USE OF NON-DEGENERACY IN NOMINALLY AXISYMMETRIC STRUCTURES FOR FAULT DETECTION WITH APPLICATION TO CYLINDRICAL GEOMETRIES

A novel technique is proposed for the detection of localized flaws in otherwise axisymmetric structures. The technique is based on the split-mode phenomena that occurs when the degenerate vibratory modes of the axisymmetric structure become non-degenerate due to the flaw with altered mode shapes and shifted natural frequencies. A basic theoretical motivation is offered and computational and experimental studies on cylindrical structures are reported that verify the premises of the proposed methodology and provide an assessment of its specificity and sensitivity under confounding conditions, such as out-of-roundness.