微尺度下H形分布流道充模流动不平衡特性  

Numerical Simulation of Imbalance Characteristics of Filling Flow in H-Shaped Distribution Channel at Micro Scale

作　　者：徐斌[1] 杨波[1] 安晓玉 杨朝龙 Bin Xu;Bo Yang;Xiaoyu An;Chaolong Yang(Key Laboratory of Testing Technology for Manufacturing Process,Ministry of Education,Southwest University of Science and Technology,Mianyang 621010,China;CRRC Tangshan Co.Ltd,Tangshan 063000,China)

机构地区：[1]西南科技大学制造过程测试术教育部重点实验室,四川绵阳621010 [2]中车唐山有限责任公司,河北唐山063000

出　　处：《高分子材料科学与工程》2022年第3期113-121,共9页Polymer Materials Science & Engineering

基　　金：国家自然科学基金资助项目(51475395)。

摘　　要：为探究微尺度下的充填不平衡与传统注塑的不同,考虑微尺度下的影响充填不平衡的关键因素包括尺度效应、壁面滑移和对流换热,采用聚甲醛(POM),对H形对称分布的半圆形截面微流道系统进行了充模流动数值模拟实验。通过分析浇口处对称点间温差数据,实验结果表明壁面滑移能有效降低对称点间温度差,对充填不平衡有较明显的改善作用。对流换热使流道内熔体的一部分热量通过模具散失,加剧了充填不平衡,且对流换热系数越小,充填不平衡越明显。随着流道尺寸的减小,壁面滑移越明显,对流换热使对称点间温差变小,有利于改善充填不平衡。In order to explore the difference between the filling imbalance in micro-scale and traditional injection molding,the key factors affecting the filling imbalance in micro-scale include scale effect,wall slip and convective heat transfer.The numerical simulation experiment of filling flow in H-shaped semi-circular cross section microchannel system with symmetrical distribution was carried out by using polyoxymethylene(POM).By analyzing the temperature difference between the symmetrical points at the gate,the experimental results show that the wall slip can effectively reduce the temperature difference between the symmetrical points and improve the imbalance of filling.Convective heat transfer makes part of the heat of the melt in the flow passage dissipate through the mold,aggravating the imbalance of filling,and the smaller the convective heat transfer coefficient,the more obvious the imbalance of filling.With the decrease of the flow channel size,the wall slip becomes more obvious,and the convective heat transfer reduces the temperature difference between the symmetrical points,which is beneficial to improve the filling imbalance.

关 键 词：微尺度流道 尺度效应 壁面滑移 对流换热 充填不平衡 

分 类 号：TQ320.662[化学工程—合成树脂塑料工业]