Tracking the filling front during polymer mold filling can be achieved by solving the so-called 'volume of fluid' (VOF) equation. In this paper, a method that unifies many of the existing VOF-based schemes is introduced. Each variant of this unified method requires, at each time step, the solution of a system of equations which can be nonlinear. The introduction of pseudo compressibility transforms the basic VOF equation into an equation that matches the well-known enthalpy formulation for solid/liquid phase change. This leads to a fully explicit scheme of the governing filling equations that does not require the solution of a system of equations. If the pseudo compressibility is small enough, the explicit solution is close to the solution obtained with a direct solution of the incompressible VOF equation. Further, in some cases, the explicit scheme is computationally efficient in terms of CPU time and accuracy. (C) 2000 Elsevier Science Inc. All rights reserved.
Bibliographical noteFunding Information:
This work has been partly supported by an NSF project on the product and process engineering for starch-based polymers, Grant DMI 97-00126. The authors also acknowledge the support of the Minnesota Supercomputer Institute and thank Profs. M. Bhattacharya and K. Stelson for their helpful discussions.
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