基于HCZ模型的注塑成型充填过程模拟

Simulation of filling stage in injection moulding based on HCZ model

塑料熔体充填过程中的微结构形态对注塑制品性能影响很大,是注塑制品控形、控性的基础,使用格子玻尔兹曼法(lattice Boltzmann method, LBM)中的HCZ(He-Chen-Zhang)模型能模拟注塑过程中复杂的多相流和微结构形态演化过程。通过开发HCZ模型的程序,模拟了模具型腔内熔体流动的Poiseuille流。研究表明,模拟结果与理论解基本吻合,验证了HCZ模型能准确地模拟塑料熔体的非线性流动行为。使用HCZ多相流模型模拟了注塑熔体充填和气辅成型气体穿透过程,模拟的注塑熔体流动前沿'喷泉效应'与实际成型过程相符,气辅成型气体压力不仅影响气道厚度,而且影响厚度的均匀性。

The microstructure in the filling stage has a great influence on the properties of injection moulding products,which is the basis of shape and performance control of injection moulding products.The complex multiphase flow and the microstructure evolution can be simulated through HCZ(He-Chen-Zhang)model of lattice Boltzmann method(LBM).According to HCZ model,a software was developed to simulate Poiseuille flow in mould cavity.The results show that the simulation results are in good agreement with the theoretical solutions,which verifies that the HCZ model can accurately simulate the non-linear flow behavior of plastic melt.HCZ multiphase flow model was also used to simulate the injection melt filling and gas penetration of gas-assisted injection moulding.The'fountain effect'in the front of the simulated melt flow was consistent with the actual injection process.The results show that gas pressure in gas-assisted injection molding not only affected the thickness of the airway,but also affected the uniformity of the thickness.