Impact response and damage in laminated composite cylindrical shells

Impact response of a laminated composite cylindrical shell is determined both by the classical Fourier series and the finite element methods. Impact response determined by the finite element method also includes a prediction of the impact-induced damage deploying the semi-empirical damage prediction model of Choi–Chang. In the analytical method, the solution is obtained by means of an alternative numerical procedure incorporating the non-linear Hertz’s contact law which enables consideration of local indentation produced by the indentor on the impacted surface, instead of the Laplace Transforms technique used in an earlier work. The above procedure is also extended to the problem of impact on a cylindrical shell panel. The analytical procedure also provided information such as the natural frequencies of vibration of the impacted shell which helped in selecting appropriate mesh and time step sizes for the finite element method. A parametric study was carried out by the finite element method to determine the effect of varying the controlling parameters such as impactor mass, its approach velocity, curvature of the shell, on both the impact response and on the impact-induced damage. A reduction of the stiffnesses of the failed laminas on the impact response concurrently as the solution proceeded has also been incorporated.