中文摘要：

利用ANSYS—FLOTRAN有限元分析软件模拟了不同振动频率下圆管内不可压缩幂律流体非定常流动的速度场。结果表明：1）振动力场作用使熔体在人口附近出现速度突变，振动频率越高，突变越厉害，速度值越大，稳定时圆管的无量纲长度越大；2）熔体轴向速度在径向呈类抛物线分布，振动频率存在最佳值，大于或小于最佳振动频率，熔体轴向速度分布范围均会变宽，流动变得不稳定；3）出口处速度响应存在时间延迟和速度峰，随着振动频率的增加，速度峰值升高，稳定时熔体轴向响应速度波动范围变宽，波动平衡点速度值升高。

英文摘要：

A numeric simulation of pulsating flow velocity field was proceeding with FEM software ANSYS-FLOTRAN for incompressible power law fluid in tube under different vibration frequencies. The results indicated that： 1 ） A abrupt of velocity occurred near the entrance and both the dimentionXess length of tube and velocity increased with frequency when the equilibrium was obtained. 2） Polymer melts exhibited parabolic velocity field in radial direction and the axial velocity range became wider as the flow became unsteady when the vibration frequency was far away from the optimal value. 3 ） The velocity response experienced a delay and velocity peak in the entrance, the velocity peak increased, the velocity range turned wider and the equilibrium velocity rose with the increase of vibration frequency.