Abstract:
In this study, a direct injection compression ignition (DICI) engine was modified to utilize croton esters-diesel blends in equal ratio and at varied fuel injection pressures. The main aim of this research is tomake use of alternative fuels for diesel engines and
to reduce the emission of exhaust gases while minimizing the reduction of brake thermal efficiency associated with the low calorific value of bio-fuel.Theenginewas tested atvaried injection pressures of 220,240,260 and280 bar and at 0%,10%,20% and 30% exhaust gas recirculation (EGR) and the performance and emission characteristics of the modified engine were analyzed. The effect of higher injection pressures than the engine’s standard value of 220 bar and the varied EGR percentages on performance parameters such as brake thermal efficiency(BTE),brake specific fuelconsumption(BSFC)andexhaustgas temperature(EGT)werestudied.Athorough analysis on the effect of croton oil ester and diesel blends on smoke, CO, HC and CO2 emissions is also presented. The performance and emission characteristics were compared among the different injection pressures and exhaust recirculated gas percentages and the results show that brake thermal efficiency increases upto 240 bar before decreasing while the brake specific fuel consumption decreases and then increases at this injection pressure. It was observed that the use of EGR reduces the brake thermal efficiency except for 280 bar where 20% EGR enhanced the engine’s efficiency. The EGT and emission parameters were found to decrease at higher injection pressures.
