Nonstationary Vibration during Acceleration through Two Critical Speeds : Maximum amplitudes and their rotational speeds

抄録

Taking account of damping effects, the nonstationary vibration during angular acceleration of a shaft through two critical speeds situated close together is analyzed theoretically, and both an exact solution and approximate expressions for it are derived. The results obtained from calculations of the exact solution show that the rotational speed at which the highest maximum amplitude will occur varies in a sawtooth manner above a certain acceleration rate, and that the highest maximum amplitude does not always decrease as the acceleration increases. A method for evaluating both the maximum amplitude and its rotational speed is proposed on the basis of the analytical results, and the evaluated values are compared with those from the exact solution.