| Centrifugal fans used for transporting gas containing kinds of dust work at high particle concentration. When centrifugal fans working, particles will inevitably rub, impact, rebound, abrase with and accumulate at blades, these actions are harmful to balance of impellers and reduce using-time of the mechanism. A research was performed for finding regular patterns that the particle volume fraction and particles move into the impellers by numerical simulation of gas-solid two phases flow field in centrifugal fans, so as to forecast the impeller erosion, and then adopt more effective anti- erosion measures.The paper adopted Reynolds Stress Model to enumerate gas flow field in the impeller. The results conform to relevant experimentations. During the whole numerical simulation, Particle Trajectory Model was applied to calculate moving trajectories of different diameters particle and Multiphase Flow Model was adopted to achieve particle volume fraction under different entry concentrations or different diameters particle. Meanwhile the research predicts erosion quotiety of blades and erosion location of the impeller successfully based on Malakoff and Grant Erosion Model.According to the above numerical simulation following conclusions were gained: Some regular patterns of particles movement, particle trajectory is determinative effect to its abrasion;Particle diameter has an effect on its abrasion to blades, in another word different diameter particles have different impact degrees , results in two different abrasion modalities and erosion quotiety;Some regular patterns of particle volume fraction were also gained; Relationship between erosion quotiety and particle volume fraction were determined, but it need experimental research further.All numerical simulation results conform to relevant experimentations. Predications of erosion conform to some referred documents or real erosion behaviors in workshops.Therefore, simulation results are authentic.
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