Abstract
Keywords:
diesel engine, turbocharging, transient operation, electric assisting systems, numerical simulation
Abstract
Turbocharged diesel engines are widely used propulsors due to their high power density and high efficiency. Majority of turbocharged diesel engines operate frequently in the transient operating regime. However, it is well known that turbocharged diesel engines suffer from an inadequate response to sudden load increase, which is a consequence of the nature of the energy exchange between the engine and the turbocharger. Influence of the direct energy supply with an integrated starter-generator-booster (ISG) mounted on the engine flywheel or the indirect energy supply with an electrically assisted turbocharger on the dynamic response improvement of the turbocharged diesel engine is investigated in this study. The use of realistic input parameters of electric motors and application of the experimentally verified computer simulation method ensures credibility of the presented results. The paper offers an analysis and extended parametric study of the interaction between a turbocharged diesel engine operating under various load conditions and electric assisting systems. It is evident from the presented results that electric assisting systems substantially improve load acceptance of turbocharged engine. Reductions in production and operating costs can therefore be achieved for the same requirements on engine performance due to the possible downsizing of the electrically assisted engines.