Vibration of cantilevered laminated composite shallow conical shells

This paper presents a new mathematical model to investigate the free vibration of laminated composite shallow conical shells in an effort towards accurate modelling of turbomachinery blades. The shells are composed of symmetrically or unsymmetrically laminated composites. This study focuses on E-glass/epoxy conical shells with four and eight-ply laminates, but the analysis can be easily extended to any composites with an arbitrary number of plies and fibre orientation. The energy integral expression is derived on the basis of the shallow shell theory incorporating variable chordwise surface curvature. A global computational approach based on the extremum energy principle is employed to derive the eigenvalue equation. A flexible, admissible global shape function is developed to account for the geometric boundary conditions. Previously unavailable frequency parameters and vibration mode shapes are presented. 0 1998 Elsevier Science Ltd.