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

摘要

In order to obtain a higher resolution of the free surface configuration, an adaptive grid refinement technique is incorporated into the volume of fluid (VOF) and the marker surface methods for three-dimensional finite element analysis of the filling stage in the die-casting process. The adaptive grid 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 those of the internal and external regions are distributed over the surface region. The adaptive grid is used for generating the fluid region grid that better 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 benchmark problem of the conference on the "Modeling of Casting, Welding and Advanced Solidification Processes VII" (MCWASP VII) has been analyzed and the numerical results are found to be in good agreement with the experimental results. A typical industrial problem of the die-casting process such as a cover of transmission case has been analyzed and it has been shown that the adaptive grid incorporated into the VOF and marker surface methods can be effectively applied to general die-casting process analysis.