Abstract
This work is intended to promote the understanding of the different phenomenological combustion models and to assure the transfer of these models for new engine generations. In order to estimate in a predictive way influences on the spark-ignited combustion, on its emissions and on combustion anomalies, the research field of phenomenological combustion modelling becomes more and more important. Due to new engine technologies (e.g. turbo-charged SI-engines with direct injection), it is often not appropriate to simply apply combustion models developed more than 30 years ago for the current generation of engines. Different models, e.g. the entrainment combustion model, are first compared theoretically to enhance their understanding and then extended to improve their applicability.
For the application of a combustion model on engine maps of operating points within an engine process simulation, thermodynamic engine measurements as well as a study of the flow field using 3D-CFD simulations and a study of the flame propagation using optical measurements are carried out. The influence of tumble on the turbulent kinetic energy in the combustion chamber is approximated in an extension of the utilized turbulence model. Additionally, a new formulation for the turbulent flame speed is applied.
Keywords: phenomenological, combustion, simulation, turbulence, tumble