Hydrocarbon Speciation of Diesel Ignited Ethanol and Butanol Engines
Dual fuel applications of alcohol fuels such as ethanol or butanol through port injection with direct injection of diesel can be effective in reduction of NOx. However, these dual fuel applications are usually associated with an increase in the incomplete combustion products such as hydrocarbons (HC), carbon monoxide (CO), and hydrogen (H2) emissions. An analysis of these products of incomplete combustion and the resulting combustion efficiency penalty was made in the diesel ignited alcohol combustion modes. The effect of EGR application was evaluated using ethanol and butanol as the port injected fuel, with varying alcohol fractions at the mid-load condition (10 -12 bar IMEP). The impact of varying the engine load (5 bar to 19 bar IMEP) in the diesel ignited ethanol mode on the incomplete combustion products was also studied. Emission measurements were taken and the net fuel energy loss as a result of the incomplete combustion was estimated.