Enhancement of energy, exergy and soot characteristics with the utilization of MEK in diesel engine.

This study investigated the effects of methyl ethyl ketone (MEK) on a diesel engine's energy, exergy and emissions. The evaporation of a bi-component droplet of MEK and heptane was modeled. Furthermore, the soot morphology and nanostructure were quantified. Different blends were examined at other engine conditions. Running the engine under idle conditions and optimum speed considerably reduced engine emissions. MEK noticeably decreased the maximum reachable load of the diesel engine. Both specific fuel consumption and thermal efficiency increased with MEK. The exergetic efficiency increased while the fuel exergy decreased at the same work exergy. The effects of MEK on combustion characteristics were insignificant. However, a stronger premixed combustion phase was obtained where MEK evaporated first and caused a slightly longer droplet lifetime. Low percentages of MEK reduced CO emissions, while NOx emissions increased consistently with the MEK addition. The engine conditions noticeably influenced the unburned hydrocarbon emissions with MEK. Both smoke opacity and primary particle diameter decreased. The fringe analysis emphasized that MEK decreased fringe length, soot intensity, and alignment, increasing fringe tortuosity and spacing. Clearly, methyl ethyl ketone suppressed soot formation in a diesel engine and decreased its reactivity. [ABSTRACT FROM AUTHOR]