A Study on the 2-Stage Turbocharging Strategy to Improve both Fuel Consumption and Exhaust Emissions

Abstract

Two different 2-stage turbocharging strategies, featured by the different low pressure turbine flow rate and controlling strategy of the air handling devices, were compared in order to improve the practical fuel consumption and the exhaust emissions in a heavy duty diesel engine. As the results, combination of the selected turbochargers that obtained a higher boost pressure in a broad engine speed and load range and the higher compression ratio can achieve simultaneous improvement in exhaust emissions and fuel consumption with actual driving conditions, i.e. mileage.