Research work relevance is concerned with global energy saving, alternative fuel use and environmental pollution reduction issues in wide world, which is especially important for the transport sector. Dissertation work presents study of efficient and ecological indicators, combustion process behaviour and its parameters of different gaseous fuels and their mixtures in the spark ignition internal combustion engine, which has such adaptations of duel fuel supply, gas direct injection or dual coil ignition systems. Different theoretical evaluations and analysis, experimental investigation and numerical simulation methods are applied in order to have a complex research, to suggest efficiency improving implements and to get a better understanding of gaseous fuels, like biogas, natural gas, hydrogen influence on the engine work cycle.
Introduction chapter presents the importance of the thesis, goal and the tasks of this work. In addition, scientific novelty, theoretical and practical significance of achieved results, defendable statements and authors pub-lished scientific papers presented in the chapter.
An overview of scientific literature according to thesis theme represent-ed in the first chapter. Different features, like fuel composition, lower heating value, chemical combustion reactions of different gas fuels were re-viewed according other scientist’s works and the influence of these indica-tors on engine efficient and ecological parameters and combustion behaviour were discussed.
Second chapter represents different research work methodologies, which were applied for the theoretical analysis and calculations, numerical simulation and experimental tests with different research type spark ignition engines.
Experimental test results of biogas, natural gas, natural gas and hydro-gen fuel mixtures, numerical analysis and simulation of mentioned gas fuels presented in the third chapter. Furthermore, test results of methane direct injection system with combustion process imaging and combustion light emission spectroscopy given in the result part. Research of different gas fuels and different types of fuel injection systems revealed that it is possible to achieve promising results, which are concerned with improved gaseous fuel combustion process, higher engine efficiency and lower exhaust gas emissions in spark ignition engine.
12 scientific papers according to the thesis subject have been published: one – in scientific journal, included in Thomson ISI Web of Science data base; two – in editions of international conferences, referred in Thomson Reuters data base Proceedings; four – in other international data base publications; one – in periodical reviewable scientific publication; four – in conferences materials
