Effect of Ignition Timing and Compression Ratio on the NOx Emission and Performance of Hydrogen Fuelled SI Engine

In this study, effects of spark advance and compression rate on engine performance and nox emission in a hydrogen fueled spark ignition engine were investigated. the engine was operated at constant speed of 1600 rpm, at equivalence ratio of φ=0,6, at wide open throttle, at four different compression rates and seven different spark advances. in cylinder pressure data were used for prediction of engine performance parameters. mean indicated pressure, indicated thermal efficiency, indicated specific fuel consumption and mass fraction burned values were calculated from the analysis of pressure data. it was observed thatdelayedor excessiveignitionadvance reduced engineperformancein spark ignitionhydrogenengine. on the other hand, increased compression ratio decreased the combustion duration and increasedtheengine performance, butthe emission of nox was effected adversely.