Prediction of Gas Hole by Mold-Filling Simulation with Consideration of Surface Tension

Abstract

The algorithm for mold-filling simulation with consideration of surface tension has been developed based on the CIP method. As a test problem, a squeeze casting simulation was taken up. As an application to a practical casting problem, we also applied this scheme to a die-casting simulation and compared the numerical results with the experimental data on the size and the position of blow holes. Numerical results both with and without surface tension indicated the existence of blow holes. However, the simulation without surface tension tended to underestimate the size of blow holes. Through these numerical results, it is confirmed that the consideration of surface tension is very important for predicting the size and the position of gas trapped in mold cavities. Furthermore, we propose a criterion for estimating whether the gas remaining in the cavity is compressed or expanded during mold filling, and adopt it to a practical die-casting problem.