Determination of optimal combustion conditions in a diesel engine operating on ethanol/diesel mixtures.

This study aims to determine the optimum ethanol/diesel mixture ratio, boost pressure, and cycle duration for providing the maximum engine performance and the minimum exhaust emission levels in a diesel engine. The statistical analyses were performed using the L 32 orthogonal array of the Taguchi. According to the calculated S/N ratios, it was revealed that there was almost a linear relationship between an increase in boost pressure and the selected engine output values. Similarly, a direct relationship was observed between the increasing alcohol content of the blend and the emissions of CO, CH 4 and NO x. The analysis of variance (ANOVA) technique was utilized to investigate the contribution of the levels of control parameters on experimental variables. In all ANOVA analyses, R² was 90% and above for all variables, while the goodness of fit was calculated to be at the lowest level in NH 3 emission. According to ANOVA analysis results, it was seen that the boost pressure has a substantial impact on CO 2 emission formation. The cycle duration has a dominant effect on cylinder gas pressure, thermal efficiency, fuel consumption and NO x emission. In contrast, the blend ratio considerably affects combustion noise, CO, CH 4 , and NH 3 emissions. Mainly, improvements were observed in exhaust emission levels, excluding ammonia emissions, with the increase of boost pressure and blend type. • The orthogonal array L 32 of the Taguchi method was utilized to determine the optimum combination. • In the established model, each output parameter R² was calculated to be 90% and above. • Cycle duration significantly affects the maximum cylinder gas pressure and NO x emissions. • Alcohol content in diesel fuel significantly affects combustion noise, CO, CH 4 , and NH 3. • Boost pressure has a significant impact on CO 2 emissions. [ABSTRACT FROM AUTHOR]