| XJM-S series flotation cell is a kind of mechanical-stirring type flotation machine, which is widely applied in coal preparation. In this paper, Fluid Mechanics software FLUENT was used to analyze the fluid field characteristics of the XJM-S8 flotation cell. And software PRO/E was applied to set up 3-D entity model. While software GAMBIT was served for grid partition in the calculation region. This paper adopted finite volume method as discretization method, selected the standard k-εturbulent flow model as well as used pure water as medium to simulate and analyze the characteristics of the flotation cell. By numerical simulation, the pressure distribution of the impeller-stator region, the streamline diagram as well as the speed distribution graph of the liquid at different sections within the flotation cell could be obtained. In addition, the distribution and the evolution pattern of the turbulent kinetic energy, turbulence intensity, turbulence dissipation rate and other characteristics parameters could also be gained. Through the impeller-stator region simulation analysis, it was found that, at a certain radius of the impeller blade, the dynamic pressure against the liquid surface was always higher than that on the liquid surface, indicating that the liquid flow velocity against surface was higher than that on the liquid surface; When the fluid entered the stator, the speed decreased due to the hindering effect of the impeller, correspondingly kinetic energy converted to pressure energy. The maximum value of the dynamic pressure, static pressure and total pressure in the blade runner were respectively 36.6kPa,28.9kPa,60.4kPa, while the minimum were respectively 3.0kPa,-35.3kPa,-31.2kPa. The maximum speed of the fluid in the impeller region was 8.56m/s, which was close to the rotational speed of the impeller 8.9m/s. Through the analysis of the fluid stream line in the flotation cell, it was found that the flow state was "W"-shaped three-dimensional of periodical movement. The lower part was vertical eddy movement while the upper flow was steady, which is consistent with the flotation process requirements. After the flow got through the stator, the flow was evenly distributed along the horizontal section the due to the orientation of the eddy plate flow board, there was no dead zone, indicating the structure of flotation machine is reasonable. Through the analysis of turbulence characteristic parameters, it was found that turbulent kinetic energy, turbulence intensity, turbulence dissipation rate distribute symmetry to the impeller center; The stirring region of the XJM-S8 flotation machine lied below 0.7m in the lower part of the regional body, while above 0.7m or more, it was the flotation separation region which was relatively stable. The turbulent intensity of the stirring region was six times than that of the flotation separation region. Turbulence intensity is proportional to the speed of the speed of the impeller. The constant rotational speed of the impeller is a similar criterion to the simulation of enlarged movement of XJM-S-type flotation machine to ensure similar turbulence intensity. Through numerical simulation of flow field analysis, characteristics of the flow field of XJM-S-type flotation cell can be deeply understood so that a certain theoretical foundation of the research and optimized design of flotation cell has been laid.
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