Numerical Simulation Of Inner Flow Of Type XK-200 Turbine Classifier

As a special fluid machinery, Turbine Classifier is the main equipment for producing ultrastructure particle materials, and play an important role in their production and classification. To improve the performance of Turbine Classifier and optimize its design, it is necessary to analyze the distribution of Inner Flow. Inner Flow of Turbine Classifier is double-phase flow of gas and solid, and very complicated. It is very difficult to measure in site , so it is necessary to explore the simulation research by numerical methods.In the paper ,the R&D situation and the existing problems of turbine air classifier home and abroad are clarified ,a numerical simulation method of studying the whole flow passage based on a new xk-200 type Turbine Classifier developed by a company is presented. According with the characteristics of its inner flow ,a high-performance Turbine Classifier is designed .At the same time, in order to optimize the flow passage of Classifier and design scheme and technical parameters, a suitable numerical simulation method for flow , which is used to simulate and analyze inner flow features of Classifier , is explored .In relation to the R & D of xk-200 type Turbine Classifier, the main jobs areaccomplished in the paper(l)Quantified study of structural characteristic and work principle of xk-200 type Turbine Classifier. While analyzing Geometry of flow passage of preliminary design, this paper found sharp variation. Unsuitable design of the preliminary design is proved through numerical simulation.(2)In order to eliminate the sharp variation of flow section and optimize the flow passage , put forward two modified scheme . Geometries of three scheme including preliminary design is constructed by related software (CAD or PROE).And pre-treatment is finished by software GAMBIT.(3)Classifier is a kind of hydraulic machinery which inner flow is double-phase of gas and solid and its inner flow is very complex, and it is very difficult to computation the flow of whole Classifier. Considered the operation features and that the flow of air phase can reflect the whole inner flow of Classifier, this paper simplified the flow model, and computed and analysis the whole inner flow of Classifier by air phase.(4)In order to optimize and select the scheme , numerical simulation and analysis for the three scheme of xk-200 type Turbine Classifier are taken by the software FLUENT with the same boundary conditions and control parameters .(5)In order to choose the optimum scheme, comparison of magnitude of supersonic velocity at the nozzle outlet, declining distribution of velocity from nozzle outlet to mix-tank, and velocity distribution (tangent velocity, axial velocity and radial velocity) of Classifier inner zone are drawn.The comparison of the simulated results and experimental data of cooperative company show that: Numerical simulation of Classifier inner flow can estimate the diffusion and classification of coarse and fine particles, and solve the key problem of Classifier design, and by numerical simulation, inner flow features can be known and it is significant to design reasonably and adjust the optimum parameters.Numerical simulation of Inner flow can provide some theoretical evidence for designing high accurate and high efficiency air turbine classifier.