The effect of diesel/ethanol blends on variations of selected combustion parameter

This paper presents and discusses selected research results of the diesel engine fuelled with blends of: diesel oil (DO), synthetic ethanol (ET) as oxygenated additive and small quantity of fatty acid methyl esters (FAME) used as emulsifier. Content of ethanol in diesel oil was changed in wide range (up to 50%). Addition of 5% by vol. Of FAME was constant for each tested mixture. Preliminary tests were focused on influence of fuels blends composition on its combustion process. The main analyzed parameter was mean indicated pressure and its unrepeatability index. Research suggests that diesel oil blended with up to 20% of ethanol can be successfully used for diesel engines feeding. Higher ethanol content in mixture with diesel oil is unfavourable because misfire phenomenon occurs immediately. In this case tested engine works unstable with extremely high toxic gases emission. Some physical properties of tested fuels, measurement system configuration, Values of mean indicated pressure vs. cycle number for AD3.152 engine fuelled with: pure diesel oil, ETIO, ET20, ET30, ET 40, ET50, Variations of unrepeatability index of mean indicated pressure in relationship to kind of tested fuels are presented In the paper. Research shows that tested engine is not possible to operate with using above 40% of ethanol content in diesel oil, as the fuel simply will not ignite.