Self-excited vibration caused by internal friction in universal joints (2nd report, effect of dynamic damper)

The effect of a dynamic damper on the self-excited vibration of a rotor system induced by joint friction is investigated both theoretically and experimentally. The system is such that two flexibly supported rigid shafts are connected by two Kardan joints and one cross-groove (CG) joint and loaded, and a dynamic damper is attached to the center bearing. The Coulomb friction in the CG joint mainly induces the self-excited vibration. As a result of investigation, it is found that the dynamic damper has a stabilizing effect on the self-excited vibration and expands the stable region for the system with the initial intersecting angle. The damper suppresses the vibration amplitude in the unstable region independent of the initial intersecting angle.