Finite Element Modelling of Rotors, Without Considering the Shear Effects

Abstract

The proposed rotor model is based on the finite elements of a Timoshenko beam, whose support is rigid and fixed. It takes into account the geometric asymmetry of the discs and/or the shaft, while neglecting the shear effect. The equations of motion obtained include time-varying parametric terms that can lead to lateral dynamic instability. The influence of the combined rotational and translational movements of the support is analyzed by the Campbell diagram and the rotor stability map. Critical speeds according to modes have been identified.