Experimental study on a spark ignition engine fueled by CH4/H2 (70/30) and LPG

In the present study, a single-cylinder four-stroke SI engine was operated with LPG (C4H10/C3H8, 70:30), hydrogen and methane mixture (H2/CH4, 30:70). Experiments were conducted at excess air ratio between 0.8 and 1.5. Spark timing was varied from 14 to 35° CA BTDC under a constant load of 6 Nm at 1400 rpm.

► CNG/H2 (70/30) and LPG fuels are used in four stroke, single-cylinder SI engine. ► Brake thermal efficiency and emissions are measured at excess air ratio for changing the ignition time. ► Experiments were constant load and constant speed. ► Brake thermal efficiency values reached their maximum point when the excess air ratio was 1.15 and 1.22 for both fuel.