中文摘要：

用有限元方法对两种不相容聚合物熔体在共挤出流道内的流动进行了三维数值模拟，计算了共挤出流动过程的速度场、压力场和应力场．根据数值计算的结果得到了沿流动方向和宽度方向的共挤出界面变化，并分析了入口体积流量和聚合物材料参数对共挤出界面偏移的影响．结果表明：宽度方向共挤出界面的形状和位置沿聚合物流动的方向不断变化；界面偏移量的大小随着流量差异的增加而增大；聚合物入口流量的变化是导致共挤出界面位置变化的决定性因素，流量比的变化对出口处界面形状的影响不大；两种聚合物粘度的不同会导致界面偏向粘度较低的熔体一侧．

英文摘要：

A finite element method was used to simulate the incompatibility polymer coextrusion process. The distributions of velocity, shear stress and pressure inside the eoextrusion die path were obtained by the numerical calculation. Using the three-dimensional model, the interfaces in width was also obtained. The effects of inlet flow flux and material properties of each layer on interface location and shape were discussed. The results indicate that the interface curve in width varies along the flow direction. The flow rate ratio controls the coextrusion interface location. The interface deviate value increases with the increasing of the flow rate ratio. The difference viscosity of two layers polymer leads to the interface deflecting towards the lower viscosity side.