Modeling of Initial Mold Filling with Utilization of Swirl Blades

Abstract

The flow pattern in the uphill teeming process has been found to be closely related to the quality of ingots regarding the formation of non-metallic inclusions and entrapment of mold flux. The filling conditions can be improved by the utilization of a swirl blade in the runner. The emphasis of this study is to investigate the flow pattern of steel in the gating system and molds with swirl blades implemented at the bottom of the vertical runners during the initial stage of the mold filling process based on the authors' previous study. A two-mold gating system was adopted in the study and different orientations of the swirl blade were studied. In addition, same calculation method and boundary conditions were used to study the flow pattern in the uphill teeming. The results show that more calm filling conditions with less fluctuations are achieved in the molds with the implementation of swirl blades. However, a chaotic initial filling condition with a considerable amount of droplets is created when steel enters the molds. In addition, the orientation of the swirl blades affects the flow pattern of the steel. From the current results it is clear that a parallel placement of the swirl blade is better than a perpendicular placement of the swirl blade. Moreover, the fluctuations of the hump height decrease as the filling proceeds. In addition, the implementation of swirl blades can decrease and stabilize the wall shear stress value in the gating system.