【摘要】 建立了振动力场作用下单螺杆挤出机计量段物理模型,在Stokes假设基础上,得到了螺槽内牛顿流体速度分布的解析解。采用自适应步长4阶Runge-Kutta方法,对动态混合过程进行三维数值模拟追踪,计算了示踪剂构形依时演变及界面拉伸速率,对动态混合过程进行了实时表征。结果表明,低频振动时,螺槽内的混合仍然是规则的层流混合,混合效果有待于进一步提高,指出了进一步提高混合效果的措施。更多还原

【Abstract】 The model of the metering zone of the single screw extruder in a vibration force field is set up.Based on Stokes assumption,the approximate analytical solution of Newtonian fluid velocity is obtained.The three dimensional numerical trace simulation of the dynamic mixing processing is carried out by fourth order adaptive Runge-Kutta scheme to characterize the dynamic mixing,and the pattern transformations of the tracer with time and stretch rate of the interfaces are demonstrated.The results show that no chaos occurs in the channel,the processing remains regulary laminar as the screw frequency is lower.The corresponding measures are suggested to improve the mixing effects.更多还原