The Lotus, the pitcher, and the fish
Nature's solutions to sticky problems.
In Nature, living organisms face endless 'sticky' wetting problems — and overcoming them is often a matter of life and death. Insects must avoid getting trapped by falling raindrops, and plants need to keep their leaves dry for efficient gas exchange through its stomata, or they will literally suffocate to death.
Necessity is the mother of all inventions, and Nature, through evolution, has developed a whole suite of strategies to keep unwanted material, be it liquid or micro-organisms, from sticking to their surfaces.
Inspired by examples in Nature, notably the lotus plant, the pitcher plant, the fish scale, and articular cartilage in joints, I seek to understand and engineer surfaces to repel a wide range of liquids, as well as fouling organisms, such as bacteria.
Leonardo da Vinci
Bouncing jets and rolling drops
More generally, I am fascinated by fundamental interfacial and fluid mechanics phenomena. Why do raindrops wick quickly into our shirt, but remain as hemispherical droplets on a raincoat?