FINITE ELEMENT SIMULATION FOR THE OPTIMIZATION OF PARAMETERS IN CONTINUOUS CASTING OF SLABS

Abstract

The control of quality in continuous casting can not be achieved without the understanding of thermo-mechanical state (temperature, strain, and stresses) of slab due to variation in process parameters. The high computational cost of three-dimensional models sets a severe difficulty to use them for predicting cracking susceptibility of solidifying shell. The thermo-mechanical behaviour of a continuous casting slab has been simulated using a two dimensional mathematical model based on the considerations of fluid flow, heat transfer and solidification. The principal model equations are mass, momentum and heat balances. The steady state conditions are assumed. The different boundary conditions have been applied in various zones. A well known CFD software (FLUENT) has been chosen for the solution of the governing equations to predict the temperature distribution in the slab. This calculated temperature is used as input to ANSYS software for the analysis of stresses. For mechanical analysis, an elasto-plastic material model with bilinear isotropic hardening has been used. The model has been extended for the optimization of process parameters. The optimization strategy selects a set of cooling conditions and metallurgical criteria in order to achieve highest product quality. The results presented in this dissertation work show the thermo-mechanical behavior of slab under different operating and boundary conditions. Using the numerical model, the results can be produced for determining optimum settings of casting conditions for best strand surface temperature profile