Affiliations: School of Mechanical Electronic Engineering, Harbin
Institute of Technology, Harbin, 150001, P.R. China
Abstract: The nonlinear dynamics theory is increasingly applied in the
dynamics analysis of tilting pad journal bearing-rotor system. However,
extensive work on system dynamics done previously neglects the influence caused
by the moment of inertia of the pad. In this paper, a comparison is made
between the responses of the rotor in the bearings with and without pad inertia
effect. Taking the Jeffcott rotor system as an example, the characteristics of
bearing-rotor system, such as bifurcation diagram, cycle response, frequency
spectrum, phase trajectories, and Poincaré maps, were attained within a
certain rotation rate range. The pivotal oil-film force of tilting pad journal
bearing was calculated by database method. The results directly demonstrate
that considering the influence of the pad moment of inertia, system dynamics
characteristics are found more complicated when rotor-bearing system works
around natural frequency and system bifurcation is observed forward when
rotor-bearing system works on high-speed range.
Keywords: Tilting pad journal bearing, nonlinear dynamics, pad moment of inertia
