超疏水沟槽表面减阻特性数值模拟研究

A CFD Study on Turbulence Drag Reduction with Superhydrophobic Riblets

中文关键词: 湍流  大涡模拟  沟槽  超疏水

英文关键词: urbulence  large eddy simulation  riblets  superhydrophobic

中文摘要:

      沟槽结构和超疏水壁面可有效减小湍流流动阻力。 针对鲨鱼游动时表皮分泌黏液对鲨鱼表皮润湿性 的影响, 提出并研究具有更高减阻效果的超疏水沟槽结构。 采用雷诺时均法和大涡模拟分别分析两种沟槽结 构的减阻效果和机理。 结果表明: 未经疏水处理的刀刃形和锯齿形沟槽表面, 减阻效果最高分别可达9 .52% 及13.70% , 经超疏水处理后, 减阻效果最高可达58. 00% 和63. 00% , 其更小的湍流涡团及脉动是进一步减 阻原因。

英文摘要:

      The groove structure and superhydrophobic wall can effectively reduce the turbulent flow resistance. Considering the effect of the mucus secreted by a shark's epidermis on its wettability during swimming, a superhydrophobic groove structure with higher drag reduction effect is proposed and studied. Reynolds Averaged Navier-Stokes Equations (RANS) and Large Eddy Simulation (LES) are used to analyze the drag reduction effect and mechanism of the riblets structure. The results show that, without hydrophobic treatment, the drag reduction effect of the blade and sawtooth riblets surfaces can reach up to 9.52% and 13.70% respectively. After super-hydrophobic treatment, the drag reduction effect can escalate to 58.00% and 63.00% . Small turbulent vortex clusters and pulsations are the reason for the further drag reduction.