Raindrops splash before they hit the ground

2019-03-08 10:14:01

WHEN does a raindrop splash? Surprisingly, the process begins before it makes contact. A liquid drop hitting a surface often flattens into a thin sheet that then bounces to form a crown shape. Previous experiments have suggested the surrounding air plays a role: a droplet doesn’t splash so easily when the air pressure is low, instead spreading out into a thin pancake. Shreyas Mandre of Harvard University and colleagues ran computer simulations of liquid drops hitting a solid surface,