This research analyses the influence of some design features of an undercarriage of a tram on the energy efficiency in terms of mechanical energy losses during its operation. The work includes the comparison of results of the research from two main points of view, namely from a running gear design and a railway wheel design. Two variants of a tram’s bogie are investigated. A standard bogie and a bogie with a system that allows a radial adjustment of the wheelsets in curves. Two designs of a railway wheel are compared, a wheel with the traditional construction scheme and a wheel with a perspective construction scheme. The values of mechanical energy losses due to slippage in the contact between the wheels and rails are analysed. These losses are obtained with reference to a specific route and the value of the average power dissipated. Moreover, an analysis of advantages and disadvantages of bogie designs has made it possible to consider the most appropriate bogie design in terms of ensuring the energy efficiency. In this case, the bogie design with the wheels with the perspective construction scheme can be considered as the optimal option.

The paper is focused on a simulation of a railway freight wagon running on a test track with the given parameters. The railway freight wagon is running at different speeds and with different loads, at which the simulation is analysed from the point of view of derailment safety and lateral forces acting in the wheel/rail contact and individual bogies. The load distribution on the given railway freight wagon plays an important role in terms of the investigated parameters, and therefore it is compared, how the railway freight wagon behaves on the given track depending on a particular load distribution. The dynamic model was created in the SIMULIA – SIMPACK multi-body simulation commercial software. Components of a bogie were made in three-dimensional computer-aided design software and subsequently were imported into the multi-body simulation software. The theoretical foundations of the forces acting on the bogie, such as the vertical load, slip, or lateral forces of the wheelset, are covered and the test track is also described. The concept of derailment safety and the forces, that are essential for these parameters, are defined. The basic parameters of the given railway freight bogie are mentioned together with its most frequent use. The article also contains a description of a three-dimensional dynamic model of a freight railway wagon. The results are evaluated and compared for each speed and load distribution. The findings will be appropriate for advancing academic research and development.

In the conditions of the market economy and increased competition in the market of transport services, railway transport maintains an important position in the economy. Its main importance is due to technical and economic advantages over most other modes of transport. The main element of rail transport is rail vehicles, which must meet modern technical and economic requirements. Only competitive modern and progressive scientific technologies work effectively in a market economy. Traffic safety, technical and economic indicators of railway transport depend on the development of these technologies. The aim of this study is to improve the properties of a two-axle bogie of a locomotive as one of the main components on which the above-mentioned parameters depend. The commercial simulation software package Simpack was used for the research, in which MBS models of three types of bogies were created. Namely, there are modifications of the bogie considering a different distribution of the weight and different dimensions of chosen parameters. The first type of bogie is the basic one. This bogie is operated on railways. The other two are modifications of the first one, namely such parameters as the weight of separate parts of the bogie, dimensions of the bogie and wheelset, and location of the centre pivot. The research was conducted in terms of the derailment quotient, as one of the main parameters on which traffic safety depends, for different speeds and curve radii. After carrying out simulation calculations, the results were processed using Simpack post software. In all cases, the derailment quotient did not exceed the permissible value for all types of bogies. The best derailment quotient was for the third type of bogie, the derailment quotient of the second type was slightly overestimated in comparison with the other two but was still within the norm.

Rail vehicles are important transport means, which are used for transportation of plenty of passengers as well as tons of goods almost on all continents in the world. Railway transport represents an effective and sufficiently reliable kind of transport, mainly when it comes to electric trains. Increasing transport speeds together with relative strict requirements on safety and costs needed for operation, maintenance and repairing make high demands on operational properties of rail vehicles. They are especially demands on their dynamical properties, at which, a bogie is a key subsystem of a rail vehicle. This presented research is focused on investigation of dynamical properties of a rail vehicle bogie. Specifically, it is a locomotive bogie. It is a prototype two-axle bogie intended to be mounted on a newly designed electric two-bogie locomotive. The main objective of this work is to compare the selected output quantities of three variant solutions of a bogie. These variants differ to each other by values of the weight of bogie components, the weight distribution as well as the pivot pins distance. The article presents a comparison of two output quantities, namely yaw angles of bogies and deformation of springs in bogies. Parameters of a bogie and a locomotive have been provided by a commercial producer of locomotives. Numerical analyses have been performed for specific operational conditions defined by the running speed in a curved track. There have been performed the number of simulation computations for various running speeds and curve radii, at which, the article includes only the particularly chosen data.

The paper is a continuation of the authors’ research dealing with a sensitivity study of the wheel camber variation of the experimental vehicle Alfa Romeo 156. A numerical comparison of the wheel camber change versus vertical axle position has already been performed and published for the vehicle in question. The same methodology was applied to four other selected axle types (for the purpose of comparison with each other), represented by vehicles in which these axles are actually implemented. As a result of the research, the values of the camber and the forces acting on the wheels during the simulated cornering of the vehicle were determined. Subsequently, the influence of the kinematic parameters on the dynamic response of the vehicle was evaluated. The current work of the authors focuses on experimental runs performed on the real vehicle (Alfa Romeo 156). Accordingly, the data from the experimental runs are compared with a numerical simulation of the passage of the modelled vehicle. The aim of this research is to evaluate the magnitude of body roll and body pitch for the vehicle slalom manoeuvre. The results indicate an excellent correlation between the numerical results and the measured values for this manoeuvre. On the basis of these results, it can be concluded that the numerical simulations are predictive, a finding that is crucial for developers pursuing equivalent kinematic parameters. In addition, the predictive nature of the simulation program allows to simulate diverse manoeuvres (e.g. vehicle braking) with variable input parameters, which would be problematic to implement in the case of experimental runs. Reducing the development time and tuning time of a prototype vehicle is one of the key factors to the competitiveness of companies.