Vibration and stability analysis of a spinning shaft with arbitrary boundaries subjected to partial load

Abstract

This paper deals with the flexural vibration and dynamic stability of a spinning shaft subjected to partial load. Based on the theorem of moment of momentum and the theorem of motion of center of mass, the governing equation of motion for the spinning shaft system is obtained. Four kinds of boundary conditions including pinned-pinned, clamped-clamped, free-free, and elastic supports are considered. The exact whirl frequency equation is derived analytically for different boundary conditions. The obtained model is confirmed by comparing with the results reported in the available literature, and excellent agreement is presented. A numerical investigation is carried out to examine the effects of support stiffness, mass ratio, eccentric distance, and slenderness ratio on the whirl characteristics and stability of the system in terms of the obtained model. The results show that the whirl frequency and critical spinning speed of the system are dependent on these parameters, and the stability is mainly governed by the mass ratio and eccentric distance.

The lip motion trajectory of eccentric oil seal considering material viscoelasticity

“…Functioning as a rotary sealing component, the oil seal is primarily positioned between the principal shaft and the enclosure of the transmission system. Due to inherent installation deviations arising from the equipment's manufacturing process (Liu et al, 2022), coupled with the infrequent replacement of the principal shaft and the enduring influence of applied loads and gravitational forces over the shaft (Wang et al, 2023), the principal shaft and enclosure may eventually become misaligned, leaving the oil seal in an eccentric state. Sinzara et al (2018) conducted experiments using various rotational speeds to examine how changes in eccentricity affect friction torque, leakage rate, temperature and other performance parameters.…”