Physical and mathematical determination of the influence of input temperature changes on the molten steel flow characteristics in slab tundishes

Abstract

Transient fluid flow behavior in a tundish with two different arrangements, a bare tundish and a tundish using flow control devices, was studied using physical modeling and a mathematical model. The study places special emphasis on buoyancy effects, particularly transient buoyancy effects due to step change in inlet temperature. For the bare tundish case, the inertial forces are strongly dominant, while in the arrangement using flow control devices, tundish with turbulence inhibitor and low dams, the buoyancy forces are dominant. The results were compared to those representing the real behavior, considering temperature variations, for each tundish arrangement. This comparison made possible the determination of the probable implicit error that could be present in the estimation of the fluid flow characteristic behavior used for the design of the tundish geometry and flow control devices when the temperature variations are not considered.

Piv Method and Numerical Computation for Prediction of Liquid Steel Flow Structure in Tundish

“…For the non-isothermal conditions of steel flow through the tundish, the magnitudes of heat fluxes on particular tundish walls and bottom have been determined to be -2600 W/m 2 , whereas on the regulator walls -1750 W/m 2 . The losses on the free metal table surface are -15000 W/m 2 [9][10][11][12][13][14][15][16][17]. The wall condition with zero tangential stress was assumed on the free steel table surface.…”

Numerical Simulation of the Molten Steel Flow in the Tundish of CSC Machine / Symulacja Numeryczna Przepływu Ciekłej Stali W Kadzi Pośredniej Urządzenia COS

“…The equation of heat conductivity (1), the Navier-Stokes equations and continuity equation (2,3) are completed by the appropriate initial conditions and the classical boundary conditions [8][9][10][11][12][13][14][15] which are shown in Fig. 1.…”

“…The buoyancy forces developed by the fluid density change contribute to the modification of the steel flow patterns. Furthermore, the steel in the tundish also loses heat through the walls and the free surface [3]. Flow behaviour in the tundish is governed mainly by the size and shape of the vessel and the location of flow-control devices, such as dams, weirs, filters, striker pad, baffles with holes and turbulence inhibitors.…”

“…The two methods can be reproduced using a mathematical model and numerical simulations. Mathematical modelling was a very useful tool, since most of the cases are experimentally difficult to carry out [3,6,8,9].…”

Numerical and Experimental Analysis of Flow Phenomenon in Centrifugal Flow Tundish

“…5) And the calculation of plug volume follows the formula proposed in Ref. 6), where the plug flow is obtained when 1 % of the total injected tracer has left the tundish.…”