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.
In this article the strength analyses of weights boxes are presented. Boxes are designed as a welded steel structure at which weights with total mass almost ten tons are stored in them. These boxes are an integral part of a mechanism intended for calibration of the mass measurement device. The article contains on one hand the basic scope of the theory of elasticity and strength analysis and on the other hand the numerical computations of the structure by using the Finite Element Method. Based on results the structure of weights boxes was modified in order to satisfy the defined safety factor.
The paper deals with specific aspects regarding the current development trends of electromobility in the context of road freight transport. The current system of electric vehicles for road freight transport and the relevant investigations are based on the experience with operating trolleybuses, which have the same power supply of traction motors from the overhead traction line by means of traction pantographs. As for the future, it has not been decided yet which electromobility-related power system will be used in practice, whether the supply of electric motors from traction lines or battery packs. In the introductory chapters, the manuscript discusses the fundamental information regarding the electromobility, current projects dealing with this issue, individual aspects and attributes related to these existing power systems, and their advantages and disadvantages in terms of their usage. In the most important part of the manuscript, the adequate evaluation is performed, as well as very recommendations for future research in a given topic are proposed.