The Study On Mathematical Model And Numerical Simulation Of Iron Flow Field In KR Desulphurization Process

The technology of KR pretreatment desulphurization has excellent dynamic conditions and has been widely applied both at home and abroad, It is advantageous to the production of low sulfur steel,the study of iron flow field for this process could understand the law of the hot metal flow and provide certain theoretical guidance to improve the mixing effect and the flow state of the molten iron. the study of iron flow field for this process could understand the law of the hot metal flow and provide certain theoretical guidance to improve the mixing effect and the flow state of the molten iron.In this paper, the mathematical model of the single-phase flow and the air- iron two phase flow was studied, and the influence of the mathematical model with different iron flow on the calculation process and calculation results was analyzed, the relatively appropriate mathematical model of single-phase flow and the air- iron two-phase flow was confirmed, and the flow field was studied numerical simulation with the model. finally, the air-desulfurizer-hot metal three-phase flow mathematical model was established in the KR pretreatment desulfurization, and the mixed diffusion behavior of desulfurizer in molten iron was analyzed.① The study of single-phase flow mathematical model for KR pretreatment of hot metal desulphurization has confirmed the suitable turbulence model is standard k-e,the discrete format of control equations is QUICK and solution method of discrete equation is SIMPLE. The study of single-phase flow mathematical model for KR pretreatment of hot metal desulphurization has confirmed the suitable turbulence model is standard k-e,the discrete format of control equations is QUICK and solution method of discrete equation is SIMPLE.① The mathematical model of air- two phase flow was studied for KR pretreatment of hot metal desulfurization, the results of numerical simulation show that: the prediction of liquid level with VOF model is more stable than Euler model and Euler model can simultaneously simulate air diffusion of liquid surface in molten iron. Then through comparison of water model experiment shows that the prediction ability of VOF model on molten iron level has a good accuracy.② The numerical simulation of fluid movement in molten iron tank by using the VOF model shows four different speed regions exist in vortex surface, the area of vortex surface center high-speed region and the overall velocity increases with the speed raising, that is conducive to the involvement of the desulfurizer, the center high-speed region of vortex surface increase with stirrer immersed depth raising, and overall velocity of vortex surface is low. The air entrapment phenomenon phenomenon occurs in the bottom of the vortex surface and the air extends along the wall of blender.③ The hot metal internal flow field distribution of two phase flow is consistent with prediction of single-phase flow, due to the role of the gas-liquid interface, hot metal near the liquid level there is a high turbulent kinetic energy. the study of this article shows that the suitable speed and immersion depth is 120 rpm and 1200 mm within the scope of rotational speed and immersion depth.④ The hot metal internal flow field distribution of two phase flow is consistent with prediction of single-phase flow, due to the role of the gas-liquid interface, hot metal near the liquid level there is a high turbulent kinetic energy. the study of this article shows that the suitable speed and immersion depth is 120 rpm and 1200 mm within the scope of rotational speed and immersion depth.⑤ The hot metal of air- desulfurizer-hot metal three-phase flow has been established and the simulation result shows that desulfurizer particles gather firstly in the hot metal area near the stirring shaft, then diffuse to the area of internal molten iron, the desulfurizer diffusion of hot metal area below blender blades is relatively slow.