Couette-Taylor-Poiseuille流的数值模拟

对中等半径比同心旋转圆柱间Couette-Taylor-Poiseu ille流进行了数值计算,并与已有的实验数据进行比较以获得流场的更多信息。结果表明,数值计算与实验结果吻合较好,依次再现了层流涡、波动涡、非波动螺旋涡以及波动螺旋涡;轴流可以起到稳定流场的作用,轴流存在时,流场转捩的临界泰勒数Ta值会变大,涡胞变小,涡心不再位于轴间隙的中间,从左向右的轴流比较明显,交替指向内轴和外轴,并缠绕在涡胞的周围;除去平均轴流速度后,速度矢量场显示出不同的涡形,形状与相同Ta时的涡胞基本相同;在不同的泰勒数Ta和雷诺数Re下,涡心的轴向传播速度约为平均轴向流速的1.17倍,相传播速度约为内筒转速的0.42倍。

Numerical Simulation of Couette-Taylor-Poiseuille Flow

Numerical simulation according to the experimental of Wereley and Lueptow was made to verify the experimental results and to further study detailed flow fields and bifurcations related to Taylor-Couette flow with axial flow.The result of the numerical simulation is highly consistent with the experiment and the vortices in various flow regimes including non-wavy laminar vortex,wavy vortex,non-wavy helical vortex and helical wavy vortex are all reproduced in accord with their experiments.The result of the simulation shows that the axial flow stabilizes the flow field.With the axial flow,the transition to Taylor vortex flow occurs at a higher Taylor number than with no axial flow.The vortices shrink and the vortex centers are no longer in the center of the gap.Velocity vector fields show the axial flow winding around vortices,and when the axially averaged axial velocity profile is removed from the velocity field in a medicinal plane,the velocity field looks much like it would with no imposed axial flow.Taylor vortices translate with the axial flow at a velocity of about 1.17 times the mean velocity of the axial flow;phase speed is almost constant at 0.42 times of angular velocity of the inner cylinder regardless of Taylor number Ta or Reynolds number Re.