A Mixed Shell Element for Cambered Helicoidal Blades and Dynamic Stresses due to Aerodynamic Excitation

Abstract

An eight noded mixed shell element for the vibration analysis of rotating cambered helicoidal blades is presented. The strain displacement relations of Gol den'veizer are used and Reissner's functional is adopted in deriving this element. The effect of initial in-plane stresses is also included. Also, expressions for the pressure difference between the pressure and suction profiles of the rotating blade are derived from two dimensional thin airfoil theories of a stage. The forces thus obtained are applied on the blade to determine the dynamic stresses.