Abstract:In order to study the mixing effect of flow and analyze the flow pattern as well as the velocity characteristics in high shear pulp pump, a geometrical hydraulic model of a high shear pulp pumps was established by Pro/E, and solidliquid twophase flow in it was simulated by using the CFD method based on the mixture model, standard k-ε turbulence model and SIMPLEC algorithm. The meshindependence check was conducted to reduce the influence of mesh size on the results.A series of CFD numerical simulations were carried out under different discharges and rotational speeds, respectively, and the results were compared among the cases to identify their influence on the flow field in the pump. The results show that the mixing uniformity of two phases was improved considerably after the solid phase was sheared in the shearing chamber, suggesting the shear pulp pump exhibited a better mixing and homogenizing effect for the solid phase in flow. The rate of two phases mixing becomes slow when the discharge is increased, and the mixing rate and uniformity of two phases are improved when the rotational speed increases.Note that the mixing rate and uniformity of two phases in the impeller but those in the inlet to the impeller are affected in a great deal by a change in the rotational speed.
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