Abstract：
Superhydrophobic surfaces hold immense potential in underwater drag reduction. However, as the Reynolds number increases, the drag reduction rate decreases, and it may even lead to a drag increase. The reason lies in the collapse of the air mattress. To address this issue, this paper develops a pyramid-shaped robust superhydrophobic surface with wedged microgrooves, which exhibits a high gas fraction when immersed underwater and good ability to achieve complete spreading and recovery of the air mattress through air replenishment in the case of collapse of the air mattress. Pressure drop tests in a water tunnel confirm that with continuous air injection, the drag reduction reaches 64.8% in laminar flow conditions, substantially greater than 38.4% in the case without air injection, and can achieve 50.8% drag reduction in turbulent flow. This result highlights the potential applications of superhydrophobic surfaces with air mattress recovery for drag reduction.
摘要：
超疏水表面在水下减阻方面具有巨大潜力。然而,随着雷诺数的增加,减阻率降低，甚至可能导致阻力增加。原因在于空气床垫的崩溃。为了解决这个问题，本文开发了具有楔形微槽的金字塔形鲁棒超疏水表面，其在浸没在水下时表现出高气体分数,并且在充气床垫塌陷的情况下通过空气补充实现充气床垫的完全铺展和恢复的良好能力。在水隧道中进行的压降测试证实，在连续注气的情况下，在层流条件下减阻达到64.8%，在没有空气注入的情况下，基本上大于38.4%，在湍流中可以实现50.8%的减阻。这一结果突出了超疏水表面与气垫恢复减阻的潜在应用。
