| A brief review of the dispersion relations and Green's functions for cylinders is presented initially. Then a novel and computationally efficient numerical procedure is given for wave scattering by a circumferential crack in an isotropic as well as a laminated composite cylinder. By employing a wave function expansion in both the circumferential and axial directions, as well as symmetry and anti-symmetry decompositions, three dimensional wave scattering is reduced to two quasi-one-dimensional problems. This simplification greatly reduces the computational time. Illustrative numerical results are presented for the reflection and transmission coefficients of different incident wave modes in a steel cylinder and a laminated composite cylinder, each containing a crack having an arbitrary circumferential length and radial depth. They are shown to agree quite closely with available but limited experimental data.;The boundary element method is employed to analyze wave scattering by a crack that is oriented arbitrarily in an isotropic cylinder. However, computational data are presented for only two specific orientations that corresponding to an axial crack and a circumferential crack. A multidomain technique and 8-node quadrilateral elements handle the singularity introduced by the crack. Computed results show good agreement with limited available data. |
