Effect of Rotary Inertia and Gyroscopic Moments on Dynamics of Two Spool Aeroengine Rotor

Abstract

The main objective of the paper is to study the effect of rotary inertia and gyroscopic moments due to lumped masses on the dynamics of two spool aeroengine rotors. Since the rotary inertia effect is well established, the thrust of the paper is on the effect of gyroscopic moments. Quantitative as well as qualitative aspects are studied. Effect of gyroscopics and rotary inertia on rotor critical speeds and unbalance response are studied for several rotors with particular reference to relative LP and HP rotor speeds. A two spool rig which resembles an actual aeroengine has been designed and built. Experiments have been conducted on two configurations of the rig in order to verify the theoretical results obtained by a formulation developed using the method of extended transfer matrices, for the two spool rotor with two intershaft bearings. A reasonably good correlation between the theoretical and experimental results is observed.