The influence of time-varying mesh stiffness on natural characteristics of planetary gear system

Abstract

Abstract Modal property is the crucial factor that can influence the vibration characteristics of the planetary gear system. Previous studies used time invariant mesh stiffness (TIMS) to study the natural characteristics. However, with the rotation of the gear, the meshing stiffness will change periodically which will lead to changes of modal properties. Based on these properties which are ignored in previous studies, a translational-torsional free vibration model base on time-varying mesh stiffness (TVMS) rather than time invariant mesh stiffness (TIMS) is established in this paper to study the modal properties of the planetary gear system, the effects of TVMS on the natural characteristics are investigated. The results show that the meshing phase difference and the change regulation of the time varying natural frequencies are correlated, and there is a dramatic variation of higher order natural frequencies at the contact teeth change points. Furthermore, a useful conclusion can be drawn that takes TVMS to calculate higher order frequencies has certain advantages over traditional methods.