Dynamic Modeling and Analysis of a Freight Train Vertical Vibration Reduction System

Abstract

Abstract Based on wheel-rail impact vibration and considering the body stiffness and natural damping, this paper builds a three-degree-of-freedom vibro-impact system model for freight train’s vertical vibration reduction system. The dynamic behavior of the system is analyzed. The Poincaré map of the system is determined by the analytic solution of the system derived from the motion differential equation of the multi-degree-of-freedom vibro-impact system combined with Newton’s second law. It is found that the fork bifurcation, Hopf bifurcation and other dynamical behavior leading to Chaos when the system parameters are changed. In the process diagram, fork bifurcation is easier to be observed by engineers than Hopf bifurcation and can be easily applied to the control strategy of semi-active suspension. The dynamic parameters of the train are optimized to avoid chaos in the train operation, reduce the vertical vibration of the train, improve the stability of the train operation, and provide the theoretical basis for the vibration reduction design of the train.