Multi-response optimization of diesel engine operating parameters running with water-in-diesel emulsion fuel

Water-in-diesel emulsion fuel is a promising alternative diesel fuel, which has the potential to promote better performance and emission characteristics in an existing Diesel engine without engine modification and added cost. The key factor that has to be focused with the introduction of such fuel in existing Diesel engine is desired engine-operating conditions. The present study attempts to address the previous issue with two-phases of experiments. In the first phase, stable water-in-diesel emulsion fuels (5, 10, 15, and 20 water-in-diesel) are prepared and their stability period and physico-chemical properties are measured. In the second phase, experiments are conducted in a single cylinder, 4-stroke Diesel engine with pre-pared water-in-diesel emulsion fuel blends based on L16 orthogonal array suggested in Taguchi’s quality control concept to record the output responses (perormance and emission levels). Based on signal-to-noise ratio and grey relational analysis, optimal level of operating factors are determined to obtain better response and verified through confirmation experiments. A statistical analysis of variance is applied to measure the significance of individual operating parameters on overall engine performance. Results indicate that the emulsion fuel prepared by Sorbitan monolaurate surfactant at high stirrer speed endows with better emulsion stability and acceptable variation in physicochemical properties. Results of this study also reveal that the optimal parametric setting effectively improves the combustion, performance, and emission characteristics of Diesel engine