Some new algorithms for locating a damage in thin plates using lamb waves

The aeroplane structures are aerodynamic complex shapes with multiple stiffeners attached to them. The presence of stiffeners poses complexity in the nondestructive evaluation of the aeroplane structures using guided (Lamb) waves. Thus, in the present study, this issue is addressed and resolved by carrying out experiments on a thin Aluminium plate with a stiffener using Lamb waves. In the present work, there are four piezoelectric wafer transducers, which are bonded onto the plate. These transducers have functions of generating and sensing Lamb waves in the plate. Authors have developed, two different algorithms for finding location of a damage in the plate by processing the data obtained from the experiments. The algorithms are named as Curve-Intersection and Sub-Quadrant methods based on their working principles. Thus, presented algorithms are capable of finding location of a damage in thin plate structures in the presence of stiffener using a minimal number of transducers.