Optimization of nozzle hole number for a diesel engine fueled with kapok methyl ester blend

It is evident from the past investigations that the biodiesel improves the quality of combustion and elevates the thermal efficiency. But the inevitable fact that enhanced combustion quality enhances NOx emissions. This works aims at decreasing NOx emissions by changing the injector hole number (IHN) so that the wall impingement may be reduced which would reduce the NOx emissions. The experiments are conducted for three different nozzle configurations (four holes, five holes, and six holes) for three different kapok methyl ester blends (20%, 30%, and 40%) for three loads. The Performance and emission parameters are optimized using a 3*3*3 matrix (load, biofuel blend, and IHN). As expected results indicate reduction of NOx with increase in IHN. CO, HC, and smoke also see a mild decrement with increase in IHN. Brake-specific fuel consumption (BSFC) decreases with increase in IHN whereas slight increase of BSFC is observed with increase of fuel blend.