用迭代法模拟注塑成型的三维流动

Hele-Shaw模型是模拟注塑成型过程的常用模型,它的主要缺点是不能模拟一些重要的物理现象及引入实际制件中并不存在的“中面”概念,为了消除这些不足,本文开发了真三维的流动分析程序。建立了粘性、不可压缩的非牛顿流体流动的控制方程,为了避免同时求解耦合的压力场、速度场,本文引入拟稳定技术独立地求解这些方程,用迭代法求耦合方程的解。这种方法可以减少内存并提高数值方法的稳定性。算例表明数值结果与实验结果吻合较好,这种方法成功地模拟了注塑成型流动过程中的重要特征。

3D Flow Simulation of Injection Molding with Iterative Method

The major drawbacks of the Hele-Shaw approximation,commonly used today as a mean of simplifying the simulation of the injection molding process,are inherent loss of the ability to predict important physical phenomena and the ambiguity involved in the definition of a mid-plane.To overcome the difficulties,a fully three-dimensional mold filling simulation program is developed.The governing equations are established for incompressible,non-Newtonian fluid under non-isothermal conditions.To avoid the simultaneous determination of these fields,a quasi-steady technique is introduced to solves the components independently at any given time step.The iterative procedure is employed to get the final solution of the coupled equations.It is found that the memory requirements are reduced and the stability of numerical scheme is enhanced during the whole simulation.A good agreement with the experiments dernonstrates the capacity of this method to predict important flow features in injection molding.