The effect of alcohol fumigation on diesel engine performance and emissions

The effects of ethanol fumigation (i.e. the addition of ethanol to the inta ke air manifold) and ethanol-diesel fuel blends on the performance and emis sions of a single cylinder diesel engine have been investigated experimenta lly and compared. An attempt was made to determine the optimum percentage o f ethanol that gives lower emissions and better performance at the same tim e. This was done by using a simple fumigation technique. The results show t hat both the fumigation and blends methods have the same behavior in affect ing performance and emissions, but the improvement in using the fumigation method was better than when using blends. The optimum percentage for ethano l fumigation is 20%. This percentage produces an increase of 7.5% in brake thermal efficiency, 55% in CO emissions, 36% in HC emissions and reduction of 51% in soot mass concentration. The optimum percentage for ethanol-diese l fuel blends is 15%. This produces an increase of 3.6% in brake thermal ef ficiency, 43.3% in CO emissions, 34% in HC and a reduction of 32% in soot m ass concentration. (C) 1999 Elsevier Science Ltd. All rights reserved.