This article deals with computer analyses of output quantities of a railway vehicle depending on changing of parameters of suspension system. A passenger car was chosen for dynamic analyses. An analysed passenger railway vehicle uses two stage suspension system composed of coil springs and hydraulic dampers. Stiffness of coil springs of primary and secondary suspensions were defined for two states and its influence on output values in terms of quality and quantity was evaluated. As output variables, values of forces in a wheel/rail contact and accelerations in several locations on a wagon body floor were chosen. Values of forces in a wheel/rail contact indicate dynamic response of a railway vehicle running in terms of running safety and values of accelerations serve as important input for evaluation of passenger ride comfort.
The railway transport network is currently in a quite big expansion. Therefore, railway tracks are modernized and the attention is given also on the technical state of rail vehicles, which operate on them. However, it may happen that the wheel surface is damaged. One of the most common reasons of wheel damage is too much braking, which results to the wheel-flat formation. This article is focused on the evaluation of the influence of a rail vehicle running on the railway track, which a wheel is damaged by the wheel-flat. Investigation of these negative effects was performed by means of simulation computations. As evaluating parameters, values of the wheel force in the contact of the rail and wheel with a flat where observed.