THE EFFECT OF DIESEL-ALCOHOL BLENDS ON THE COLD-START COMBUSTION OF A COMPRESSION IGNITION ENGINE

Abstract

The present work represents an experimental investigation of the effect of blending diesel fuel by alcohol on the cold-start combustion characteristics of the compression ignition engine. The studied characteristics are the CO2, CO, and HC concentrations in the exhaust gases, in addition to the mixture Air/Fuel ratio, exhaust temperature, and engine noise levels. The experimental work has been carried out using a 4-stroke, single-cylinder compression ignition engine at different blending ratio values. These values are 0%, 10%, 20%, and 30% by volume of alcohol concentration with respect to the total mixture concentration. The engine has been tested under two rotational speeds (1800 and 2000 r.p.m). Two alcohols have been used in the experiments, these are ethanol and methanol. The obtained results showed that blending diesel fuel by alcohol has a positive effect on engine exhaust results during the cold-starting period. And that the results obtained from the ethanol blends are better than those obtained from the corresponding methanol blends. It is shown also that the 10% blending ratio for both ethanol and methanol blends is almost the optimum blending ratio, according to the results.