Application of an adaptive grid refinement technique to three-dimensional finite element analysis of the filling stage in the die-casting process

In order to obtain a higher resolution of the free surface configuration, a n adaptive grid refinement technique is incorporated into the volume of flu id (VOF) and the marker surface methods for three-dimensional finite elemen t analysis of the filling stage in the die-casting process. The adaptive gr id is created at each time step through the grid refinement and coarsening procedures, as opposed to employing the fixed grid in the classical VOF and marker particle methods. In the adaptive grid, the elements finer than tho se of the internal and external regions are distributed over the surface re gion. The adaptive grid is used for generating the fluid region grid that b etter describes the shape of the predicted free surface at each time step, and for advancing the predicted free surface more precisely. To verify the efficiency of the adaptive grid refinement technique rigorously, a benchmar k problem of the conference on the "Modeling of Casting, Welding and Advanc ed Solidification processes VII" (MCWASP VII) has been analyzed and the num erical results are found to be in good agreement with the experimental resu lts. A typical industrial problem of the die-casting process such as a cove r of transmission case has been analyzed and it has been shown that the ada ptive grid incorporated into the VOF and marker surface methods can be effe ctively applied to general die-casting process analysis. (C) 2001 Elsevier Science B.V. All rights reserved.