A numerical model for mold filling based on a body-fitted coordinate system

A new model has been developed for the simulation of mold filling in thin-walled and curved-shape mold cavities. In the present method, the SIMPLE scheme was adopted to solve the momentum transport and the VOF (Volume of Fluid) method to trace the free surface in mold filling processes. In order to improve the solution accuracy in modeling mold filling in thin-walled and curved-shape mold cavities, the body-fitted-coordinate (BFC) concept, which was known as the most effective method to predict a flow field in a curved-shape cavity, was adopted. The governing equations for fluid flow and heat transfer were transformed based on the BFC concept. The non-staggered mesh and the momentum interpolation method were used which are essential for the BFC method. In addition, the standard VOF method was modified for the treatment of a free surface based on the BFC concept. The standard DAFA (donor and acceptor flux approximation) method was also revised as a suitable form. Several examples on mold filling problems having curved-shape mold cavities were simulated and the results were compared with other simulation methods. It is concluded that the present SIMPLE-BFC-VOF method can be used as an effective simulation method for the simulation of mold filling in thin-walled and curved-shape mold cavities.