This work focused on an integrated approach of solutions to improve the combustion of Jatropha oil in an indirect injection Diesel engine (Lister type). The improvements were assessed using combustion parameters, especially cyclic dispersion. The Jatropha oil was preheated to 100°C and the Diesel engine has received changes in fuel injection timing and injection pressure variation. The overall engine performance (specific fuel consumption, thermal efficiency and exhaust gas temperatures), cyclic dispersion, ignition delays obtained with Jatropha oil and Diesel fuel were compared. The results show that for the performance, the injection timing of 20 Crank Angle (CA) Before Top Dead Center (BTDC) and the injection pressure of 170 bars are the settings adapted for both fuels to the different engine loads. The results also show that cyclic dispersion could be used as a very good tool for assessment of adequate operating conditions of this type of engine, even at low loads. The cyclic dispersion is low with coefficients of variation of the indicated mean effective pressure (COVIMEP) whose values are less than 10%. The lowest values of the COVIMEP are obtained when the injection settings are 20 CA BTDC and 170 bars.

Jatropha Oil, Diesel Engine, Injection Timing, Injection Pressure, Cyclic Dispersion