INVESTIGATION OF TUNDISH AND MOLD INTERMIXING USING PARAMETRIC APPROACH

Abstract

Numerical investigations inside tundish with and without mold have been carried out by solving the Navier Stokes equation together with standard k-c turbulence model. The residence time distribution (RTD) curves have been used to analyze the fluid flow behavior inside the tundish. Intermixing phenomenon in a six strand billet caster having T-shape tundish is numerically investigated for grade change process in chapter 4. T-shape tundish results from experimental investigation were found to match very closely with the numerically obtained results for a full scale tundish. Mixing phenomena has been studied by numerically solving the species concentration equation in a boundary fitted coordinate system comprising the geometry of the tundish. The solution of the species concentration equation has been utilized to compute intermixing amount in different shapes the tundish. Comparative study has been done to analyze the intermixing amount and flow behavior inside different shapes of tundish. Study shows that shape of tundish play significant role on intermixing amount. Velocity vectors analysis also done for boat shape, T-shape and V-shape tundish. It has found that the intermixed amount is minimum in mold attached to billet caster with different shapes of tundish. In chapter 5, we study the effect of flow modifier inside the boat shape tundish. In this work there is an optimum height of the dam exists between the two heights for which the intermixing amount is least. The position of dam is near the inlet symmetry plane has minimum intermixed amount. The intermixing amount for the tundish with baffle is less as compared to the bare tundish and other modifier used in this work. So the flow control devices help to increase the quality of the final product by reducing the intermixing amount. In chapter 6, we study the effect of port angle inclination on submerged entry nozzle on the flow pattern and thermal contour inside the slab mold. It also affects the intermixing amount in the slab mold. 45 degree pot angle inclination has low intermixed amount in the slab mold