Load Torque Effects on the Critical Speeds of a Continuous Rotor

Abstract

The paper deals with the influence of the load torque on the critical velocities of a shaft mounted on short bearings. While in most works on this subject the load torque is taken as axial, it is shown here that, provided the external torque does not change its initial direction as the shaft is deformed and is applied through an ideal spherical coupling—the assumption of a semitangential mode is the correct one. Revised values of the critical torques and velocities are calculated accordingly and compared to those based on the conventional assumption.