| With the economic society developing, it fully shows that the resources shortage and environment load have aggravated day by day. It is very urgent to exploit new technology to replace the traditional. The smelting reduction ironmaking technology is one of the main research fields. International Iron and Steel sector has not stopped for smelting reduction ironmaking technology development pace. The development for the smelting reduction ironmaking technology was never stopped in the world. This thesis just generates under this background.Using water modeling and mathematical simulation method, the fluid flow characteristics in the Smelting Reduction Furnace(SRF) has been investigated. The study of water modeling has been built on the base of similarity principle. The geometry and dynamic similarly numbers were considered mainly. For water modeling system, water has been used instead of steel and 20# oil has been used instead of slag. The model was made of acrylics, which was in the proportion of 1:1. For dynamic similarity, the similarity number of F′r was considered. The effect of the oil/water ratio, bottom blowing rate, the side of lances and the top of lances on bath stirring have been studied in iron bath of Smelting Reduction Furnace with water modeling. For the mathematical simulation, utilizing the commercial software Fluent, the three dimensional mathematical model were set up according to the theory of computational fluid dynamics. The simple bottom blowing of flow field has been studied, the results of numerical simulation could be examined.From the present physical and numerical simulation research, the following conclusions can be drawn:(1)The effects of bottom blowing flow rate, top blowing flow rate and the top lance level on the mixing time in iron bath of Smelting Reduction Furnace (SRF) have been studied with water modeling. The test of the single lance at bottom showed the tendency that the mixing time reduced as the bottom flowing rate and the thickness of oil increased. For the test of lance at topside, the mixing time decreased as flow rate increased and the mixing time was different when the lance position was different. Comparing the mixing time and the amounts of spraying, the best conditions obtained through the orthogonal experiment were as follows: 9L/min of bottom blowing flow rate, 15m3/h of top blowing flow rate and 350mm of top lance level.(2)The research of side blown found that: Both in the single side blown and the top-bottom combined blown experiment, the main factor affecting the mixing time was the length of side lance in the bath, and the flow rate of side lance and the angle followed. The mixing time in the bath increased with increasing the bottom flow rate and the top flow rate. The best conditions obtained through the orthogonal experiment were as follows: 130mm of the length of side lance, 50°of angle and 6m3/h of the side flow rate.(3)the turbulence models of Standardκ-ε, RNGκ-εand Realizableκ-εhave been used to model the Residence Time Distribution Curve in the single bottom blowing of flow field. Comparing with the results of water modeling, it is found Standardκ-εis the best turbulence model for the Smelting Reduction Furnace, which might be suitable for spray-blow system of the reduction furnace. The oil and water experiment has been studied by the turbulence model of Standardκ-ε, the accuracy of numerical simulation could be got by comparing the density map of water model and numerical simulation. It was found the ratio of gas phase increased and the rate of dead zone decreased with the increasing bottom flowing rate.
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