Numerical investigation of steady-state and transient operations of a turbocharged SI engine with electric supercharger

Gasoline engine downsizing, associated with turbocharging, has proved to be one of the most effective ways to reduce specific fuel consumption of the internal combustion engine. This tendency introduces a number of technical challenges, such as reduced steady-state low speed torque, delay in transient response caused by the turbocharger, combustion limitations due to propensity to knock. Advanced boosting systems can succeed in overcoming these issues; of particular interest is the solution featuring a second, electrically-driven, compressor in series with the turbocharger compressor. The engine considered in this work is a four-cylinder inline, turbocharged and electrically supercharged engine by FCA. In this work a 1D simulation of the mentioned engine is performed with and without the use of the electric supercharger in order to analyze its effect on steady-state and transient performance. The exploited software is GT-Power Version 7.4, by Gamma Technologies.