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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.

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The braking system is one of the important systems from the aspect of vehicle safety, but it is also one of the systems that has a significant impact on the environment. Brakes are considered to be a source of non-exhaust particles, that is sources that create particles by the wear of the elements that are in contact with each other, and in this case, the brake friction elements (brake pads and rotating disc). Such particles often contain heavy metals that are part of the friction elements. There are a number of influencing factors that can affect the wear of the friction elements and increase the concentration of the formed particles. Laboratory methods of testing wear and particle formation, road tests and various simulations of brake wear are most often used for testing. In this paper, a review of methodologies for testing the formation of particles from the braking system, the materials used in the composition of the friction elements of the brake, as well as factors affecting the wear rate and concentration of particles of different sizes, based on the conclusions of other authors is presented. Based on this review, it can be concluded which quantities and factors need special attention during further research in the mechanism of formation of non-exhaust particles whose source is the vehicle braking system.

Brake is a device for slowing or stopping the vehicle. The sound that occurs in the process of braking is very irritating for the driver. Brake systems of road vehicles as important factor in overall vehicle noise have attracted great attention. All global brake system manufactures are focused to the quieter brakes. This paper presents an analysis of differentially variants of brake disc, and how the structure itself influencing the occurrence of noise. The weight of analyzed discs is approximately equal to each other. The analysis was performed in the software package ANSYS, while the model was created in CATIA.KEY WORDS: noise, brakes, manufactures, structure, modal analysis UTICAJ OBLIKA REBARA NA VISOKOFREKVETNU BUKU VENTILIRAJUĆIH DISK KOČNICA TERETNIH VOZILA REZIME: Kočnica je uređaj za usporavanje ili zaustavljanje vozila. Zvuk koji se javlja u procesu kočenja je jako iritirajući za vozača. Veliku pažnju kod drumskih vozila upravo su privukli kočni sistemi kao važni faktor u ukupnoj buci vozila. Svi svetski proizvođači kočnica su se usmerili ka tišim kočnicama. U radu je prikazana analiza za različitie varijante disk kočnica, odnosno kako sama konstrukcija utiče na pojavu buke. Analizirane varijante diskova su približno istih masa. Analiza je izvršena u softverskom paketu ANSYS, dok je model izrađen u CATIA.

The braking system is one of the most important elements in vehicle systems from the aspect of vehicle safety, besides the steering system and the internal combustion engine. During the braking process, the disc and pads absorb a large amount of kinetic energy that converted to heat. Owing to this frictional heating, it is necessary to compute the temperature distribution that will be appeared during the braking process, which is the main goal of this research paper. There are many factors that can be influenced to the distribution of frictional heat generated. One of the significant factors is the applied pressure by the brake pad on the braking disc. The results proved that when increased the applied pressure then the frictional heat generated increased too. It was developed a new finite element model based on observed data from real vehicle. It was used ANSYS/WORKBENCH 14.5 software to perform the numerical analysis, module Transient Structural. Parts that are the most disposed to the thermal stress are braking pads. Also, it was found time period from 0 to 0.1 second is the most critical period during the whole braking period, because in this period, temperature rises rapidly, the maximum temperature occurred at 1.338 seconds, and after that it falls.