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In this paper, a recently improved Computational Fluid Dynamics (CFD) methodology for virtual prototyping of the heat treatment of cast aluminum parts, above most of cylinder heads of internal combustion engines (ICE), is presented. The comparison between measurement data and numerical results has been carried out to simulate the real time immersion quenching cooling process of realistic cylinder head structure using the commercial CFD code AVL FIRE®. The Eulerian multi-fluid modeling approach is used to handle the boiling flow and the heat transfer between the heated structure and the sub-cooled liquid. While for the fluid region governing equations are solved for each phase separately, only the energy equation is solved in the solid region. Heat transfer coefficients depend on the boiling regimes which are separated by the Leidenfrost temperature.

Direct injection of gasoline fuel has been gaining on applicability in recent years. Direct injection spark ignited engine has been one of the most investigated designs for achieving lower fuel consumption and for increasing the performance. Maintaining low emissions, decreasing fuel consumption and keeping driving performance are key challenges. Fuel injection quality is one of the most important factors, which directly affect general engine requirements like fuel mass flow, spray penetration and atomization for the combustion process. The multi-hole injector design is a very promising design type for application in direct fuel injection in automotive petrol engines. As a consequence of decreasing supplies of fossil fuels, mixing of different fuel components has become very common in recent years. The type of components which are to be mixed depends on local geographical fuel availability and motorization type.

This paper outlines an improved computational methodology to simulate the immersion quenching heat transfer characteristics. Main applicability of the presented method lays in virtual experimental investigation of the heat treatment of cast aluminum parts, above all cylinder heads of internal combustion engines. The boiling phase change process between the heated part and a sub-cooled liquid domain is handled by using the Eulerian multi-fluid modeling approach, which is implemented within the commercial Computational Fluid Dynamics (CFD) code AVL FIRE®. Solid and liquid domains are treated simultaneously. While for the fluid domain mass, momentum and energy equations are solved in the context of multi-fluid modeling approach, only the energy equation is solved to predict the thermal field in the solid region. For the presented quenching simulation, the solid and fluid parts are contained in a single domain.