Modal uncoupling of damped gyroscopic systems

A new approach for uncoupling the equations of motion typical for rotordyna mical systems is presented. The method does not neglect the speed-dependent effects, such as gyroscopic effects, and can be particularly valuable in t he controller design of actively controlled rotors. In the presence of hyst eretic type of damping, the resulting uncoupled gyroscopic systems come wit h an equivalent viscous damping, equivalent in a sense of yielding the same natural frequency and decay rate. The approach is illustrated through thre e examples of technical interest: a Jeffcott rotor with hysteretic damping, a Stodola-Green rotor, and a rotor of a small gas turbine. The generated r esults demonstrate that the developed approach is correct and straightforwa rd. (C) 2001 Academic Press.