摘要
在半圆形管道中,周期振荡的压力梯度驱动不可压粘性牛顿流体的流动,运用分离变量法求解了半圆形管道内N-S(Navier-Stokes)方程,得到了速度解析解.在此基础上,我们研究了无量纲压强梯度有关的参数A和震荡雷诺数Re对速度剖面f的影响.结果说明速度振幅随参数A减少而减少,随Re减少而增加,而且出现脉动流速度的"环形效应".
A periodic oscillatory pressure-driven flow of viscous incompressible Newtonian fluid is studied.The Navier-Stokes equation is solved by using the method of separation of variables. Based on this,the effects of the nondimensional parameters,such as parameter A and Reynolds number Re regarding pressure gradient,on the velocity are investigated. The results show that the velocity amplitude decreases with A and increases with the decrease in Re. In addition, " toroidal effect" of oscillatory velocity is observed.
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