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混合时间是评定搅拌设备混合效率的重要指标,为了检测带有挡板和导流筒的搅拌槽内液-固-固三相流场的混合时间,以甘油溶液为液相,砂子和赤泥为固相建立了流场体系,采用电导法测量体系的混合时间.并对流场进行了计算流体动力学(CFD)模拟研究,CFD模型采用基于欧拉多相流模型和RNGκ-ε湍流模型.流场混合时间模拟结果与实验结果的偏差较小,说明该CFD数学模型能很好地预测流场的混合时间.体系的混合时间随搅拌转速的增大而减小,当流场的轴向混合占主导地位时,增设导流筒可减小流场的混合时间.导流筒对于粒径和密度较小的固体影响较大.“,”The mixing time is an important index to evaluate the mixing efficiency of the mixing equipment.In order to detect the mixing time of the liquid-solid-solid three-phase flow field in the stirred tank equipped with baffles and draft tube,a flow field system using the glycerol solution as the liquid phase,the sand and red mud as solid phases was established and the mixing time of the system was measured by electrical conductivity method.The computational fluid dynamics (CFD) simulation of the flow field was carried out.The CFD model was based on the Eulerian multiphase model and the RNG κ-ε turbulence model.The simulation results indicated that the CFD model could well predict the mixing time of the flow field due to smaller deviation of between the simulation and experimental results.The mixing time decreased with the increase of the stirring speed,and when the axial mixing of the flow field was dominant,the mixing time of the flow field can be reduced by adding the draft tube.The draft tube had a great influence on the solids with smaller particle size and density.