SIMULATION OF THE STEEL LADLE PREHEATING PROCESS

CFD simulation of a steel ladle preheating process was performed with several goals. One was to estimate the impact of process parameters on the preheating. Further the final lining temperature and the temperature distribution in dependence of the process parameters are of interest as they influence the thermal shock during filling of the ladle. The considered steel ladle is preheated up to temperature of 700-800 degrees C by natural gas firing before it is transferred to the steel plant and finally heated to operation temperature. In the model, both hot gas and refractory are simulated. The calculations were executed with ANSYS Fluent software. For the gas combustion a non-premixed combustion approach including a laminar flamelet concept was applied. The radiation was calculated with a discrete ordinates model, the turbulence with a realizable k-epsilon model. As a result, velocity field, temperature and composition of the gas were calculated. The model includes also the heat transfer between flue gas and refractory, which is calculated depending on temperature and flow conditions. Further simulations including parameter studies and optimization of the process with the aim to reduce energy consumption are intended. The achieved results can support the thermo-mechanical modeling of the refractory lining, especially under the conditions of the following thermal shock, as well as the investigation of carbon burnout in magnesia-carbon refractories during preheating.