Notable reductions in blow-by and particle emissions during cold and hot start operations from a turbocharged diesel engine using oxygenated fuels

The present study explores a comprehensive investigation of diesel blow-by, particulate matter (PM), particulate number (PN) and nitrogen oxides (NOx) emissions for cold and hot start operations in a six-cylinder, turbocharged diesel engine. A wide range of oxygenated blends of fuel-bound oxygen ranging from ~4% to ~8% (wt%) was used in the study. A reference diesel was also used for the comparison of the emissions results with those of oxygenated blends. Waste cooking biodiesel and an oxygenate, diethylene glycol dimethyl ether (diglyme) having three times higher cetane number than diesel and high fuel-bound oxygen, was used to make the oxygenated blends for examining the effect of fuel oxygen on diesel blow-by, PM, PN and NOx emissions. Carbon monoxide (CO), total unburned hydrocarbon (THC) and carbon dioxide (CO2) emissions were not targeted in this investigation. Fuel energy rate, exergy rate and exergetic cost were also investigated in this study. The experimental results show, blow-by, both PM and PN emissions were reduced significantly with a penalty of NOx emissions with oxygenated blends compared to diesel fuel during both cold and hot start operations. The energy rate, exergy rate and exergetic cost with oxygenated blends reveal insignificant variations relative to diesel.