Abstract:The characteristic of two-phase flow field of the pulp suspension in a stirred pot,which is very important for analyzing the liquid-solid suspension mixer,was numerically studied.The investigation was carried out in a flat bottom,cylindrical vessel.The pulp suspension in the stirred pot was simulated by Fluent.The unstructured grid,multi-reference frame(MRF) and standard k-ε turbulent model were used to simulate the mixing flow under 5 different installation heights.Then the streamlines,the pressure distribution on the surface of the mixer blade,the solid volume fraction and the mixing power in the stirred pot were obtained.According to the velocity streamlines,a bigger vortex was formed in this mixer and the main circulation was well performed.In the mean time,the inverted vertebral region and the vortex region were found by the solid volume fraction profile and the distribution law of the solid volume on the vortex surface.The performance of the mixer was assessed by the mixer power coefficient.According to this assessment,it is known that the mixer designed here has good performance.The results are of importance to the optimization of industrial mixers.
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