为稳定地求解速度、压力、温度并准确跟踪流动前沿,实现三维塑料注射成形充模过程数值模拟,采用迦辽金最小平方法(GLS)消除因速度和压力的不当插值组合导致的数值震荡问题,建立了速度与压力同次插值的对称、稳定的集成有限元计算格式;用流线迎风Petrov伽辽金法(SUPG)消除因能量方程中的对流项而导致的数值震荡问题,建立了能量场的稳定有限元计算格式.比较了不同网格密度对计算结果的影响,并通过与文献中实验结果及现有的商业分析软件Moldflow的模拟结果对比,表明提出的数值模拟方法具有良好的稳定性和精度.
In order to solve the speed, pressure, temperature stably and advance melt front exactly in the simulation during filling stage of 3D plastic injection molding, the GLS (Galerkin/least-squares) formulation was employed to prevent the potential numerical instabilities, thus resulting in the symmetric and stabilized finite element integration formulations using equal-order interpolation functions for velocity and pressure. SUPG (streamline-upwind/Petrov-Galerkin) formulation was applied to avoid oscillations due to convection term of the energy equation. Several numerical examples were studied and the developed algorithms were shown to perform stably when different mesh densities were used and give accurate results compared with experimental data in a reference and the wellknown commercial software Moldflow.