Performance and emission characteristics of papaya seed oil methyl ester-n-butanol-diesel blends on a stationary direct-injection CI engine

Currently, atmospheric pollution and increased energy needs delineate the importance of alternate sources of fuels. In this current study, the performance and emission characteristics of papaya seed methyl ester (PSME) blended with diesel are studied at varying loads. PSME is blended at 5, 10 and 15% into the fuel and, in addition to that, a 10% concentration of n-butanol is also blended. The blends showed promising results where the CO, HC and smoke emissions were reduced significantly by addition of n-butanol despite the higher viscosity of papaya seed oil. Also, the effect of n-butanol addition was high in blends with lower concentration of biodiesels. Their effect was found to be predominant at medium operating loads rather than at lower and higher loads. In addition to that, PSME increased the brake thermal efficiency (BTE), exhaust gas temperature (EGT) and NOx emissions.