Chapter 9 - Studies on pongamia oil methyl ester fueled direct injection diesel engine to increase efficiency and to reduce harmful emissions

Abstract

The present work investigates the combustion, performance, and emission characteristics of a single-cylinder diesel engine using biodiesel (Pongamia methyl ester) with three different blends by varying the nozzle opening pressures and analyzed the effect of diethyl ether blends at different loading conditions. It was observed that the nozzle opening pressure at 220bar showed a slight reduction in the brake thermal efficiency by around 5.3% while a 25.7% reduction in exhaust smoke level with a 7.2% increase in oxides of nitrogen concentration at the rated power output was noticed. The results also showed a significant reduction in nitrogen oxides (NOx) and smoke emissions for neat biodiesel with 10% DEE blend when compared with neat biodiesel at the rated power output conditions with DEE blends at the rated power output. Decrease was found in peak pressure and heat release rate, as well as ignition delay. Further, the effect of the thermal barrier coating on the piston crown with a ceramic material (TiO2) of about 0.5mm, by plasma spray method was also analyzed. The results of this analysis revealed an improvement in brake thermal efficiency (BTE) and the brake-specific energy consumption as compared with B20 fuel engine at the rated power output. It was concluded that biodiesel with 10% DEE blend showed better results with respect to efficiency and emissions as compared with the biodiesel with 220bar nozzle opening pressure. Further, it was also found that the TiO2 ceramic coating could be applied successfully without requiring any modifications in the engine with marginal reduction in the performance and significant decrease in the harmful emissions.