PARAMETERIZATION OF NATURAL MODES OF COMPOSITE ROTATING CONICAL SHELLS WITH MULTIPLE DELAMINATION

Abstract

This paper describes a comparative study on free vibration of bending stiff, torsion stiff and quasi-isotropic graphite-epoxy composite conical shells with single and multiple delamination. The finite element formulation is based on Mindlin's theory and multi-point constraint algorithm neglecting the Coriolis effect for moderate rotational speeds. Computer codes are developed employing QR iteration method to obtain delaminated natural frequencies under combined effect of twist and rotation. Mode shapes are depicted for a typical laminate configuration. The non-dimensional natural frequencies obtained are the first known results which could serve as reference solutions for future investigators.