聚合物异型材挤出胀大全三维等温黏弹性的数值模拟

The Full Three Dimensional Isothermal Viscoelastic Numerical Simulation on the Extrusion Die Swell of Polymer Profile

针对异型材挤出成型流动过程的特点,基于流变学和流体动力学理论,经合理假设,建立了描述其成型过程的三维等温黏弹性理论模型,并通过DEVSS/SUPG,EVSS法,Mini-Element最小元法和罚函数法等稳态有限元技术,建立了与该模型相适应的快速收敛的稳态有限元数值算法,并以此通过有限元数值模拟,系统研究了黏弹流变性能参数和工艺参数对异型材挤出胀大的影响规律.并通过理论分析,揭示了T形异型材挤出胀大机理.本文的数值模拟研究结果与传统的挤出实验研究结论相吻合.

Based on the characteristic of the plastic profile extrusion process and the theories of rheology and hydrokinetics etc. , under reasonable assumption, the three dimension isothermal viscoelastic theoretical model of describing profile extrusion process was formulated, and the corresponding stable numerical algorithm with fast convergent was established by the stable finite element techniques of the DEVSS/SUPG method, EVSS method, MiniElement method and penalty function method. Based on the finite numerical simulation code of above research, the influencing rules of viscoelastic property parameters and process parameters on the die swell of plastic profile extrusion were systematically studied. The influencing mechanism of the die swell of T polymer profile was disclosed by theoretical analysis and the numerical simulation results were in accordance with conclusions of the traditional extrusion experimental research.