An experimental investigation of injection timings and injection pressures on a compression ignition engine fueled with hybrid fuel‐1 derived from waste cooking oil

Abstract

AbstractIn recent years, hybrid fuels have gained more popularity as a substitute fuel for petro‐diesel over biodiesel, due to their comparable properties, renewable nature, and easy processing. The main objective of this study is to experimentally investigate the combined effect of injection timings (ITs) (21, 23, and 25° before top dead center [BTDC]) and injection pressures (IPs) (200, 250, and 300 bar) on the engine characteristics of a compression ignition (CI) engine fueled with hybrid fuel (HB‐1). The hybrid fuel was prepared by mixing waste cooking oil, ethanol, and n‐butanol in appropriate proportion, that is, 69:18:13 by vol %, respectively. The experimentation was carried out on a single‐cylinder CI engine having rated power of 3.5 kW, four‐stroke, eddy current loading, water‐cooled, and run at constant speed of 1500 rpm. The experimental results were obtained at 80% of full load for combustion, performance, and emission characteristics of hybrid fuel and comparison have made with original setting (IT‐23 BTDC and IP‐200 bar). The obtained results showed that advancement in IT leads to higher cylinder pressure and heat release peaks, whereas retardation leads to opposite trend as compared to the original setting. Moreover, at IT‐25° BTDC with IP‐300 bar, higher brake thermal efficiency was measured than all the altering parameters, whereas brake specific energy consumption and exhaust gas temperature were found to be increased slightly in all altering parameters as compared to original setting. The Carbon monoxide and unburnt hydrocarbon emissions increased with all the altering parameters as compared to original setting. The advancement in IT with IP‐200 bar produced higher oxides of nitrogen (NOX) level than all other altering parameters, while other ITs and IPs emitted lower NOX level as compared to original setting. The IT‐25° BTDC with IP‐200 bar produced lowest smoke opacity as compared to other altering parameters.