Effects of using ternary gasoline-ethanol-LPO blend on PFI engine performance and emissions

Abstract

To date, apart from alcohol, few alternative fuels have been investigated for the operation of port fuel injection (PFI) engines. The current study is examining the suitability of a ternary blend of lemon peel oil (LPO), ethanol, and gasoline as a drop in fuel for traditional gasoline engines. Unique combinations of LPO blends with a calorific value exceeding 40 MJ/kg and stoichiometric air to fuel ratio exceeding 14 are tested on a PFI equipped single-cylinder Kirloskar engine. In this study, two binary blends (G60L40, G80E20) and two ternary blends (G60E20L20, G40E20L40) are prepared on a volume basis and investigated for combustion, performance, and emission characteristics. Combustion stability based exhaust gas recirculation (EGR) rate of 10% is proposed for the ternary blend (G40E20L40). The experimental results showed that the thermodynamic performance of ternary blends is similar to baseline gasoline with a 60% reduction in CO and a 15% reduction in NOx with 10% EGR. Biofuel blends exhibit higher in-cylinder pressure than gasoline due to the higher laminar flame velocities of LPO and ethanol. The ternary G40E20L40 blend with 10% EGR at 3.91 bar BMEP produces higher brake thermal efficiency (BTE) and marginally higher brake specific fuel consumption (BSFC) indicating an insignificant effect on vehicle range on a full tank and good alternative that utilizes 60% renewable fuel with gasoline without any changes to the PFI engine and simultaneously reaping the benefits of significantly improved emissions.