| Based on the converter dimension of different service lives in the Chongqing Iron and Steel Co. Ltd, according to the similarity theory, a combined blowing converter model and top (bottom) lance isothermal analog model are designed as the scale of 1:8. the non-isothermal flow caused by temperature lifting induced expansion after the aero blowing off in the converter is considered in the analog firstly, and the non-isothermal rectification analog models are built.Through the cold model experiment, the bottom aero supplied strength and the bottom lance blocked influences on the stirring uniform time of the molten bath are studied. The stirring uniform time, all factors' influence on the amount of splash , and the influence on the attacked depth, the molten bath erosion effect on the bricking-up are discussed. And the experiments' results show that:(1) Adoptting the completed geometric similarity isothermal analog method, the experiments are carried out. And the conclusions are obtained as below: the reasonable bottom aero supplied strength for the Chongqing Iron and Steel Co. Ltd's converter whole service lives is between the 0.06 m3/min.t and 0.11 m3/min.t. and through the experiment applying the rectification analog method, the conclusion of the bottom aero supplied strength less than the completed geometric similarity, the value is about 0.04m3/min.t and effected by the lance position's change and the phase of different smelting process slightly.(2)The stirring uniform time under the entirely open or partial blocked combined blowing stirring needed time shorter than under the conditions of the only top blown, namely the bottom supplied aero blocked completed. The results show that the stirring and metallurgy effectiveness under the condition of combined blown are better than that of the only top blown; and under the combined blown conditions, the stirring effectiveness when the decentration bottom lance blocked partial are better than that under the condition of the symmetry bottom, and the bottom blown without the top blown has the best stirring effectiveness.(3)Under the condition of combined blown, the stirring effectiveness under the fundamental position is the best and the stirring uniform needed time is the least. Above the basic lance position of given range, the stirring uniform time increase slowly. And the stirring uniform needed time is longer under the condition of the over-low lance position.(4)When the smelting process enter into the oxygenizing decarbonization stage, the steel, slag, and aero form emulsifying molten bath, the bottom aero supplied strength or the lance position's influence on the stirring uniform is weaker than that at the time of early smelt stage. the main reasons are that the top blown aero flow has stronger stirring effect and position the dominant place, so that stirring uniform needed time cut down obviously.(5)Under the basic lance position, the bottom blowing aero supplied strength has trivial effect, but the extreme strong supplied aero can increase the converter's splash. And the amount of splash rising as the lance position lifting, but when the lance position raised to given degree, the top blown's impact energy on the molten bath fall down, and the amount of splash reduce.(6) The fluid erosion effect on the converter wall is higher than that of the molten steel at the same position under the condition of steel and slag emulsifying. After forming the steel, slag, aero emulsification, the erosion effect on the bottom of the converter caused by the top blown weaken, and the erosion on the converter is the most serious. The simulation computing models are established, and the fluid-flow simulation are carried out applying the PHOENICS software. The results are listed as following.(1)Under the simulation condition, the center of the converter bottom is the bottom blown stirring dead zone, and the dead zone ,in which the molten steel flow slowly and the dynamics conditions are bad, become the restrictive segment of the condition for the bott...
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