微通道聚合熔体粘性耗散尺度效应  

Viscous Dissipation Scale Effect on Polymer Melt in Micro Channels

作　　者：徐斌[1] 王敏杰[2] 于同敏[2] 赵丹阳[2] 

机构地区：[1]西南科技大学制造过程测试技术教育部重点实验室,四川绵阳621010 [2]大连理工大学精密与特种加工教育部重点实验室,辽宁大连116024

出　　处：《高分子材料科学与工程》2014年第7期105-109,共5页Polymer Materials Science & Engineering

基　　金："十一五"国家科技支撑计划重点项目(2006BAF04B13);四川教育厅项目(13zd1001);教育部制造过程测试技术重点实验室开放基金(12zxzk07)资助

摘　　要：针对微尺度聚合物熔体流动粘性耗散变化规律,基于流体能量方程进行了理论分析。随着通道特征尺寸的减小,粘性耗散项在能量方程中所占比例在增加,表明粘性耗散作用在增强。选用当量直径分别为1000μm、500μm、350μm的矩形截面和圆形截面毛细管口模,以高密度聚乙烯进行不同温度与不同剪切速率下的粘性耗散实验,计算了单位长度粘性耗散温升。结果表明,随着通道特征尺寸的减小,单位长度粘性耗散温升在增加。当剪切速率从低向高变化时,特征尺寸较小的毛细管口模单位长度温升增加较快。因此,随着通道特征尺寸的减小,粘性剪切摩擦在逐渐增强。The proportion of the viscous dissipation increases rapidly and the effect of viscous dissipation is enhanced when the character size of channel decreases. Viscous dissipation experiments at various shear rate were investigated with HDPE at different temperature when melts flow through 1000 μm, 500 μm, 350 μm equivalent diameter micro channels, including circular cross-section and rectangular section. Average temperature per rise unit length was calculated depending on experimental datum. The results indicate that the average temperature rise per unit length increases with decrease of the channel characteristic size. When the shear rate rises, the average temperature rise per unit length of smaller feature size capillary die increases more rapidly. Therefore viscous shear friction gradually strengthens as the micro channel feature size decreases.

关 键 词：粘性耗散 微通道 聚合物熔体 

分 类 号：O631.21[理学—高分子化学]