Abstract: Using acoustic signature for nondestructive testing (NDT), relation between peturbation and acoustic signature of resonator is studed. The resonance frequencies and the field shapes of samples with or without crack are calculated by finite element method(FEM). Corresponding experiments are carried out for comparison and the results are conformed well. All of this are guide for NDT with acoustic signature inspection.

Key words: acoustic signature, perturbation, NDT, acoustic resonator