Abstract:

The modal reduction technique is utilized to a high order finite element model of flexible rotor systems with local non analytical bearing supports. Based on the finite element method and complimentary solution for the variational inequalities, an efficient numerical method for calculating the lubrication problem of the real bearings is presented, which calculates nonlinear forces and their Jacobian matrix simultaneously and obtains compatible accuracy with few increases of computing efforts. The periodic unbalance responses of the system are calculated by the Shooting method and their bifurcations are identified by analyzing the Floquet multipliers numerically. The numerical examples show that the schemes of this study not only save computing efforts greatly but also have good enough precision.

Key words: high or der local nonlinear systems, rotor -bear ing systems, finite element method