Delamination Buckling of Composite Conical Shells

Conical shells are most useful in primary aerospace structures owing to their aerodynamic shape and form the foremost portion of flight vehicles experiencing severest drag forces. Delamination raised during the production process or during usage would adversely affect the structural integrity of the shell structure. In the present paper, finite element modeling of delamination embedded in composite conical shells subjected to axial compression is carried out in line with the procedure available in published literature. Layered shell element has been used and the effect of delamination length & depth on the structural integrity of conical shell is studied. Study has been carried out for isotropic and orthotropic materials. Verification of the methodology is carried out by comparing with published literature on composite cylindrical shells. Global as well as local buckling mode shapes have been observed during the simulation. The linear bifurcation buckling load of first mode is considered as the critical load under axial compression. The critical load is normalized with respect to critical load of intact conical shell. The normalized critical load is illustrated graphically against the normalized length of delamination. Consistent pattern has been observed for isotropic and cross ply configurations. Further analysis is required for angle ply configuration.