The effect of low reactivity fuels on the dual fuel mode compression ignition engine with exergy and soot analyses

摘要

In this study, the effect of fuel injection timing of diesel on the dual fuelled compression ignition engine with gasoline, methanol and toluene has been investigated. Closed cycle combustion simulations have been conducted to complement the experiment results and for a better understanding of the in-cylinder dynamics. Second law of thermodynamics analysis has been done for the designing of energy recovery devices. Exhaust soot particles has been analysed by scanning electron microscopy to get soot particle structure. Distributions of soot particle number by size and particle mass by size have been investigated. Experiments have been conducted for respective premixed ratios of gasoline/methanol/toluene at different start of injection (SOI) timing of diesel. Outcomes revealed that the maximum gross indicated thermal efficiency (GITE) of 39% is obtained for gasoline/ diesel mode. This mode shows 86% more oxides of nitrogen (NOx) in comparison with methanol/diesel mode at -25 crank angle degree (CAD) SCR case. About 54% more soot has been observed at -25 CAD SCR in toluene/diesel compared to that of gasoline/diesel mode. Maximum of 38.7% and minimum of 27.8% work exergies have been observed in gasoline/ and methanol/diesel modes respectively. Toluene/diesel mode shows the largest average primary particle diameter (D-p; 44 nm) among the dual fuel modes.