Bio-inspired 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, the nature-inspired paint microgroove arrays with different periods were fabricated using a one-step laser ablation method. The wind tunnel experiment was performed at two wind speeds 27.7 m/s and 33.  m/s to collect the drag force data on smooth and structured paint coatings. The results shown that the microgroove arrays oriented perpendicular to the flow direction were beneficial to drag reduction, and the drag reduction rate of up to 7.2% was obtained. Meanwhile, the microgroove arrays induced by laser ablation changes the wettability of paint surface to hydrophobicity. The contact angle (CA) shows a slightly decrease trend with the increase of the periodic scale. Besides, 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.