Vibration of a Shaft Passing through Several Critical Speeds

Abstract

The transient vibration of a shaft passing through its several critical speeds at a uniform acceleration rate was investigated. The shaft is assumed to have a uniform section and be supported at both ends by springs and dampers. First, the free vibration of the system was analyzed to get the relationship between the damping given at the ends of the shaft and the modal damping ratio. Next, after evaluating the modal eccentricities and the modal damping ratios of the system, we calculated the maximum amplitudes of the shaft passing through the first and the second critical speeds at various acceleration rates using the approximate equations, which has been obtained from the analysis of the transient vibration of a system with one degree of freedom. Further, these calculated results were compared with the experimental ones.