The Development of a Mathematical Model to Predict Composition Distribution in Casting Slab and Intermix Slab Length during Ladle Changeover Period and Its Verification by Physical Model

Abstract

It is desirable to be capable of determining the composition distribution in casting slab and the intermix slab length during the ladle changeover period of the continuous casting operation. A 3-D mathematical model has been developed based on the SOLA-SURF technique and the K-ε two equations turbulence model to simulate the fluid flow and mass transport phenomena in tundishes during this period, which in turn determines the composition distribution in the casting slab. The free surface which varies during the ladle change over period was treated by a kinematic equation of height function rather than assuming it to be constant and flat. The model was designed to be executable on an IBM compatible 386 or 486 personal computer. An irregular mesh system was also employed to handle the actual dimensions of the ladle nozzle, tundish, and submerged nozzle to the casting mold. The mathematical model was then verified with the measurement data obtained from a full scale water model. The comparison results are rather satisfactory. It is shown from this study that the quantity of the residual fluid in the tundish when ladle changeover occurs affects the composition distribution in the transitional slab and thus the intermix slab length. © 1993, The Iron and Steel Institute of Japan. All rights reserved.