基于离散单元法的锥形双螺杆输送及混合机理分析

锥形双螺杆挤出机结构模型与其他普通螺杆挤出机相差很大且构成独特，近年来在聚合物加工行业中发挥了很大的作用。设计螺槽深度与螺杆半径比为1∶2、2∶5、1∶3的三种锥形双螺杆挤出机，通过离散单元法模拟了锥形双螺杆挤出机挤出LDPE、HDPE两种颗粒的过程，分析了锥形双螺杆挤出机螺槽内颗粒速度的变化，同时在不同参数下对三种锥形双螺杆挤出机的输送效率进行了比较。利用EDEM软件对LDPE和HDPE颗粒进行离散元分析，得出不同时刻两种颗粒在三种锥形双螺杆挤出机内的混合情况。结果表明，螺槽深度与螺杆半径比为1∶2的锥形双螺杆挤出机的混合效率优于螺槽深度与螺杆半径比为2∶5、1∶3的锥形双螺杆挤出机。

Analysis of Conical Twin Screw Conveying and Mixing Mechanism Based on Discrete Element Method

The structure model of the conical twin screw extruder is very different from other ordinary screw extruders and has a unique structure.In recent years, it has played a great role in the processing industry. Three conical twin?screw extruders with the ratio of the groove depth to the screw radius of 1∶2, 2∶5, and 1∶3 were designed.The process of extruding LDPE and HDPE particles from the conical twin?screw extruder was simulated by the discrete element method, and the particle velocity change in the groove of the conical twin?screw extruder was analyzed. At the same time,the conveying efficiency of the three types of conical twin screw extruders were compared under different parameters. The discrete element analysis of LDPE and HDPE particles was carried out using EDEM software, and the mixing situation of the two kinds of particles in the three conical twin?screw extruders at different times was obtained.The results show that the mixing efficiency of the conical twin?screw extruder with the ratio of screw groove depth to screw radius of 1∶2 is better than that of the conical twin?screw extruder with the ratio of the groove depth to the screw radius of 2∶5 and 1∶3.