A Transfer Matrix Technique for Evaluating the Natural Frequencies and Critical Speeds of a Rotor With Multiple Flexible Disks

Abstract

The influence of disk flexibility on the rotordynamical behavior of turbomachinery is a topic that is of some concern to designers and analysts of such equipment. Research in this area has indicated that disk flexibility may significantly alter the dynamical behavior of a rotor system. This research effort is concerned with developing a procedure to account for disk flexibility which can readily be used for investigating how such effects might influence the natural frequencies and critical speeds of practical rotor systems. A transfer matrix procedure is developed in this work in which the disk flexibility effects are accounted for by means of additional terms included in the transfer matrix formulation. In this way the efficiency and practicality of the transfer matrix method is retained. To demonstrate this technique, a simple rotor system is studied for the effect of disk flexibility and the results discussed.