Abstract:

The finite element method was used to compare and analyze fluid flow and mixing characteristics between three kinds of rotor mixer, 4WS,4WH and 6WI.The UG software was used to build 3D geometry models. The Gambit software was used to be grid division. And model was used to simulate the flow field of three kinds of internal mixer by BirdCarreau constitutive model and Polyflow software. By comparing the average velocity, the axial velocity and the shear rate, the flow patterns of the three flow fields were obtained. At the same time, the distribution of the mixture of the three parameters was described by using the parameters of the particle index, the average logarithmic stretch index, the probability of the particle index, the average mixing efficiency and the residence time distribution. The simulation results showed that, because of the special variable clearance rotor structure of 6WI rotor mixer, the flow field was more easily changed, and its mixing performance was higher than that of the other two kinds of rotor mixer.

Key words: Mixer, Finite element simulation, Dispersive mixing, Distributive mixing, Mixing intensity

摘要： 利用有限元法对4WS、4WH 和6WI三种转子密炼机流体的流动和混合特性进行了对比分析。利用UG软件进行三维几何建模,利用Gambit软件进行网格划分,同时采用Bird-Carreau本构模型及Polyflow 软件对三种转子密炼机的流场进行了三维等温数值模拟对比研究。通过对平均速度、轴向速度和剪切速率等进行对比,得到了三者流场的流动规律。同时,利用粒子对数拉伸指数、粒子平均对数拉伸指数、粒子拉伸指数概率、平均混合效率概率和停留时间等参数对三者的分布混合情况进行描述。模拟结果表明,由于6WI转子密炼机本身所具有的特殊变间隙转子结构,更易改变流场的规则流动,其混合性能高于其他两种转子密炼机。

关键词: 密炼机, 有限元模拟, 分散混合, 分布混合, 混合效率