平板Couette流场中聚合物流变性质及分子构象的数值模拟  

Rheological Properties and Molecular Configuration of Polymer Solution in Planar Couette Flow

作　　者：代向艳[1] 欧阳洁[1] 

机构地区：[1]西北工业大学理学院,陕西西安710129

出　　处：《高分子材料科学与工程》2011年第3期157-161,共5页Polymer Materials Science & Engineering

基　　金：国家自然科学基金资助项目(10871159,10590353);国家重点基础研究发展计划(973)项目(2005CB321704)

摘　　要：通过耦合Brown构形场的有限体积法,对基于FENE(Finite Extension Non-linear Elastic)珠-簧链分子模型的平板Couette流动进行了模拟。不但得到了流动过程中的速度、应力等宏观信息,还得到了分子链的位形、分子链的取向角以及拉伸量等微观信息。另外,还研究了弹簧的最大拉伸长度b和Weissenberg数We对聚合物稀溶液流变性质及分子构象的影响。模拟结果表明,随着b和We增大,代表弹性的第一法向应力差增大,分子链的拉伸量增大,取向角减小。但是,b和We对剪切应力的影响相反,即b增大,剪切应力增大;We增大,剪切应力则减小。Brownian configuration field coupled with finite volume method was used to capture the most important features of dynamics of dilute polymer solution.The efficiency of numerical schemes was evaluated by performing FENE bead-spring chain models in transient planar Couette flow.The velocity and stress also the orientation and stretch of polymer molecule were captured.Additionally,the influences of the dimensionless finite extensibility parameter of spring b and Weissenberg number We on rheological properties and molecular configuration of dilute polymer solution were analyzed.The results of simulation show that the increment of b and We makes the first normal stress difference and the polymer molecular extension increase,but the orientation angle of polymer molecule decrease.However,considering the shear stress,the influence of b and We are opposite.Namely,the shear stress increases with increasing b,while the shear stress decreases with increasing We.

关 键 词：模拟 FENE珠-簧链 Brown构形场 有限体积 

分 类 号：O631.21[理学—高分子化学]