Water collection and transport in bioinspired nested triangular patterns.

To address water shortages worldwide, proactive measures are needed to supplement the water supply. In arid regions, many plants and animals use fog or the moisture in air as a source of water. An important consideration for efficient water collection is to transport collected water droplets as rapidly as possible to storage/use before they are evaporated. Triangular geometry has been used for faster transport of water droplets. In the case of a triangular geometry, if a droplet is placed at its apex, the droplet is driven across the triangular region by the Laplace pressure gradient. However, the magnitude of the gradient decreases along the triangle. In this study, nested triangles were designed to provide a higher pressure gradient. Water condensation and transport studies were carried out on the nested pattern at a temperature below the dew point in ambient air. It was found that the nested pattern increases the droplet travel speed. This article is part of the theme issue 'Bioinspired materials and surfaces for green science and technology (part 3)'.