Research On Temperature Prediction Model Of Molten Steel In Lf

With the progress of the clean steel smelting technique and the development of continuous casting, the technology of secondary refining has a rapid popularization. As a kind of secondary refining equipment, LF (Ladle Furnace) which has excellent synthesized functions is widely applied on the steelmaking process.The temperature of molten steel is one of the most universal and important technical parameters during LF refining process, it is important to control the molten steel temperature of LF for the quality of steel and the operation of continuous casting, and the accurate forecasting of molten steel in LF is an important precondition for controlling temperature of molten steel and the base to realize the automatic control by computer. However, with the high temperature of molten steel and the bad condition under which the temperature is measured, it is difficult to get the accurate numerical results of the molten steel temperature. In a word, there is important practical meaning to predict the molten steel temperature of LF.On the basis of energy-balance principle with theoretical analysis, a mathematical model used for forecasting molten steel temperature after measuring the temperature of molten steel for the first time during LF refining process is established in this paper. The heat transfer in ladle refractories (including side and bottom) is described with non-steady differential equations under one-dimension cylindrical coordinates and rectangular coordinates.In order to improve the accuracy of the thermophsical parameter identification, the genetic algorithm is applied. With the results of the parameter identification, a complete temperature prediction model of molten steel in LF is presented.The computer simulation results show that the steel temperature predicted by this model is in good agreement with the real measured data. It means that the model can be used to describe the heat transfer behavior in LF process, and it can be applied for steel temperature automatic control program during the LF refining process. Furthermore, the on-line tuning of the temperature prediction model of molten steel in LF is implemented, so that the model could be used accurately under different conditions.