方柱绕流中聚乙烯熔体流变行为的数值模拟  

Numerical Simulation of Rheological Behavior of Polyethylene Melts Through a Square Cylinder

作　　者：李文文[1] 王伟[1,2] 

机构地区：[1]青岛科技大学橡塑材料与工程教育部重点实验室,山东省橡塑材料与工程重点实验室,山东青岛266042 [2]大连理工大学工业装备结构分析国家重点实验室,辽宁大连116024

出　　处：《中国塑料》2015年第10期68-72,共5页China Plastics

基　　金：国家自然科学基金资助项目(21274072);工业装备结构分析国家重点实验室开放基金(GZ1213)

摘　　要：采用了DCPP和S-MDCPP两种模型分别描述低密度聚乙烯熔体的本构行为。在迭代分步算法中引入了改进的有限增量微积分(FIC)法,并采用离散的弹性-黏性应力分裂技术(DEVSS)/迎风流线(SU)法解决黏弹性流动分析中的对流占优问题。讨论了S-MDCPP模型预测的速度、压力及主链拉伸分布随Weissenberg(W_i)数的变化。结果表明,两种模型预测的速度、主应力差等色条纹和主链拉伸分布吻合较好;随W_i的增大,速度及压力均增大。The constitutive behavior of low-density polyethylene （PE-LD）were described by the DCPP and S-MDCPP models in this study. The modified finite increment calculus （FIC） procedure was introduced into the iterative fractional step algorithm, and the discrete elastic viscous stress split （DEVSS） and streamline-upwind （SU） techniques were employed to cope with the convection dominated problem of the viscoelastic flow analysis in order to enhance the computational stability. It showed that the velocity, isochromatie fringe pattern of principle stress difference and backbone stretch distributions predicted by the DCPP and S-MDCPP models agreed very well. Moreover, the predicted velocity, pressure and backbone stretch distributions using the S-MDCPP model at different Weissenberg numbers （Wi） were discussed and it exhibited the velocity and pressure were enlarged with the increase of Wi.

关 键 词：流变学 黏弹性流 高分子熔体 本构模型 数值模拟 

分 类 号：TQ325.12[化学工程—合成树脂塑料工业]