delamination, across a temperature range of 0° to 90° C. Computationally efficient two-dimensional (2D) numerical models were developed using COMSOL Multiphysics that takes into account a variety of temperature-related phenomena, such as thermal stresses and changes in the material properties of honeycomb sandwich and piezoelectric wafer transducers (PZTs). The amplitude and group velocity of the fundamental anti-symmetric (A0) mode are found to increase with disbond and decrease with delamination. Additionally, the normalised amplitude of the A0 mode linearly decreased with increasing temperature for both healthy and damaged cases. Given the A0 mode’s wide usage for damage detection, an adjustment equation for amplitude and group velocity with temperature change is proposed.