Multi response optimization for the management of nox smoke performance trade off in a di diesel engine fuelled with diesel oxygenate blends

Abstract

Diesel engines do not have the luxury of combusting a thoroughly premixed charge inside the combustion chamber like gasoline engines Apart from the inherent trade off relationship between NOx and smoke emissions any attempt to reduce emissions also affected engine performance From the literature reviewed it was inferred that the better management of fuel injection timing fuel injection pressure intake oxygen concentration and diesel reformulation with oxygenates could balance the trade off between emissions and performance In such problems with multiple objectives Design of Experiments DOE with mathematical modelling and multi response optimization approach could be advantageous This study employed oxygenates derived from lingo cellulosic biomass feedstock for diesel reformulation There is an attractive opportunity for commissioning bio refineries in rural areas of India to process the abundant lingo cellulosic biomass available from the vast fertile lands and produce value added bio fuels for powering stationary diesel engines meant for irrigation and rural electrification In this context three oxygenates viz iso butanol n pentanol and dimethyl carbonate DMC derived from lingo cellulosic biomass feedstock were used This study presents a multi response optimization approach that could best utilize the oxygenates for partially replacing diesel and for reducing both NOx and smoke simultaneously with best possible performance A standard engine fuelled with diesel injected at standard injection timing of 23 CA bTDC and standard injection pressure of 210bar with no EGR is used as a reference newline