Experimental assessment of power generation using a compression ignition engine fueled by farnesane – A renewable diesel from sugarcane

This work reports the experimental study of a single-cylinder compression ignition engine fueled with a renewable diesel from sugarcane called farnesane. The engine is representative of current small-scale power generation in very isolated rural areas existing in Brazil. A complete experimental assessment was made on engine combustion, performance, and pollutant emissions at 1800 rpm under different loads (from 4 to 7 bar IMEP). Results showed reduced values for the ignition delay, in-cylinder peak pressure and mean temperature when using farnesane compared to conventional diesel fuel, as well as lower heat release rate peaks at the premixed combustion phase and shorter diffusion combustion duration. Physicochemical properties differences, such as cetane number, H/C ratio and the biofuel paraffinic structure led to interesting emission behavior. Farnesane reduced NOx emissions by up to 34% (and further 48.6% using EGR), and particulate matter by up to 92%. Despite the higher in-cylinder peak pressure and greater fuel conversion efficiency for diesel fuel at the highest load, the biofuel exhibited gains of up to 3.3% in combustion efficiency and 5.9% in fuel conversion efficiency at intermediate and lower loads. Such improvements are closely related to the HC and CO levels depletion and the absence of aromatic compounds.