【摘要】 在壁面滑移的边界条件下 ,利用聚合物流体计算软件包POLYFLOW对两种熔体的二维等温共挤出进行了数值模拟 .在两侧壁面滑移系数相同和两侧壁面滑移系数不同这两种情形下分别计算了共挤出流动的速度场、压力场、黏度场及剪切速率场 ,讨论了壁面滑移对共挤出流场、界面形状和挤出胀大的影响 .模拟结果表明 :当两侧壁面滑移情况相同时 ,滑移系数越大 ,界面偏移越大 ,熔体胀大率增大 ;当两侧壁面滑移情况不同时 ,滑移系数相差越大 ,界面偏移越大 ,滑移系数小的一侧熔体挤出胀大显著更多还原

【Abstract】 Numerical study of two-dimensional isothermal bi-component co-extrusion under wall slip boundary conditions was performed by using POLYFLOW package.The distributions of velocity, pressure, viscosity and shear rate for co-extrusion flow field were solved, with and without the same wall slip coefficients on both wall sides respectively.The effects of wall slip on co-extrusion flow field, interface shape and extrudate swell were discussed. The simulation results revealed that, when wall slip coefficients were kept the same on both wall sides, both interface shift and extrudate swell ratio increased with slip coefficients; when wall slip coefficients were different on both wall sides, interface shift became more significant as the difference of slip coefficients increased, and the melt with a smaller slip coefficient swelled more evidently.更多还原