注射成形填充模拟的修正算法

Modified Algorithm for Simulation of Injection Molding Process

为提高注射成形过程数值模拟结果的准确性,采用类似迎风法的概念,通过对平流方程作为填充状态控制方程而导致模拟失真原因的分析,提出了相应的数值修正算法.该方法在高效显式数值模拟算法和有限元软件基础上,通过对模型内流体速度场的系统性操作,削弱空气流动速度场对喂料填充的不真实影响,使得填充状态的输送更基于流动前沿面后部的流场作用,并对⊥型和L型模腔进行了数值仿真.结果表明:该方法能有效抑制填充流的失真现象,实现了在流动过程中流向发生大角度变化模腔的正确填充过程.

In order to improve the accuracy of numerical simulation for injection molding process, a notion similar to upwind method was introduced. As the governing equation of the filling state takes the form of an advection equation, distorted simulation result may be induced by the flow of air in the mold cavity. To solve the problem, a numerical correction method was proposed. This method weakens the adverse effect of air flow velocity field on the filling process, by modifying the fluid velocity field through systematic operations based on an efficient explicit algorithm and finite element software. Thus, the advection of filling state mainly depends on the flow field behind the filling front. In addition, a numerical simulation was made in mold cavities of shapes ⊥ and L to verify the effectiveness of the method. The result shows that the proposed method can suppress the distortion phenomenon of filling flow effectively, and ensure a correct filling process in complex channels, in which the flow directions have large-angel changes.