Abstract
In order to manage increasingly complex combustion engines and to compensate the high costs of calibration work, a simulation environment for optimal parametrization of the engine management system is required. The aim of this study is to establish a coupled modeling approach, which interfaces models of the engine control and the vehicle powertrain with a detailed thermodynamic model of the combustion engine. A functional model of the electronic control unit is built with a modular architecture including all relevant modules. As fuel consumption specifications are often referred to a driving cycle, the dynamics of the powertrain and the vehicle are considered in a mechanical model. Linking these models with a detailed combustion engine simulation opens up the possibility to support the development and calibration of future engines, demonstrated here for a turbo-charged DISI engine with a fully-variable valvetrain. Thermodynamic processes are implemented within a 1D gas exchange model which allows to consider not only steady-state but also transient engine operation. The successful validation of this complex coupling technique is presented with exemplary results from all stages of the validation process. Finally, the advantage of this simulation methodology is shown by a detailed thermodynamic analysis of a dynamical driving sequence demonstrating the attained capabilities.
KEYWORDS – simulation, driving cycle, fuel consumption, virtual calibration, 0D/1D engine modeling