Rub-impact and Misalignment induced Vibration of HP Rotor System in Aero-Engine

Abstract

The numerical simulations of vibration induced by rubimpact and misalignment happening on the high pressure (HP) rotor system of an aero-engine are achieved, and also confirmed by experimental measurements on a special
designed test-rig. The simulation model of the rotor dynamics is set up by using of ADAMS, composes of both effective stiffness elements of two different elastic supporting and s rigid shaft. The local rub-impact happening between one disc and the casing shell, the front supporting misalignment are involved in the model. In the model, the rub-impact mechanism is expressed by the parameters of its stiffness and damping and friction, and the misalignment is simulated by changing the position of the front supporting. To change the running speed and the rub-impact or misalignment levels, the transverse vibrations of the discs and shaft of the HP rotor are calculated. The numerically simulated time-domain responses, the frequency spectra and the shaft-center trajectories are plotted and compared on the above different operating conditions. These simulation results are compared to explore the efforts on rotor vibrations of the rotating speed, rubbing stiffness or friction, and the misalignment displacement or angle. Finally, the simulation results are also consistent with the measured vibrations on the HP rotor test-rig, which confirms that the established model and simulation method and typical results are acceptable.