Effect of Early Injection Combined with EGR on Combustion Characteristics of Pongamia Biodiesel Blend

Abstract

Global warming and emissions from conventional fuels like diesel and petrol have resulted in a lot of interest towards the use of biofuels. This study focuses on CFD analysis of combustion in a direct injection CI engine fueled by Pongamia biodiesel blend PB20 (80% diesel and 20% Pongamia methyl ester). In order to achieve homogenous charge within the cylinder, the start of injection is advanced from the baseline configuration. Advancement of SOI requires a higher value of EGR in order to compensate NOx emissions. Performance and emission characteristics like ISFC, particulate matter and nitrous oxides have been studied by varying the start of injection timing combined with a fixed amount (50%) of EGR using CONVERGE™ simulation tool. Results have been validated and compared with the standard configuration. Advanced Injection helps in reducing soot which confirms homogenous mixing while the presence of EGR reduces NOx considerably. An optimum start of injection has also been recommended in the present study.