Abstract: The geometric models and finite element models of triscrew extruder with different rotors have been established, and the models have been simulated by Polyflow. The mixing index, shear rate, logarithm of stretching, instantaneous efficiency, the average time efficiency and other evaluation parameters have been calculated using particle tracking method. The results show that, the number of shear and stretching in triscrew extruder in the same period increase with the increase of screw head numbers. Accordingly, the mixing effect is also increased gradually.

Key words: Triscrew extruder, Numerical simulation, Particle tracking method, Mixing efficiency, Mixing index

摘要： 建立了三种不同螺杆类型的三螺杆挤出机几何模型和有限元模型, 运用P o l y f l o w软件对其进行数值
模拟。采用粒子示踪法计算了混合指数、 剪切速率、 对数拉伸指数、 瞬时混合效率和时间平均混合效率等评价参数。
结果表明, 随着螺杆头数的增加, 三螺杆挤出机在相同周期内对物料的剪切和拉伸次数增加, 混合效率逐渐增大。

关键词: 三螺杆挤出机, 数值模拟, 粒子示踪法, 混合效率, 混合指数