Effect of Injector Opening Pressure on Performance and Emission Characteristics of Mahua Oil Methyl Ester in a Dl Diesel Engine

In recent years, there has been a considerable effort to develop and introduce alternative renewable fuel, to replace conventional petroleum based fuels. This led to the choice of non-edible mahua oil (MO) as one of the main alternative fuels to diesel oil in India. When MO was used as fuel in the compression ignition (CI), it results in lower thermal efficiency and higher smoke emission due to its higher viscosity and lower volatility. Hence in the present work, biodiesel was derived from MO using transesterification process and the effect of injector nozzle opening pressure (IOP) on the performance of the direct injection (Dl), CI engine was studied. The engine tests were conducted on a single cylinder, naturally aspirated, water cooled, diesel engine, which is used in the agricultural machinery, at different IOPs and loads. The engine performance with MO biodiesel was compared with neat diesel operation. From the engine tests, it is observed that the higher IOP of 200 bar results in better brake thermal efficiency and lower smoke, CO and HC emissions as compared to other IOPs. But there was a slight increase in the NOx emission at this IOP. The engine performance with the MO biodiesel results in lower CO, HC and smoke emissions and slightly higher NOx emission. Also the engine efficiency with MO biodiesel is close to diesel. From the present work, it is concluded that the biodiesel derived from underutilized and non-edible MO can be used as a renewable and alternative fuel for the CI engine with higher IOP, for the development of rural economy and for the energy security of India