Experimental investigations on DI (direct injection) diesel engine operated on dual fuel mode with hydrogen and mahua oil methyl ester (MOME) as injected fuels and effects of injection opening pressure

The influence of injection opening pressure (IOP) for 20% blend (B20) of mahua oil methyl ester (MOME) and 22.5 liters per minute (lpm) of hydrogen dual fuel mode was investigated based on the performance, combustion and emission characteristics of a single cylinder, four stroke, direct injection (DI) diesel engine with a rated power of 3.5 kW at a rated speed of 1500 rpm. Experiments performed at four different IOP of 200, 225, 250 and 275 bar that were compared using the diesel operation at 200 bar as the baseline. Maximum brake thermal efficiency, minimum brake specific fuel consumption, and lowest HC, CO and smoke emissions with increased concentration of NOx were obtained at IOP of 250 bar for B20-hydrogen dual fuel mode. Further increase in IOP to 275 bar results in decreased brake thermal efficiency, increase in HC, CO and smoke emissions whereas the concentration of NOx slightly diminished. Present investigations revealed that the IOP of 250 bars for 22.5 lpm hydrogen with B20 dual fuel mode is optimum.