Response Surface Methodology based Optimisation of Performance, Exhaust Emissions and Vibrations of a PFI SI Engine Operated in Dual Fuel Mode with E20 and GEM Blends

Abstract

The current study was carried out on dual-fuel diesel engines for optimising the performance, emission and vibration parameters with the help of response surface methodology. The engine was operated at 1800, 2200, 2600, 3000 and 3400 rpm by keeping the load 5 kg, with a combination of pure petrol, E20 and hydrogen at 3, 9, and 15 Lpm. Engine speed, various hydrogen flow rates and fuel blends are considered as input responses and brake thermal efficiency (BTE), brake-specific fuel consumption (BSFC), Nitrogen Oxides (NOx) emissions and vibrations are used as output responses. Optimisation of the engine was done by considering that BTE has to be in maximum condition and BSFC, NOx and vibrations to be in minimum condition. BTE and BSFC are high at 1832rpm speed with 15 Lpm hydrogen flow at blend 3, i.e., Gasoline-Ethanol-Methanol (GEM) blend. At 1832 rpm and a hydrogen flow of 15 Lpm with the GEM blend, the levels of NOx and vibrations were measured. E20 showed a rise of 12.35%, 8.69%, 22.22%, 12.76% and GEM blend showed a rise of 14.96%, 13.04%, 27.40% and 17.41% in BTE, BSFC, NOx and vibrations when compared to petrol at 15 Lpm hydrogen.