注水工艺对水辅共注过程影响的数值模拟  

Numerical Simulation of the Influence of Water-Injection Process on the Water-Assisted Co-Injection Molding

作　　者：章凯[1] 匡唐清[2] 柳和生[1] 曾效舒[3] 

机构地区：[1]南昌大学聚合物加工实验室,江西南昌330031 [2]华东交通大学机电工程学院,江西南昌330013 [3]南昌大学机电学院,江西南昌330031

出　　处：《高分子材料科学与工程》2013年第11期177-182,共6页Polymer Materials Science & Engineering

基　　金：国家自然科学基金资助项目(51103037);江西省自然科学基金资助项目(2010GQC0029)

摘　　要：在水辅助共注射熔体层流填充模型基础上,在水相注入时引入了湍流形式的流体控制方程替代以往常用的层流假设,建立了水相注入时湍流流动形态的理论模型以及数学模型。采用有限体积法对整个水辅共注成型的填充过程进行模拟,同时考虑皮层熔体前沿的"喷泉"效应,不对熔体厚度进行人为的设定,研究了注射水的速度、温度以及延迟时间对产品形貌的影响。结果表明,随着注水速度的增加,注水温度的降低和注水延迟时间的缩短,水相穿透深度和熔体残余壁厚减小,同时中空成型率增大。At present, the laminar flow hypothesis is adopted mostly during water injection in the water-assisted injection molding process. This hypothesis doesn＇ t consider the turbulence flow of water. Further more, fountain flow of skin melt front is aim ignored and wall thickness is artificially determined. In this paper, the laminar flow model and the turbulence flow model were adopted to describe the flow behaviors of polymer melts and water during the filling stage of water-assisted co-injection molding process respectively. Fountain flow at melt front was considered and wall thickness was formed naturally. The whole filling process was simulated by Volume of Fluid （VOF） method. The influence of water injection speed, water injection temperature and water injection delay time on the feature of products were investigated. The results show that, as the water injection speed increases, water temperature decreases or the delay time of water injection decreases, the penetration length of water and residual wall thickness of melt decrease while the hollow forming rate increases.

关 键 词：水辅共注 数值模拟 湍流 

分 类 号：TQ320.66[化学工程—合成树脂塑料工业]