双层组合叶轮的搅拌槽对液固两相流的数值模拟  

Numerical Simulation of the Liquid-solid Two-phase with Double-layer Combined Impeller in a Stirred Tank

作　　者：李新明[1] 严宏志[1] 吴波[1] 徐海良[1] 

机构地区：[1]中南大学高性能复杂制造国家重点实验室,长沙410083

出　　处：《机械科学与技术》2013年第3期388-394,共7页Mechanical Science and Technology for Aerospace Engineering

基　　金：国家自然科学基金项目(50975290);湖南省自然科学基金项目(11JJ5028)资助

摘　　要：采用液固两相流的方法进行数值模拟,运用Fluent软件,利用多重参考系法(MRF)、Eulerian多相流模型、RNG k-ε湍流模型进行仿真,分析双层搅拌桨在立式搅拌槽不同工况下槽内的流场流动及搅拌功率特性。结果表明:不同组合叶轮对流场宏观流动特性影响显著,当上下层叶轮结构不同时,混合液的湍动能增强,循环流动增强,混合效果提高,故选择双层上斜下直搅拌桨作为最优桨型。在此基础上分析搅拌功率,转速大搅拌功率大;粒径增大,搅拌功率先减小后增大;颗粒体积分数对搅拌功率影响不明显,对比模拟值与实验值的最大误差为15%。In this paper , the method of liquid-solid two-phase ilow is used to simulate w^tn me mumple reierence frame （MRF） , the Eulerian muhiphase flow model, the RNG k-8 turbulence model in the fluent software , and the characteristics of flow field and stirring power of double-layer impellers is analyzed under different conditions in the vertical stirred tank. The results show that different combined impellers have affected the macroscopic flow charac- teristics significantly. When the upper and lower impellers are different, the turbulent kinetic energy of the mixture is enhanced, circular flow is increased, and the mixing effect is improved, so we choose the double-layer upper-in- clined lower-vertical impeller as the optimal impeller. On analyzing the stirred shaft power, it is concluded that the larger rotational speed has a larger stirring power, and with particle size increasing, the stirred power increases after a decrease, and particle volume fraction has a light effect to the stirred power, and the maximum error between the simulation and experimental results is 15%.

关 键 词：液固两相流 数值模拟 FLUENT 立式搅拌槽 

分 类 号：TH137[机械工程—机械制造及自动化]