Influence of Fuel System Variations on Performance and Emission Characteristics of Combined Air-Wall Guided Mode Modified GDI engine with Alcoholic Fuels and Exhaust Gas Recirculation
Abstract GDI engines commercially existed with spray guided mode where the fuel injector placed almost vertically and sprayed fuel is occupied throughout the volume of combustion chamber. With the advanced emission norms, NOx and Soot emissions control is the major task along with lower fuel consumption. To achieve the advanced emission norms, further modifications are required before or during combustion. Combined air-wall guided mode combustion chamber modification is the advanced stage required for further improvement in mixing and superior combustion. Air-wall combined mode involved piston crown shape modification so that the modified shape should impart turbulence effects and divert the fuel/mixture flow towards the spark plug tip to initiate the combustion process. In this study, the combined air-wall guided mode gasoline direct injection engine was tested with gasoline blends using Ethanol, Methanol and N-Butanol at 20, 35 and 50% proportions under specific fixed conditions: 1500 rpm speed, 10% EGR and FIP of 150 bars with three split injections at 320˚, 220˚ and 100˚ before TDC. Tests were conducted over these gasoline blend proportions for engine performance and emission characteristics and achieved beneficial results with E20 gasoline blend over the entire applied torque values.