微注塑成型流动中熔体壁面滑移的研究

基于宏观熔体流动的基本理论及其流动过程中壁面滑移机理的分析,针对微注塑成型模具中熔体充模流动时的壁面滑移行为,建立了微小通道中高聚物熔体流动的壁面滑移理论模型。并用数值模拟方法,对不同滑移系数时微小通道中熔体的壁面滑移对流动速度、熔体压力等的影响进行了研究。结果表明,微小通道中的壁面滑移可使壁面处熔体的流动速度增加,压力损失减小,有利于熔体的充模流动。

Study on Wall Slip in Micro Injection Molding Flow

Miniaturization of the channel size makes the flow behaviours of polymeric melt different from the macroscopic fluid at some aspects,and the neglected factors in macroscale for melt flowing may become the main influencing factors in microscale.The theoretical model of wall slip in microchannels was built to character melt slip behaviour at filling stage in micro injection molding on the basis of the primary theories of macroscopic melt flow and the investigation of the mechanisms of wall slip.By means of the numerical simulation method,the effects of wall slip on the flow velocity,the melt pressure and the local shear rate in the microchannels with different slip coefficients were studied.The results show that the wall slip in microchannels makes the melt velocity increased and the pressure loss decreased,which advances the melt filling flow.