The Influence of Truck Construction Errors on the Running Stability of a Railway Vehicle : 2nd Report, Hunting Motion Damping Ratio and Limit Cycles

Abstract

By making use of the contour representation of the damping ratio, the influence of the wheelset misalignment on the stability of the wheelset hunting motion can be shown much more clearly, and it is found that the wheelset misalignnmnt diminishes the stability margin in the high speed range, and that, in the (k_x k_y) plane, k_x and k_y, are better to be chosen in the region apart from a straight line, k_y=1.5k_x. Limit cycle analyses by means of numerical integration of the original nonlinear equations of motion show that, as no unstable limit cycle can be found in the stable region of the (k_x, k_y) plane, it can be said that, in order to analyze the stability of misaligned wheelset motion, it is sufficient to examine the stability of the linearised system.