Pyramid-Shaped Superhydrophobic Surfaces for Underwater Drag Reduction

作者：Liangpei Zhang, X. Wan, Xu Zhou, Yanlin Cao, Huiling Duan, Jiale Yan, Hongyuan Li, Pengyu Lv · 发表于：ACS Applied Materials & Interfaces · 年份：2024 · DOI：10.1021/acsami.4c09631 · 被引用次数：31 · 研究领域：Surface Modification and Superhydrophobicity、Fluid Dynamics and Heat Transfer、Aerosol Filtration and Electrostatic Precipitation

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.