微尺度通道中的高聚物熔体流动行为与宏观熔体流动有许多不同.基于对微注塑成型中的熔体充模流动特性的理论分析,建立了微小通道中熔体流动的表面张力模型,并以不同的表面张力系数和不同接触角,对矩形微通道中的熔体流动速度分布进行了数值模拟.结果表明,接触角小于90°时,熔体在通道壁面附近具有最大速度;接触角大于90°时,熔体在壁面处具有最大速度.无表面张力时,熔体填充流动所需时间明显长于有表面张力时的填充时间,即表面张力对微小通道中的熔体流动具有促进作用.
The behavior of polymer melt in micro scale is different from that in macroscopic scale in many aspects.Based on the theoretical analysis of flow characteristics in filling flow of micro injection molding, the melt flow model of surface tension in micro channels was developed.The distribution of melt flowing velocity in rectangular cross-section micro-channel was simulated with different surface tension coefficients and various contact angles.The results indicate that the melt flow maximum speed occurs near the wall of micro channel when the contact angle is less than 90°while when the contact angle is more than 90°the melt flow maximum speed remains in the wall.The melt filling time required without surface tension is significantly larger than that with surface tension, that is to say that surface tension can promote the melt filling flow in micro channels.
参考文献
| [1] | V. Plotter;N. Holstein;K. Plewa;R. Ruprecht;J. Hausselt .Replication of micro components by different variants of injection molding[J].Microsystem technologies,2004(6/7):547-551. |
| [2] | Chien RD;Jong WR;Chen SC .Study on rheological behavior of polymer melt flowing through micro-channels considering the wall-slip effect[J].Journal of Micromechanics and Microengineering,2005(8):1389-1396. |
| [3] | Chen CS;Chen SC;Liaw WL;Chien RD .Rheological behavior of POM polymer melt flowing through micro-channels[J].European Polymer Journal,2008(6):1891-1898. |
| [4] | L.Yu;L.J.lee;K.W.Koelling .Flow and Heat Transfer Simulation of Injection Molding With Microstructures[J].Polymer engineering and science,2004(10):1866-1876. |
| [5] | Yao DG.;Kim B. .Simulation of the filling process in micro channels for polymeric materials[J].Journal of Micromechanics and Microengineering,2002(5):604-610. |
| [6] | Kim DS.;Lee KC.;Kwon TH.;Lee SS. .Micro-channel filling flow considering surface tension effect[J].Journal of Micromechanics and Microengineering,2002(3):236-246. |
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