LAUSR

Abstract The electric supercharger has the advantages of reducing turbo lag and improving low-speed torque of turbocharged engine. The steady-state model using 1D simulation was performed to analyze the effect of the supercharger on the increase of BMEP and the combustion phenomena. Also, transient simulation using a mean value engine model (MVEM) was performed to analyze the improvement of engine response and fuel economy. The differences of engine performance were analyzed according to three locations (Layout A, B, and C) of the supercharger and the air-fuel ratio under controlled and uncontrolled conditions. The BMEPs increased 140.3%, 65.6%, and 17.3%, based on the maximum BMEP of the engine under the air-fuel ratio controlled condition in 1000 rpm, 1250 rpm, and 1500 rpm respectively. The validity of the BMEP analysis can be verified through the results of the combustion pressure; the results seem reasonable in this respect. The volumetric efficiency, maximum combustion temperature, and intake mass flow rate were compared to analyze the cause of volumetric efficiency change by using the supercharger and air-fuel ratio control. In addition, the total fuel consumption decreased by 18 g from 574 g to 556 g owing to the effect of the supercharger in the NEDC simulation.