CFD modeling of Fast Turbulent mixing process of Ethanol in Homogeneous Charge Compression Ignition Engine with the application of Exhaust Gas Recirculatio

Abstract

The importance of design the type of internal combustion engines such as Homogenous Charge Compression Ignition (HCCI) which increase efficiency while decreasing harmful emissions with low fuel consumption is steadily increasing. HCCI is a combustion concept, which is a hybrid between Otto engine and Diesel engine, which is thermodynamically favorable, leading to the benefit of high thermal efficiency. The geometry setup for HCCI engine is drawn and mesh size is fixed for appropriate simulation setting using ANSYS 17.2 software for analyses. In this investigation, port fuel injection method is used for the homogeneous mixture preparation and injection for HCCI mode. The research is aimed to develop the CFD modelling of fast turbulent mixing processes of ethanol in HCCI engine conditions through air-fuel mixture preparation with application of exhaust gas recirculation under various engine factors. The HCCI combustion is successfully achieved. Combustion simulations are performed by ANSYS 17.2 software for combustion and emission behavior of ethanol HCCI engine. It is found that combustion starts at intake charge temperature of 720K. Combustion behavior investigation is carried out on addition of 0% to 30% EGR to show the alternative use of ethanol instead of conventional fuels. It is found that The Turbulent kinetic energy is increased by addition of EGR which will facilitate rapid combustion in the combustion chamber to increase engine’s efficiency and fast mixing of ethanol and air for homogeneous mixture is obtained which, in turn leads the engine to 40% minimized pollution, 20% decreased fuel consumption rate and 15% increased the engine efficiency. The result obtained has been validated with experimental and theoretical research work.