On the Forced Vibrations of the Shaft Carrying an Unsymmetrical Rotating Body : Response Curves of the Shaft at the Major Critical Speeds

Abstract

A shaft carrying an unsymmetrical rotating body is statically unstable near its major critical speeds, and the unstable regions become smaller as damping forces are larger, and they vanish when the damping coefficients reach critical values. These critical damping coefficients c_c1, c_c2 are given in the present paper. Then, the amplitudes and phase differences of forced lateral vibrations are studied ; they are found to depend very much upon angular positions of static and dynamic unbalances. The characteristics of the response curves and phase differences are very different from those of a usual vibratory system. Furthermore, comparison with a flat shaft system is made.