Application of catalytic converter SI engines, vhivh are fuelled by gasoline and LPG, and its effects to engine performance and exhaust emissions

Ill APPLICATION OF CATALYTIC CONVERTER TO SI ENGINES, WHICH ARE FUELLED BY GASOLINE AND LPG, AND ITS EFFECTS TO ENGINE PERFORMANCE AND EXHAUST EMISSIONS (M.Sc. Thesis) Nureddin DİNLER GAZI UNIVERSITY INSTITUTE OF SCIENCE AND TECHNOLOGY December 2000 ABSTRACT In this study, applications of alternative fuel (LPG) and catalytic converter, spark ignition engines emission-reducing solutions, were investigated. Experimental studies were conducted on a 4-cylinder, 4-stroke, Ford brand spark ignition engine. First, the engines converted to be fuelled with LPG and at different spark timing values, engine performance and exhaust emissions behavior were characterized. After the catalytic converter was mounted on the exhaust system, experiments were done for LPG and unleaded gasoline. Effects of catalytic converter on engine performance and exhaust emissions were characterized and compared with each other. Experiments to characterize the performance of engine were performed on engine at wide-open throttle position. Engine speed was changed with loading by hydraulic dynamometer.IV Experiments to characterize the behavior of exhaust emissions were performed on engine at steady speed (2400 rpm) and engine load was changed between 0% - 100% load. Experiments were performed for unleaded gasoline and LPG at for different spark timing values. The engine operation with LPG, torque and brake power is less than the engine operation with unleaded gasoline. After the installation of catalytic converter on exhaust system, a decrease about 5 % was measured in torque and brake power. There was an increase in brake specific fuel consumption about 5-10 %, and decrease in brake efficiency. After the catalytic converter CO, HC emissions were reduced effectively; but NOx emissions could not be converted efficiently because of the absence of closed loop catalytic converter system. Furthermore, conversion efficiency of catalytic converter was determined. Results were presented as graphics. Science Code : 625.05.03 Keywords : LPG, Catalytic converter, Internal combustion engine Page Number : 123 Adviser : Prof. Dr. Nuri YÜCEL