| With atmospheric pollution becoming more and wore serious and petroleum, deposits on the earth becoming less and less, people are being awake to the more urgent necessity for finding clear alternative fuel than ever. Hydrogen is a renewable clear energy, and it can be applied in lots of cases. Hydrogen energy also exhibits ideal characteristics as fuel for internal combustion engine. Therefore, systematical research on a hydrogen ?fueled engine is not only a initiating event, but also the basis of practical use for hydrogen ?fueled automobiles.In the first chapter of this dissertation, the state of the arts of development of hydrogen energy, and the use of hydrogen fuel in automobiles are overviewed in detail. In the second chapter, firstly, based on the analysis of theoretic cycle of hydrogen engine, the relations between state parameters in four strokes are established. Moreover, the expressions of the mean index pressure and thermal efficiency are showed, and the effect of operative parameters and structural parameters on them are analyzed quantitatively. Lastly, the comparison of the mean index pressure and thermal efficiency between hydrogen engine and gasoline engine are made. The researches on theoretic cycle lay the basis for researches on practical cycle of hydrogen engines.As rapid development of calculating algorithm and computer hardware, the researches on combustion calculation model are being put more attention, and it has been becoming useful method for analyzing the combustion process of engines. But, the research on combustion calculation model for hydrogen?fueled engines has not still been engaged. In the third chapter of this dissertation, based on the physical and chemical properties of hydrogen and the combustion characteristics of hydrogen, the quasi - dimension combustion calculation model of hydrogen ?fueled engine is set up through analyzing the characteristics of turbulence flame and chemical reaction kinetic of hydrogen ?air mixture. The model includes the dual ?area thermodynamics sub - model, quasi - dimensional turbulent entrainment combustion sub ?model, turbulence flame promulgating sub ?model, hydrogen - air mixture chemical kinetic sub - model and loss of heat transfer sub - model and so on. Besides, the calculating algorithm is also given. The temperature of burned and unburned areas, rate of heat release, pressure in- cylinder and the thickness of compositions in running process of engine can be calculated by the model, the calculated results are accord with the measured results in a hydrogen ?fueled engine.The researches on combustion in hydrogen ?fueled engine are being carried out in developed countries. Some researches on hydrogen ?gasoline dual fuel engine have been conducted in china over the years. But, the systematical researches on combustion of hydrogen - fueled engine should also been made in china. In the fourth chapter of the dissertation, on the basis of experimental researches for hydrogen- gasoline dual fuel engine, the researches on the form of the hydrogen- air mixture and effect of structural and operating parameters on the form of mixture and combustion has been conducted. Besides, the reasons of abnormal combustion, as well as form of NOX have been analyzed, and the measures taken for reducing NOX emission and for eliminating abnormal combustion have been discussed. Moreover, it has been pointed out that the hydrogen engine used in ?cylinder injection with high pressure can increase volumetric efficiency and compression ratio,-therefore, the performance indexes in this engine, such as output power, thermal efficiency, range of thickness of mixture with normal operation and NOX emission, can be improved, and it is possible for the engine to realize rapid combustion of thin mixture, so abnormal combustion, such as backfire, pre ?ignition, can be controlled effectively. Finally, the experimental results show that ignition timing, injection timing and injection duration have great effect on the performances of the engine. So thes...
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