A photographic technique for investigating the splashing of water drops on leaves

Abstract

The formation of splash from water drops falling onto bean leaves was investigated by multiple exposure flash photography. A relatively simple technique was developed which recorded up to four images at 2 ms intervals, of a splash on one photograph. The images were recorded on colour reversal film, and the flash sequence was colour coded to aid the interpretion of the superimposed images. Analysis of the photographs allowed measurement of the initial speed and angle of ejection of different sized splash droplets. Droplets were ejected at speeds of up to about 10 m s‐1although most speeds were less than about 3 m s‐1, and small droplets tended to travel faster than large ones. Droplets were ejected at all angles but the majority were ejected almost horizontally; there was little correlation between droplet size and angle of ejection. Deposition patterns estimated from calculated droplet trajectories compared well with measured ones. Copyright © 1988, Wiley Blackwell. All rights reserved