Emission reduction in a DI diesel engine using exhaust gas recirculation (EGR) of palm biodiesel blended with TiO2 nano additives

Recent developments in nano additives focuses on lowering the diesel engine exhaust emissions. While the usage of biodiesel in diesel engine at lower blend percentage (10%-30%) with mineral diesel can be well utilized without any engine modifications, the main striking factor in biodiesel application in diesel engine is higher NOx formation due to excess in-built O-2, which could be overcome with the usage of EGR (exhaust gas recirculation). However, EGR usage raises the concerns of HC, CO and smoke emissions. Overcoming the above existing problem, the current research proposal focuses on EGR of B30 (30% palm biodiesel-70%diesel) blended with 25 ppm TiO2 nanoparticles (PBN). Experimental test results obtained for PBN-EGR were outstanding than the conventional PB-EGR system since there is a noticeable drop in BSFC, HC and CO emissions with increase in EGT (exhaust gas temperature) than PBN. NOx emissions of PBN-EGR were on par with PB-EGR throughout the load. At higher engine loads, smoke emitted by PBN-EGR were lower than PB-EGR. With increase in EGR percentage in PBN, cylinder pressure was only marginally lower and heat release rate was higher than PBN. The present investigation enumerates that the synergic effect of nanoparticle, biodiesel and EGR is effective in improving the performance with minimized exhaust emissions. (C) 2019 Elsevier Ltd. All rights reserved.