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The limited quantities of oil reserves and the exhaust emissions from IC engines have become a threat to the existence of IC engines. One of the best solutions to the problem is the use of alternative fuels. Hydrogen is an alternative fuel that is called a fuel of the future. A disadvantage of hydrogen is its high combustion speed. Experimental results were used for the determination of inputs for numerical analysis. The numerical analysis is performed for a 3D model of the engine in order to determine the working parameters of the engine (pressure and temperature). The main goal of this study is to investigate a possibility of modifying the diesel engine so that it can run on hydrogen. It was found that in such an engine the greatest loads occur in the combustion chamber; thus, the vital parts of the engine are protected. Therefore, a mechanical analysis of the combustion chamber was performed (calculation of stresses and deformations). The obtained results are encouraging because they indicate that by applying the presented solution a much cheaper technology than the modern diesel engine systems is made possible.

In addition to different kinds of pollutants emitted by the vehicles, noise can also negatively effect on human health. It does not only threaten drivers, but also people living near major intersections and roads, as well as roads where traffic-flow is high. One of the biggest problems of the vehicle is the noise that occurs in the braking process. Despite the large scope of research into the development of brake systems, there are still no reliable procedures during the development phase to evaluate the robustness of these systems with respect to friction-induced vibrations. Therefore, the identification of the modal properties by using experimental methods has become even more important. Experimental and numerical modal analysis of the venting disc with radial ribs was performed in this paper. This approach enables the determination of the natural frequencies of the brake disc, as well as the verification of results obtained by the numerical methods. Changes in modal properties-resonance frequencies and modal damping values due to variation in operating conditions were also analysed.