Stability Analysis of a Flexible Bladed-Rotor

Abstract

In any high-performance turbo-machinery, instability prediction and damage are commonly occurring problems. The aim of this paper is to present stability analysis of a fully-bladed flexible rotor. The flexural vibrations of the blades as well as those of the shaft are considered; the energetic approach used includes the effect of the rotational inertia. Then stability detection, bringing loci veering phenomena and coalescence, in case of asymmetric rotor, to the fore, is made in order to determine a parametric domain where turbomachinery cannot encounter damages. Moreover, extensive parametric studies including for instance the length and the stagger angle of the blades are presented in order to obtain robust criterion for stable and unstable areas prediction. Finally, the rotor/stator contact is introduced and the effect of the radial load acting on the blades when rubbing against a carter is considered.