应用流动可视化技术,考察了低密度聚乙烯熔体流径突然收缩轴对称口模时的入口收敛流型.发现在口模入口前区的两侧存在明显的环流区;环流区长度(LV) 随着挤出速率和流道收缩比的增加而增大.采用前文发表的LV公式计算了实验条件下试样的LV值.结果表明,预测值与实测值之间有较好的一致性.
参考文献
[1] | Cable P J;Boger D V .A comprehensive experimental investigation of tubu lar entry flow of viscoelastic fluids:Part.I.Vortexcharacteristics in stable flo w[J].AICHE Journal,1978,24(05):869-879. |
[2] | Biding D M .An approximate analysis for Contraction and converging flow s[J].Journal of Non-Newtonian Fluid Mechanics,1988,27:173-189. |
[3] | Liang J Z .Comverging flow of non-Newtonial fluids through an abrupt co ntraction[J].ASTM,1995,231(66):35-37. |
[4] | Liang J Z;Huang Y Q;Tang G J .A study of the flow behaviour of rubber compound melt through extrusion dies with different entry angles[J].Plast Ru bber Compos Proces Appl,1992,18(05):311-315. |
[5] | Liang JZ .Estimation of vortical regionlength of rubber compound during entry flow[J].Plast Rwbber Compos Process Appl,1996,25(10):495-498. |
[6] | 梁基照.低密度聚乙烯挤出流变特性的研究[J].高分子材料,1992(04):11-13. |
[7] | 梁基照 .非牛顿流体自然收敛半角方程的实验验证[J].化工学报,1996,47(06):755-757. |
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