改进型INTER-MIG搅拌槽内固液悬浮特性的数值模拟  

Numerical Simulation of Solid-Liquid Suspension Characteristics in a Stirred Tank with Improved INTER-MIG Impeller

作　　者：周勇军[1] 卢源[1] 陈明濠 梁家勇[1] 

机构地区：[1]南京工业大学机械与动力工程学院,江苏南京211816 [2]深圳市危险废物处理站有限公司,广东深圳518049

出　　处：《过程工程学报》2014年第5期744-750,共7页The Chinese Journal of Process Engineering

摘　　要：应用CFD软件Fluent 12.0和并行计算机工作站对双层改进型INTER-MIG桨式搅拌槽内的固液悬浮特性、临界离底悬浮转速及功率消耗进行数值模拟,分析了在固体体积分数as=30%下,转速n、桨叶离底距离C1和桨间距C2等因素对搅拌槽内颗粒悬浮特性的影响.结果表明,在一定的转速和桨径下,改变C1和C2会改变流场的局部结构,选取适合的C1和C2可使固液混合更均匀,有利于颗粒悬浮和整个搅拌槽传质传热的进行.最佳桨叶离底高度与槽径比为0.36,最佳桨叶间距与槽径比为0.44;在该最佳工况下临界离底悬浮转速Njs=118.3 r/min;得到既能达到完全离底悬浮、又能使搅拌功耗最小的最佳转速为n=124 r/min.The solid-liquid suspension characteristics, critical suspension speed of impeller and power consumption of a stirred tank with dual improved INTER-MIG impeller were numerically simulated with the software Fluent 12.0 on a parallel computer workstation. The effects of rotation speed （n）, impeller off-bottom clearance height （C1） and spacing between impellers （C2） on particles suspension characteristics in the stirred tank were analyzed under the particle volume fraction as at 30%. The results show that at a constant rotation speed and impeller diameter, local structure of flow field changes with C1 and C2, appropriate of C1 and C2 can make solid-liquid mixed more evenly and good for suspension of particles and the mass and heat transfer. The optimal value of C1/D is 0.36, D is the tank diameter, and the optimal value of C2/D 0.44. Under the optimum working conditions, the critical suspension speed of impeller, Njs is 118.3 r/min, and the optimum speed, n, 124 r/rain, which ensures the solids just suspended off the bottom and the minimum consumption of power.

关 键 词：改进型INTER-MIG桨 固液悬浮 临界离底悬浮转速 功率消耗 

分 类 号：TQ052[化学工程]