EXPERIMENTAL INVESTIGATION OF SPARK ADVANCE AND AIR-FUEL RATIO EFFECTS ON ENGINE PERFORMANCE AND CYCLIC VARIATION IN HYDROGEN FUELED SPARK IGNITION ENGINE

In this study, effects of spark advance and air-fuel ratio on engine performance and cyclic variation in a hydrogen fueled spark ignition engine were investigated. A four stroke, single cylinder spark ignition engine having an L type cylinder head, was used. The engine was operated at constant speed of 1500 rpm, at two different fuel-air equivalence ratio and at various ignition timing conditions. In cylinder pressure data were used for prediction of engine performance parameters. Mean indicated pressure, indicated power, indicated torque, indicated efficiency, indicated specific fuel consumption and mass fraction burned values were calculated from the analysis of pressure data. The predicted results were showed that an increase in fuel-air equivalence ratio at lean conditions was resulted in a decrease in both volumetric and indicated efficiency and an increase of engine power as well as a decrease in cyclic variation. It was also found that the cyclic variations were originated mostly from flame development angle.