Abstract
	Numerical simulation is widely used and accepted in manufacturing as a way to improve the quality of products and to optimize the manufacturing processes. The foundry industry is increasingly using computer simulation with a view to improve casting design and quality objectives. The castability can be assessed via simulation in an attempt to ensure controlled mold-filling behavior and progressive solidification toward feeders. The simulation permits to visualize the filling dynamics and to characterize the thermal field, the cooling stage, shrinkage as well as to control the process by varying the operational parameters. The aim of the first part of this paper is to present the theoretical basis for the development of a numerical model for simulation of mold-filling and solidification of a binary alloy. For the mold filling process, turbulence models in addition to the Fractional Volume (Volume of Fluid - VOF) algorithm is used to model the computational fluid dynamics (CFD). The approach allows one to handle, with at least second order accuracy, the continuously moving boundary between the injected fluid and the air that initially is in the mold cavity. The liquid metal assumes Newtonian fluid and incompressible fluid conditions. For the solidification process, the mathematical formulation of heat transfer is based on the general equation of unsteady state heat conduction. Three forms of latent heat release during solidification are presented: linear, exponential and sinusoid behavior as a function of the solid fraction.