层叠流道中聚合物共挤过程的数值模拟

Numerical Simulation of Polymer Co-extrusion Process in Laminated Runner

采用Bird-Carreau本构方程,利用Polyflow分析软件对尼龙6(PA6)/三元乙丙橡胶(EPDM)熔体在叠层流道中的共挤过程进行了三维等温黏弹数值模拟,对比分析了2种熔体在不同体积流率下在叠层流道中的压力场、速度场和层间界面位置和形貌的情况。结果表明:入口体积流率的变化对界面的位置和形貌有很大影响,当PA6和EPDM的入口体积流率分别为Q1=Q2=1.5 mm3/s时,PA6熔体在流动过程中逐渐侵入到EPDM熔体的流动空间中,出现界面偏移现象;当PA6和EPDM的入口体积流率分别为Q1=1 mm3/s,Q2=2 mm3/s时,无界面偏移现象,共挤物形态良好。

Polyflow software with bird-carreau constitutive equations was used to stimulate the three-dimensional isothermal viscoelastic numerical model of PA6/EPDM melt in laminated runner. The velocity field,the pressure field distribution, and the interface pattern were compared and analyzed in the case of different volume flow rate. The results showed that the PA6 melt gradually invaded into EPDM melt ＇ s flow space,the interface appeared offset phenomenon when the inlet volumetric flow rate of PA6 and EPDM were Q1 =4 Q2 = 1.5 mm^3/s. When the inlet volumetric flow rate of PA6 and EPDM were respectively Ql = 1 mm^3/s and Q2 =2 mm^3/s,There wasn＇t interface offset phenomenon and co-extruded melts were in good shape.