Coupled Vibration Analysis for Bladed Disk Assemblies and Flexible Shafts : 1st Report, Irrational Condition

Abstract

This paper is concerned with coupled vibration between flexible bladed disks and flexible shafts in the application of the Finite Element Method. since a bladed disk is considered as a periodically symmetric structure, it is enough to analyze one periodic substructure of a bladed disk by the use of the Cyclic Symmetry Method. In this paper, it is assumed that only one nodal point at the center of a bladed disk is connected with one nodal point of a shaft. The followings are known through this study. (i) Natural modes of zero nodal diameters generated on a bladed disk are coupled with longitudinal and torsional vibration of a shaft. (ii) Natural modes of one nodal diameter generated on it are coupled with only lateral vibration of a shaft. (iii) Natural modes of more than two nodal diameters generated on it are uncoupled with vibration of a shaft completely.