Bioinspired microgroove arrays with drag reduction and hydrophobic properties

Reducing energy consumption is one of the most effective ways to solve the problem of energy shortage. In this work, nature-inspired paint microgroove arrays with different periods were fabricated using a one-step laser ablation method. A wind tunnel experiment was performed at two wind speeds, 27.7 and 33.3 m/s, to collect drag force data on smooth and structured paint coatings. The results showed that microgroove arrays oriented perpendicular to the flow direction were beneficial to drag reduction, and a drag reduction rate of up to 7.2% was obtained. Meanwhile, the microgroove arrays induced by laser ablation changed the wettability of the paint surface to hydrophobicity. The contact angle shows a slightly decreasing trend with an increase in the periodic scale. Furthermore, the anticorrosion properties of these microgrooves make them advantageous in harsh environments. The fabricated drag-reducing paint microstructures, with the features of self-cleaning and durability, have the potential to be applied on vehicles to realize speed improvement and energy saving.