同向双螺杆挤出机中齿形元件的流动和混合模拟

Flow and Mixing Simulation for Turbine Mixing Elements in a Co-rotating Twin Screw Extruder

应用POLYFLOW软件,采用三维非等温、Cross模型,对高聚物熔体在双螺杆挤出机齿形元件和断裂螺纹元件中的流动和混合过程进行了数值模拟,并用示踪粒子法研究了不同颜色粒子的流迹和停留时间、剪切速率、剪切应力、拉伸速率的分布。在此基础上,对两种元件的分布性混合和分散性混合性能进行的量化分析对比发现,与断裂螺纹元件相比,齿形元件有着弱的输送能力和建压能力,强的轴向温升能力,强的分布性混合能力和分散性混合能力。

Non-Newtonian and non-isothermal flow simulations based on 3D FEM were applied to the turbine mixing element(TME) and the screw mixing element(SME) with POLYFLOW. Additionally, marked particle tracking analysis was carried out to evaluate the distributive and dispersive mixing judging from residence time distribution,shear rate distribution,stretching rate distribution and distributive performance of material points. The SME was examined in order to contrast flow and mixing patterns with the TME. Using the above analyses, the comparison of flow behavior and mixing performance of the TME and the SME was obtained.