Study of The Concept of Diesel and Ethanol Dual-Fuel in a SIngle-Cylinder Research Engine

Abstract

This study examines the concept of dual-fuel combustion, and focuses in particular on the combination of diesel and ethanol in a compression ignition engine. Ethanol, as a renewable fuel source, plays a fundamental role in reducing dependence on fossil fuels and reducing greenhouse gas emissions. In the test setup ethanol is injected into the intake manifold (Port-Fuel Injection, PFI), while diesel is injected directly into the combustion chamber (Direct Injection, DI). The engine under investigation is a single-cylinder research engine designed to run on two fuels. In this configuration, diesel acts as the ignition fuel, which stimulates the ignition of the ethanol-air mixture. The aim of this study was to analyze the highest rate of substitution of diesel by ethanol while reducing engine load. In the method used the engine was first operated with diesel and ethanol. Subsequently, the ethanol injection was stopped, which led to a decrease in engine load. In order to correct the engine performance and achieve the same load again, the mass of the injected diesel had to be increased. This method has shown that it is possible to achieve the same workload with an ethanol fraction as with diesel alone.. In terms of thermodynamic and emission results, substituting a fraction of diesel with an equivalent amount of ethanol to achieve the same IMEP (Indicated Mean Effective Pressure) is a viable alternative. In addition the presence of ethanol was found to retard combustion compared to running on 100% diesel. The emission results show that dual-fuel operation keeps soot levels close to those achieved when running on diesel alone.