Throttling Effect on the Performance and Emissions of a Multi-Cylinder Gasoline Fuelled Spark Ignition Engine

The throttle mechanism, a regulatory technique of engine output, is accompanied by loss some energy. effect intake air throttling on the performance and emissions multi-cylinder spark ignition gasoline was experimentally investigated. coupled to hydraulic dynamometer equipped with customized cooling system for both dynamometer. Experimental tests were performed various speeds air-fuel ratios at WOT POT conditions optimized timing. acquired results recorded that better operation could be achieved in terms bmep, bsfc, ηb, CO, CO2 UHC compared POT. At same time, worst trend noticed NOx concentration due higher conversion efficiency fuel combustion. In speed conditions, operating 3000 rpm represents minima ϕ, CO UHC; maxima fluctuation sides this point. Maximum values ηb about 30.55% 28. 55%, while minimum bsfc 274 293 g/kW.h respectively. maximum bmep obtained 2500 940 kPa 904 kPa, 1525 977 ppm