中国塑料 ›› 2011, Vol. 25 ›› Issue (12): 95-100 .DOI: 10.19491/j.issn.1001-9278.2011.12.025

• 机械与模具 • 上一篇    

基于拉伸流动的串联磨盘挤出机设计与数值模拟

柳天磊 杜遥雪 陈少清   

  1. 佛山震德塑料机械有限公司 五邑大学
  • 收稿日期:2011-03-28 修回日期:2011-09-18 出版日期:2011-12-26 发布日期:2011-12-26

Design and Numerical Simulation of Series Disc Extruder Based on Elongational Flow

Tianlei LIU Yaoxue DU Shaoqing CHEN   

  • Received:2011-03-28 Revised:2011-09-18 Online:2011-12-26 Published:2011-12-26
  • Contact: Yaoxue DU

摘要: 基于拉伸流动机理对传统串联磨盘挤出机磨盘端面形状进行了结构改进,并借助于计算流体动力学软件Polyflow对磨盘混炼段进行了数值仿真,对比分析了锥面磨盘与普通磨盘的剪切速率、拉伸速率、瞬时拉伸混炼效率和平均拉伸混炼效率及锥面磨盘间隙和凸棱高度对锥面磨盘拉伸流场大小的影响。结果表明,与普通磨盘相比,锥面磨盘形成的收敛流道内熔体粒子主要作无旋流,受到更大的拉伸流场和剪切流场作用,可以获得更高的瞬时拉伸混合效率和时间平均拉伸混合效率;锥面磨盘要获得较强的拉伸流场,存在最佳磨盘间隙和凸棱高度。

关键词: 串联磨盘挤出机, 锥面磨盘, 拉伸混合效率, 数值模拟, 统计学分析

Abstract: Based on elongation flow mechanism, structure improvement was carried out on the disc face of traditional series disc extruder. Numerical simulation was carried out on the disc mixing section using CFD software POLYFLOW, and comparative study was performed between taper-face disc and flat-face disc on the shearing rate, stretching rate, instantaneous stretching efficiency and time-averaged instantaneous stretching efficiency, and the effect that disc clearance and disc ledge have on the elongational flow of the taper-face disc. The simulations showed that melt particles in taper-face disc runner took an irrotational flow, experience larger actions governed by elongational flows and shear flows, and get better instantaneous and time-averaged efficiency of stretching compared with traditional disc. Moreover, there existed a proper distance between discs and disc ledge for getting stronger elongational flow.

Key words: series disc extruder, cone disc, stretching efficiency, numerical simulation, statistical analysis