Co-combustion of biodiesel with oxygenated fuels in direct injection diesel engine

The paper presents results of experimental investigation of co-combustion process of biodiesel (B100) blended with oxygenated fuels with 20% in volume. As the alternative fuels ware used hydrated ethanol, methanol, 1-butanol and 2-propanol. It was investigated the influence of used blends on operating parameters of the test engine and exhaust emission (NOx, CO, THC, CO2). It is observed that used blends are characterized by different impact on engine output power and its efficiency. Using biodiesel/alcohol blend it is possible to improve engine efficiency with small drop in indicated mean effective pressure (IMEP). Due to combustion characteristic of biodiesel/alcohol obtained a slightly larger specific NOx emission. It was also observed some differences in combustion phases due to various values of latent heat of evaporation of used alcohols and various oxygen contents. Test results confirmed that the combustion process occurring in the diesel engine powered by blend takes place in a shorter time than in the typical diesel engine.