Optimization of Engine Performance and Emissions Using Ethanol-Fusel Oil Blends: A Response Surface Methodology

Abstract

This study evaluates the performance of a turbocharged spark ignition (SI) engine using a mixture of ethanol and fusel oil with gasoline (RON95) to assess engine performance, emissions, and combustion stability. This study utilizes Response Surface Methodology (RSM) to optimize the influence of engine speed, engine throttle, and fuel mixture on engine performance parameters, thermal efficiency, specific fuel consumption, and exhaust emissions. The experimental results show that COVimep (coefficient of variation of mean pressure in the cylinder) increases with adding ethanol and fusel oil proportions, with F30 showing the highest COVimep (2.80%). Optimization using RSM shows optimal conditions at an engine speed of 3000 rpm, 40% throttle, and F30 mixture, resulting in 33.0 kW of brake power, 35% thermal efficiency, 285.4 g/kWh of specific fuel consumption, and NOx, HC, and CO emissions of 1013.7 ppm, 185.3 ppm, and 1.59%, respectively. Validation experiments with the same conditions showed a brake power of 34.5 kW, thermal efficiency of 36%, and slightly increased emissions. The optimization results showed that RSM effectively optimises engine performance and emissions with a prediction error of less than 5% and can be applied to various fuel mixture combinations.