Modal Analysis of a Compressor Disk

Abstract

The compressor disk is one of the key parts of the aeroengine. Its structure and strength play an important role in the reliability of the compressor. Most of the damage are caused by resonance stress. At the same time, the dynamic design and analysis of the key components are required because of the rotating state. When the compressor disk is in normal operation, the disk rotates around the rotating shaft in a large scale. Centrifugal inertia force will affect the deformation of the structure, and induce a certain change of natural frequency when compared to the static condition, which has increased complexity to modelling and numerical calculation. In this paper, the effect of dynamic stiffening on the vibration characteristics of disc is studied. In order to derive the equations of motion, Hamilton’s principle is used, and the boundary conditions are obtained at the same time. We studied the natural frequency of the isotropic plate and laminate plate by Ritz method. Using the popular finite element analysis software ANSYS, we carry on simulation computation of vibration modes on a certain type of compressor in the working process. Besides, by investigation of the influence of structure parameter and rotating speed on the forward travelling wave and back travelling wave, we studied the critical speed of the compressor disk, which is essential in the rotator.