A COMPARATIVE STUDY OF INTERFACE RECONSTRUCTION ALGORITHMS IN THE SIMULATION OF MOLD FILLING

摘要

Computational flow simulation and modeling is a recognized technique for prediction the filling of molds during the casting process. The mold filling commonly has gas-liquid interfaces. It means that this problem is free surface flow and we need to predict the gas-liquid interface. For implementing the free surface flow we used a Volume of Fluid (VOF) method. We applied two numerical schemes to improve the accuracy of the solution in the flow simulation of molten metal. One method is Piecewise Linear Interface Calculation (PLIC) method and the other is Donor-Acceptor (D-A) method. In the present work, we have tested simple problems (translations test and simple round-shaped model) to verify the module of the interface reconstruction algorithms. After validations, the accuracy and efficiency of these two methods have compared by simulating various real products. On the numerical simulation of free surface flow, it is possible for PLIC method to track very accurately the interface between phases. PLIC method, however, has the weak point where a lot of computational time hangs, though shows the more accurate interface reconstruction. Donor-Acceptor method has enough effectiveness in the macro observation of mold filling sequence though it shows an inferior accuracy, because computational time is short compared with PLIC method.