动波壁圆柱流场的数值模拟与减阻机理

Research on numerical simulation and drag reduction mechanism of fluid field of wavy wall circular cylinder

利用计算流体力学软件Fluent开展动波壁圆柱绕流的数值计算,建立二维运动波浪壁圆柱模型。在来流速度u=0.005 m/s、雷诺数Re=500的情况下,开展动波壁波动速度c=0,0.005,0.01,0.015,0.02,0.025,0.03,0.04 m/s等8个工况的计算分析,并比较不同波动速度对流场结构、升力、阻力特性的影响。结果表明:动波壁圆柱能有效抑制流动的分离,消除交替脱落的尾涡,减阻效果突出;随着波动速度的增大,平均阻力系数呈明显下降趋势;当波速超过0.025 m/s时,阻力变为负值,即波动圆柱产生一定的推力。

This article based on CFD software Fluent,developed the numerical calculation of wavy wall circular cylinder and established the model of the two DOF wavy wall circular cylinder. Under the of same inflow velocity u,Reynolds number Re and different fluctuation velocities where u = 0. 005 m /s,Re =500 and c = 0,0. 005,0. 01,0. 015,0. 02,0. 025,0. 03,0. 04 m /s,the paper developed the computational analysis of wavy wall circular cylinder. Furthermore,the paper compared the influence of flow field structure,the lift and drag characteristics under different fluctuation velocities. The results show that wavy wall cylinder can suppress flow separation effectively and eliminate the alternate shedding trailing vortex. The drag reduction effect is remarkable. The average drag coefficient is decreased obviously with the increased fluctuation velocity. When the wave velocity exceed 0. 025 m /s,resistance turn to negative. Then the wavy wall circular cylinder generate thrust.