Combustion Characteristics and Optimization of Neat Biodiesel on High Speed Common Rail Diesel Engine Powered SUV 2009-01-2786

Biodiesel is a nontoxic, biodegradable and renewable fuel with a potential to reduce engine exhaust emissions. Biodiesel used for the current work is jatropha methyl ester (JME). Earlier research, when biodiesel used in neat form, showed deterioration of performance when compared with diesel. The scope of current work is to match the existing diesel performance in all aspects, when the vehicle is fuelled by neat biodiesel (Jatropha). Matching diesel performance with biodiesel was done by remapping electronic control module. This results in power increase, but the vehicle emissions and noise level tends to increase. So tradeoff between performance and emission is achieved by optimizing the engine parameters.

Comparative performance was taken with normal diesel and biodiesel in neat form. Different engine characteristics like torque, power, thermal efficiency, exhaust temperature and noise along with emission such as HC, CO, NOx, and Smoke were studied. In engine, tests were done with Wide Open throttle (WOT) condition to know the extent of decrease in performance on entire operating region. Various vehicle performances such as drivability, noise, and current prevailing emissions are also studied. This enabled us to understand relative engine performance with these two fuels. In order to understand the variation on performance, a detailed combustion analysis was done with both the fuels. This was done by mapping combustion parameters by analyzing p-θ data. The relative combustion parameter like rate of heat release, duration of combustion and cumulative heat release were analyzed for both diesel and biodiesel.

The entire work shows the behavior of jatropha based fuel on vehicle and relates it to normal diesel usage. Based on this study, it is evident that the neat jatropha fuel gives benefits in emissions over diesel when optimizing the Engine Management System (EMS) properly.