Impact of varying injection pressure on CI engine characteristics fuelled with Ceiba pentandra biodiesel and NOx reduction strategy

The novelty of the present work deals with the experimental investigation on the effects of varying injection pressure (IP) on CI engine characteristics using a novel Ceiba pentandra biodiesel at 20% by volume (B20). The key objective of this study is to enhance the engine characteristics by increasing the IP of the fuel blends without any major engine modifications This strategy could improve the performance of the engine as higher IP resulted in improved atomization and better air-fuel mixing. From the experimentation it was found that combined strategy of biodiesel blend (B20) and higher IP (260 bar) resulted in increased BTE (9%), CP (8.5%), HRR (2%) and reduced BSFC (9%), CO (14%), HC (16%), and Smoke (16%) than diesel (B0) at a standard IP of 200 bar. To overcome the challenges of higher NOx emission at higher IP, exhaust gas recirculation (EGR) technique is also implemented at lower rates. With the effect of 15% EGR, there was a subsequent 29% reduction in NOx emission achieved without affecting other emissions trade-offs.