3D-CFD Simulation of Mixture Formation, Combustion and Heat Transfer Processes with AVL FIRE

Abstract

Based on selected examples the present status of 3D-CFD related to internal combustion engine applications is presented. The focus is on highlighting the current status of model validation and on demonstrating specific application methodologies using the CFD code AVL FIRE. From the broad area of diesel engine combustion system development, results of the analysis and optimization of mixture formation, combustion and pollutant formation are shown for conventional as well as alternative diesel combustion. The results quality related to the prediction of the in-cylinder pressure trace, heat release rate and pollutants is discussed in the context of related experimental data. In the field of gasoline engine development, the present possibilities related to 3D-CFD calculation of premixed flame propagation for the analysis and optimization of full load SI-engine combustion performance is presented. The applicability of the adopted models as well as their predictive capabilities are demonstrated based upon selected results of calculated flame propagation and knock onset characteristics and comparison of the results with related experimental data. Finally, the possibilities of 3D-CFD in the context of the analysis and optimization of the thermal loading of structural components are presented. The application of novel models for the calculation of the gas- and water-side heat transfer including coupled fluid / thermal calculations is demonstrated for the thermal analysis of the head-block compound of a passenger car SI-engine.