考虑熔体弹性的壁面滑移对微尺度流动的影响

Study on the Effect of Wall Slip on the Micro-scale Flow Considering Melt Elasticity

基于对Uhland滑移模型的理论分析,采用模型修正方法,建立了考虑熔体弹性的壁面滑移模型,并以PS材料为例,对所建滑移模型进行了数值模拟。模拟结果表明,随着通道特征尺寸的减小,壁面滑移有利于减小熔体的流动阻力,增大流动速度;毛细管流变实验结果与考虑熔体弹性作用的数值模拟结果的变化趋势一致。由此表明,熔体弹性作用对微通道中流动行为的影响不可忽视。

Based on the theoretical analysis of Uhland wall slip model, a wall slip model was developed with model revision method, which took into account the role of melt elasticity in polymer melt filling micro channel. With the model, the numerical simulation was carried out by using PS material. The results indicate that the wall slip can promote the reduction of flow resistance and the increase of flow velocity. The experimental results of capillary flow show that the trend of the melt pressure drop in dies and the trend of various velocity comply with the numerical simulations which consider the elasticity of polymer melt. In view of this, the conclusion is that the effects of melt elasticity on the behavior of filling flow in micro channels can not be ignored.