Transport is an energy-intensive sector of the economy and it is important where energy comes from and how it is used - now and in the future. The presented research results seem to encourage further work, despite the fact that the work had the character of basic research. The results were achieved in idealized conditions by the fact that the internal combustion engine was tested in static conditions on the test bench and the fuels contained components with strictly defined parameters. These conditions are different from everyday life. However, the obtained results seem to be valuable as they lead to conclusions regarding biofuels, and these conclusions are not directly formulated and published in the literature on the subject. The general conclusion from the research carried out is that the introduction of the so-called biofuels can contribute not to the reduction of CO2 emissions, but to its faster balancing in the environment. This balancing can be achieved but at the cost of increased fuel consumption. This increase in fuel consumption would probably not occur if the "bio" components in the fuel were synthetic hydrocarbons obtained from biomass. However, proving it requires wider studies, including LCA. Data for this LCA, especially about a fuel consumption, may be coming from long term operation of vehicles.

The influence of the liquid cavitation on the elements of fluid‐flow machines can be removed in either an active or passive way. In this paper possibilities of reduction of the cavitation effect on the constructional materials in a passive way are described. Different methods of the material erosion wear description, depending on its properties, are discussed. A mathematical model, regarding the principal mechanical features of the material, is proposed. The mathematical model shows the relation between cavitation resistance of the material and its properties. The effect of principal properties of the material on its resistance on the liquid cavitation influence based on this model is discussed.

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Fast development of technology over the last decades has contributed to the adverse effects that may affect human health (both physical and mental). Such negative effects may include noise and vibration. These phenomena are accompanied by most of the technological processes. Need for more efficient and productive processes is causing rising trend in intensifying of these phenomena. It is unavoidable to increase efficiency without increasing the operating speed of machinery and equipment. The main goal of this paper is to carry out NVH (noise, vibration and harshness) analysis of engines; compression-ignition engine (diesel) and spark-ignition engine (gasoline) equipped in the same type of vehicle. But purpose is laying on presented methodology, not results of researches (but of course it will be presented too) which often (mainly) is made for failure detections. This paper will also cover influence of the engine mounting on generated acoustic vibrations followed by comparative NVH analysis of states occurring in diesel and gasoline engine. Scope of the work: a) theoretical introduction, b) presentation of vibration measurement (using LDV: Laser Doppler Vibrometry), c) NVH analysis in two types of engines, d) comparison of results, e) conclusions.

The paper regards the use of bio-blends consisting of vegetable oil and a higher alcohol as a new component of diesel fuel. The use of rapeseed oil as one of the components eliminates the need energy-intensive conversion rapeseed oil to esters. The use of higher alcohol, such as butanol second generation, obtained directly from biomass will be in accordance with requirements of the European Union on the promotion of renewable energy resources. Experiments with bio-blends were carried out with selected commercial fuel diesel, rapeseed oil, and two alcohols: iso-amyl alcohol and n-butyl alcohol. There was prepared two bio-fuel blends containing 20% by volume bio-blends (BM) and 80% by volume of diesel fuel (D). Comparison of physico-chemical properties of experimental mixtures were done. This article presents the qualitative characteristics of the new fuel composition and evaluate their compliance with the normative requirements. The summary highlights the need to continue research to improve fuel formulations, particularly in the selection of fuel additives.

The automotive industry is one of the fastest developing branches in the world. From year to year on the roads appear more and more cars. In the modern vehicles, better and more efficient technologies reducing exhaust emission are applied. However, the cars are still the leading source of air pollution, especially in towns and cities. Car exhaust gases have adverse effect on the human health, because they form so-called "low emission". It means that they are released into the troposphere at the people living height. As a result, people are exposed to the direct and long-lasting contact with the fumes. Therefore, precise assessment is very important to the vehicles' impact on the quality of the atmospheric air. The review of the evaluation methods of the impact of vehicles on the air quality was presented in the paper, with special regard to the mathematical dispersion modelling of the exhaust gases. In particular, NOx emission by sector in Poland, changing NOx emissions from road transport in Poland in the years 2000-2009 with regard to the change in the number of cars, vertical cross-section of a typical symmetric urban street canyon are presented in the paper.

This research reviews the impact on emissions from the engine fueled with the fuel containing a large share of bio-components, in particular with 30% n-Butanol. The research was carried out using a diesel engine. It has been shown that it is possible to achieve a double positive ecological effect concerning CO2 emissions. There was a decrease in CO2 emission from the engine with the fuel contained a significant share of bio-carbon. At the same time, NOx and Filter Smoke Number (FSN) emissions have been reduced together (FSN in large percentage). Usually, if NOx emissions are reduced, FSN increases, and vice versa. The paper shows also that the use of n-Butanol (bio, but nonfood) in the future is more effective than larger amounts of higher fatty acids methyl esters, although the full withdrawal of these esters seems unjustified.

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