On Unstable Vibrations of an Asymmetrical Shaft with Fluctuating Angular Velocity : 4th Report, The Effect of Gyroscopic Action on Unstable Vibrations

Abstract

This paper deals with instability for inclinational vibrations of an asymmetrical shaft rotating with a fluctuating angular velocity. For this rotor-shaft system, the equations of motion are derived and solved using an approximation which was previously proposed by the authors. As a result of the approximations ; the position of a widely unstable region caused only by shaft asymmetry moves to higher angular velocity as effects of the gyroscopic action become stronger. Furthermore, the position and width of instability regions caused by the coexistence of shaft asymmetry and an angular velocity fluctuation change markedly with the effect of gyroscopic action.