Effect of boundary conditions on nonlinear acoustics used for impact damage detection in composite structures

Nonlinear Acoustics uses different types of nonlinear phenomena to detect structural damage. One of the major difficulties associated with this technique is the fact that nonlinearities can be produced not only by damage but also by various intrinsic effects such as material behaviour and/or structural boundary conditions. The paper investigates the effect of boundary conditions on Nonlinear Acoustics used for damage detection. A simple composite plate with impact damage is investigated. The plate is clamped using various force levels. The experimental study focuses on the effect of clamping force on vibro-acoustic interaction. The results demonstrate the importance of the effect of boundary conditions when nonlinear acoustics is used for impact damage detection.