Biofuels represent one of the alternatives to obtain the CO2-neutral propulsion of IC-engines. Butanol, which can be produced from biomass, is considered and was investigated in the last years due to the very advantageous characteristics of this alternative fuel. Butanol can be easily and irreversibly blended both with light (gasoline) and heavier (Diesel) fuels. Comparing with ethanol it has the advantages of: higher calorific value, lower hygroscopicity and lower corrosivity. It can replace the aviation fuels. This paper presents the emission results obtained on two Diesel passenger cars with different technology (Euro2 and Euro6c) and with addition of Butanol to Diesel fuel, as a part of the research project DiBut (Diesel and Butanol). Interesting results are given about some non-legislated (non-regulated) components, Acetaldehyde (MeCHO) and Formaldehyde (HCHO) and about the PN-emissions with/without DPF.

The article presents the numerical analysis of a single-cylinder gasoline engine with indirect injection and spark ignition. The goal is to recognize and analyze gas flow through inlet and outlet valves and channels. These data were obtained from the simulation of a four-cycle engine cycle without combustion of the fuel-air mixture. The simulation was carried out in ANSYS, using a dedicated IC Engine module. After the simulation, the result was analyzed on the cross-sectional plane of both the valves and the combustion chamber. This method provided the necessary and concise representation of the flow characteristics. Five separate stages are presented - two describing the different displacement of the valve for each inlet and exhaust stroke and one representing the phenomenon of overlapping. The type of flow, its speed and tendency to create turbulence are described

Turbulent Jet Ignition systems are mainly dedicated to the combustion of lean mixtures of natural gas in heavy duty engines. The use of such a system in combination with lean mixtures leads to an increase in its overall efficiency. The article presents simulation analyzes of the impact of the excess air coefficient occurring in prechamber on the combustion process: combustion indicators and emission indicators. Tests on a single-cylinder engine with a displacement of about 4 dm3 at medium mixture (IMEP = 1.0 MPa) were carried out using the AVL Fire software. It was found that the incineration of global lean mixtures (lambda = 2) is effective when initiating this process (in the prechamber) with a charge of a stoichiometric composition. A strong relationship was found between the thermodynamic indicators in both prechamber and main chamber and the excess air coefficient initiating combustion.

The article presents a diagnostic and reliability model of an internal combustion engine that allows to assess the reliability status of the engine’s systems for a two-state model of operation and maintenance: functional – failed. The proposed diagnostic model is a qualitative-quantitative probabilistic model combining the reliability states of the engine systems with the values of the vibroacoustic diagnostic signal parameters. The conducted diagnostic and reliability experiments and simulation tests showed that based on the developed diagnostic and reliability model, it is possible to determine the reliability states of the engine.

The article presents issues related to the drivability and stability of a vehicle equipped with electric motors placed in the hubs of wheels. In the article was presented the necessary modifications to the vehicle and their impact on the vehicles motion parameters. Describes the behavior of the vehicle on a homogeneous surface and on surfaces with different adhesion coefficient under the wheels of the vehicle sides. The simulation model is presented. The last part of the article presents simulation results for compared surfaces with different adhesion under the wheels of the left and right side of the vehicle.

Modernization of passenger cars and constant development of existing legislation lead to a reduction of exhaust emissions from these vehicles. In accordance with package 3 of the RDE test procedure, the European Commission has extended testing methods by including exhaust emissions during a cold start. The article compares the research results on the impact of ambient temperature during the cold start of spark-ignition and compression-ignition engines in road emission tests. The tests were carried out in line with the requirements of the RDE test procedure for passenger cars meeting the Euro 6d-Temp emissions standard. The obtained results were analyzed, i.e. there were compared the engine and vehicle operation parameters and the values of road exhaust emissions, during the cold start of gasoline and diesel engines at the ambient temperature of approximately 25oC.The summary presents the share of cold start phase of a passenger car (at the ambient temperature of around 25oC) for each exhaust emission compound in the urban part of the test, and in the entire RDE test, depending on the engine type used.

The elements creating friction pairs are described to be very difficult in terms of determining all optimal parameters in an unambiguous manner. The nowadays research on stability of friction pairs is focused on the surface and the top layer of surface. The main goal is find new design solutions and materials, achieving a lot of kilometers to main repair in combustion engines. The biggest structural difficulties are noticeable in friction pairs where can be observed sliding and returning motion, what is connected with sealing function. A typical example of such pair is piston ring – cylinder. Engineers work on defining an additional factor that would be able to gain the reduction of tangential force by reducing the friction coefficient in elements of friction pair. Molecular structure and nature of the bonds between the molecules presented in the material, result that the free surface energy may be such a factor, because determines the tribological properties of the material, what is reflected in the stability of the units. The work carries out of an analysis after research on the goniometer in the presence of water and diododomethane that allowed to measure wetting drops on the surface, thanks to which can be calculated surface energy. Within this work will be performed study of the energy state of the surface of piston rings with a coating including a diamond powder. After analysis on the basis of the collected measurements will be developed conclusion regarding the potential relationship between the free surface energy and wearing of the material.

The article presents the results of preliminary tests of the vehicles powertrain with fuel cells, carried out in a thermoclimatic chamber in a reduced temperature box. The aim of this research is to facilitate the introduction of this type of vehicle to the market and guarantee correct operation in changing climatic conditions. In tests, the use of a new type of vehicle drive system and the use of hydrogen as a commonly available fuel is of great importance.

To avoid the negative effects of increasing the amount of RME in the diesel fuel (to 10%), three different additive packages were used: stabilising, cleaning, and increasing the cetane number with different concentrations. The tests were carried out using a 4-cylinder, turbocharged 1.9 TDI engine from VW. The tests were carried out for 4 fuels (comparative fuel with a content of 7% RME and 3 test fuels with a content of 10% RME, differing in the content of the additive package.It was found that each of the 3 additive packages used does not have a significant impact on fuel consumption. However, a different effect of the tested additives on the composition of exhaust gases was observed. The first package had a slight effect on reducing the NOx concentration in the exhaust, but only for small engine loads. On the other hand, the second additive pack worked more effectively only at higher engine loads (in relation to the reduction of NOx concentration in the exhaust gases). In the third packet, the amount of the cetane additive was doubled (compared to the second packet). Then, the reduction in the NOx concentration in the exhaust gas by 3–8% was obtained with reference to the comparative fuel.

Modifications of standard fuel system for an industrial gas engine and an analysis of the engine operation on low quality fuel have been described in this paper. The implemented fuel system modifications aim to overcome the challenges which arise when standard fuel gas is replaced by low quality one. Analysis focuses on stability of mixture formation esp. on variations in gas distribution for each cylinder of the engine. The results and discussion include also emissions optimization impact on efficiency as well as the efficiency and emissions level dependency on fuel type.