Process Modeling and Optimization: Issues and Challenges

We present a finite element method which is well suited for mold-filling and solidification problems. These problems present unusual challenges in physical modeling, numerical methods and the efficient use of computational resources. High Reynolds number, transient, turbulent flows with free surfaces must be modeled in complex 3D geometries. One or two equation turbulence models with wall functions are used. The position of the flow front in the mold cavity is computed using a pseudo-concentration technique. Computations are presented for free surface turbulent fluid flow coupled to heat transfer and phase-change. The methodology has the robustness and cost effectiveness needed to tackle complex industrial applications.

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