Application of reciprocity for facilitation of wave field visualization and defect detection

TL;DR

This paper demonstrates a method for visualizing wave fields and detecting defects in structures by applying elastodynamic reciprocity and guided wave mode extraction, improving defect detection robustness.

Contribution

It introduces a novel approach combining reciprocity and guided wave mode extraction for enhanced defect detection in structural components.

Findings

Reciprocity validity was confirmed under experimental conditions.

The maximum intensity projection method effectively detected artificial defects.

Wave field visualization revealed deformation at defect sites.

Abstract

The motion visualization in a structural component was studied for defect detection. Elastic motions were excited by hammer impacts at multiple points and received by an accelerometer at a fixed point. Reciprocity in elastodynamics is only valid under certain conditions. Its validity under given experimental conditions was derived from the elastodynamic reciprocity theorem. Based on this, the dynamic motion of the structural component was obtained for fixed-point excitation from measurements performed using multipoint excitations. In the visualized eigenmodes, significant additional deformation was observed at the wall thinning inserted as an artificial defect. To prevent the dependence of defect detection on its position within the mode shape, another approach was proposed based on the extraction of guided wave modes immediately after impact excitation. It is shown that this maximum intensity projection method works well in detecting defects.