Influence Of Computational Fluid Dynamics Parameters On The Flow Field Of The KYF-0.2 Flotation Machine

The movement of bubbles and solid particles in the process of mineral flotation flow field and the distribution of index has an important impact on mineral flotation industry. Flotation machine mechanical properties of multiphase flow link the actual operating parameters of the flotation machine, flotation kinetic parameters and performance up reasonably. Computational fluid dynamics combines the advantages of industrial experiments and theoretical studies well and reduces the costs of study process. But computational fluid dynamics is applied to flotation mechanics still deficiently and the research results are not very accurate. This paper provided using fluid mechanics simulation software CFD and CFX for studying the influence of computational fluid dynamics parameters to multiphase flow system in the KYF-0.2 flotation tank, in order to explore appropriate model parameter values and provide some valuable reference for the subsequent flotation machine computational fluid dynamics simulation. The main work and research results as follows:(1) Under the Euler-Euler model of multiphase flow, regardless in the different conditions of the pure liquid or gas-liquid, solid-liquid two phase, the flow field and velocity distribution coincide with the requirements of the real flotation process, and it embodies the advantage of hydrodynamics calculation software is used for flotation machine design, amplification and improvement.(2) It explores the influence of the drag force and lift force model to the velocity vector field and gas holdup distribution in gas-liquid two phase model in flotation machine tub. Results show that in the conditions rotor speed is 315 r/min, inlet velocity is 5 m/s, the phenomenon of gas phase and liquid phase following together in the model of Schiller Naumann and Ishii Zuber Drag force is more obviously than Grace and Drag coefficient drag force model. And when the value of drag force model Drag coefficient is 8, the dispersion of the gas are better. When the inlet velocity reducing, a smaller drag coefficient value also can get a good gas dispersion. And when the value of drag force model Drag coefficient is 8, the selection of lift force model doesn’t have an obvious effect on the superficial gas holdup distribution.(3) Under the Euler-Euler model of solid-liquid two phase multiphase flow, it explores the effect the drag force model has on the distribution of solid holdup in the condition of speed is 315 r/min, solid particle volume fraction is 12%. Results show that when the drag force model is Drag coefficient, the distribution of solid holdup is not ideal, but Schiller Naumann model will be better. Besides in the Eulerian-Lagrange multiphase flow model, it explores the motion trajectory of one-way coupled and fully coupled solid particles. Results show that this model can simulate the actual motion trajectory of solid particles well in flotation, and the tracking time of fully coupled particle is slightly longer than one-way coupled particle.(4) It explores the relationship between gas holdup and solid holdup, shaft power, circulation when rotor speed is 315 r/min. Results show that in the gas-liquid phase, with the gas holdup increasing, shaft power reducing; In the solid and liquid phase, with solid holdup increasing, shaft power increasing, solid circulation volume also increasing.(5) Under the Euler-Euler model of multiphase flow, the model parameters of gas-liquid and solid-liquid two phase flow simulation used in three-phase flow simulation, it also can get ideal result, reasonable gas holdup and solid holdup distribution.