吹塑薄膜与外部冷却空气流场耦合数值模拟  

Numerical Simulation of Coupling Cooling Air Flow to Film Blowing Model

作　　者：麻向军[1] 赵中森 

机构地区：[1]华南理工大学聚合物成型加工工程教育部重点实验室聚合物新型成型装备国家工程研究中心,广东广州510640

出　　处：《塑料工业》2017年第5期56-60,共5页China Plastics Industry

摘　　要：为了研究挤出吹塑薄膜的冷却成型过程,利用计算流体动力学(CFD)软件Polyflow和Fluent对吹塑薄膜和外部冷却空气流场进行了耦合数值模拟。结果表明,薄膜外表面换热系数在风环出风口以下很小,在出风口附近快速增大到最大值后又快速减小,而离开风环一定高度后缓慢下降,膜泡在风环所在高度区域内吹胀较大,随后吹胀比变化缓慢;固定冷却空气流率时,增加风环出风口间隙,换热系数最大值减小且最大值所在位置升高,薄膜在风环高度区域吹胀比减小;固定风环出风口间隙时,增加冷却空气入口流率,换热系数最大值增大且最大值所在位置降低,薄膜在风环高度区域的吹胀比增大。In order to investigate the cooling process and film forming of blown film, the film blowing and external cooling air flow were analyzed by a coupling numerical simulation with CFD softwares including Polyflow and Fluent. The results show that the heat transfer coefficient is tiny below the clearance of air ring, and it increases rapidly to the maximum and then decreases rapidly in the vicinity of the outlet, finally declines slowly after leaving the air ring. The bubble enlarges rapidly near the air ring, and then the blow-up ratio changes slowly above it. When the flow rate of the cooling air is fixed, with the increase in the clearance of the air ring, the maximum value of the heat transfer coefficient decreases while the position where the maximum value occurs lifts up and the blow-up ratio at the position of the air ring decreases. When the clearance of air ring is fixed, with the increase of the flow rate of cooling air, the maximum value of heat transfer coefficient increases and the position of maximum value is lowered. And the blow-up ratio at the position of the air ring increases.

关 键 词：数值模拟 膜泡形状 换热系数 冷却风环 

分 类 号：TQ320.721[化学工程—合成树脂塑料工业]