EXPERIMENTAL INVESTIGATION ON A DIESEL ENGINE FUELLED WITH NEEM OIL AND ITS METHYL ESTER

Fuel crisis and environmental concerns have led to look for alternative fuels of bio-origin sources such as vegetable oils, which can be produced from forests, vegetable oil crops, and oil bearing biomass materials. Vegetable oils have ener-gy content comparable to diesel fuel. The effect of neem oil and its methyl ester on a direct injected four stroke, single cylinder diesel engine combustion, per-formance and emission is investigated in this paper. The results show that at full load, peak cylinder pressure is higher for neem oil methyl ester; peak heat re-lease rate during the premixed combustion phase is lower for neat neem oil and neem oil methyl ester. Ignition delay is lower for neat neem oil and neem oil me-thyl ester when compared with diesel at full load. The combustion duration is higher for neat neem oil and neem oil methyl ester compared to diesel at all loads. The brake thermal efficiency is slightly lower for neem oil at all engine loads, but in the case of neem oil methyl ester slightly higher at full load. It has been observed that there is a reduction in NOx emission for neem oil and its me-thyl ester along with an increase in CO, HC, and smoke emissions