基于薄壁件注塑成型过程中液晶高分子流动模拟

Simulation of Liquid Crystalline Polymers Flow in Injection Molding of Thinwalled Molds

对薄壁件注塑成型过程中液晶高分子材料在模腔内的流动情况进行模拟分析。本文以简化的液晶TIF理论为基础,建立了基于Hele-Shaw模型的模腔内液晶流动的控制方程组,运用有限差分法进行数值求解,并用Moldflow软件模拟液晶材料的充模过程。模拟结果显示:压力场中,在模腔入口处的压力最大,向内逐渐减少,并且呈对称均匀分布;分子取向场中,靠近表层的分子取向与液晶流动方向一致,中心层的分子取向排列相对比较随机。

In this article, in view of injection molding process of thin-walled products, the simulation and analysis of liquid crystal polymers flowing through mold cavity were carried out. The governing equations of liquid crystal polymers were built based on simplified TIF theory and the Hele-Shaw model, the solution of equations was obtained by the finite difference method, and the course was simulated by Moldflow software. The results show, in the pressure field, the maximum pressure appeared at the entrance of the cavity and gradually reduced, and the distribution was uniform and symmetrical. In the field of molecules orientation, the molecular orientation near the surface layer was consistent with the flow direction of the liquid crystal polymers, however, the molecular alignment of center was relatively random.