MOLD FILLING SIMULATION BASED ON THE BODY FITTED COORDINATE SYSTEM IN AN UNSTRUCTURED GRID SYSTEM

摘要

A new numerical method based on the body fitted coordinate (BFC) and the unstructured grid system has been developed using the SIMPLE scheme coupled with modified VOF algorithm. The former has been known as an effective method for incompressible fluid flows and the latter as a useful model for tracking of free surface respectively. Especially, the body fitted coordinate system, known as the most powerful method to predict the fluid flows around the complex mold wall of high curvature, such as thin-walled and arbitrary curved shapes, was also adopted. The newly-defined coordinate system was used in order to adopt the unstructured grid system to overcome the difficulties of the structured BFC grid generation. Several test cases on the mold filling problems were simulated to verify the present unstructured SIMPLE-BFC-VOF method, and compared with both experimental results and other numerical models. It is concluded that the present algorithm can show the prominence of the SIMPLE-BFC-VOF in fluid flow analysis and mold filling of castings, and serve the convenience of the unstructured grid generation.