聚合物气辅共挤对挤出胀大影响的数值模拟  

Numerical simulations of effect of polymer gas-assisted co-extrusion on die swell

作　　者：刘勇[1] 肖兵[2] 尹智龙[1] 

机构地区：[1]江西蓝天学院机械工程系,江西南昌330029 [2]江西南昌工程学院机械与电气工程系,江西南昌330099

出　　处：《合成树脂及塑料》2011年第2期54-57,共4页China Synthetic Resin and Plastics

摘　　要：采用计算流体力学软件建立了二维模型,以低密度聚乙烯和聚苯乙烯为研究对象分析二维模型的有限元。对比了气辅共挤和传统共挤过程中挤出胀大与熔体界面分布,研究了气辅共挤和传统共挤对口模压降、剪切速率分布及剪切应力分布的影响,将气辅共挤、传统共挤时口模压降与挤出胀大率的模拟、实验结果做了对比。结果表明:气辅共挤能有效减小甚至消除传统共挤过程中出现的挤出胀大现象,并有助于熔体界面的稳定和降低口模压降;模拟结果与实验结果具有良好的一致性。A two-dimensional model was established with computational fluid dynamics （CFD） software. The finite element analysis for the two-dimensional model was carried out with taking low density polyethylene and polystyrene as research object. The die swell and melt interface distribution in traditional co-extrusion and gas-assisted co-extrusion were compared. The effect of traditional co-extrusion and gas-assisted co-extrusion on the pressure drop through the die and distributions of shear rate and shear stress was studied. The pressure drop and die swell ratio were contrasted between the simulation and experimental data. The results show that gas-assisted co-extrusion can effectively reduce or even eliminate the die swell phenomena and contribute to stability of the interface and reduction in the pressure drop. The simulation results have a good consistency with the experimental ones.

关 键 词：聚合物 气体辅助共挤成型 挤出胀大 数值模拟 

分 类 号：TQ325.12[化学工程—合成树脂塑料工业]