Instead of using a smooth surface, the team scored it with a series of skewed triangular grooves. This gives it a kind of saw-tooth profile. Now the water droplets appear to push themselves off the long-slope side of the grooves and rocket across the heated surface - instead of just dancing on the spot as they do in the kitchen pan. Droplets can also climb over steps, and up inclines of up to 12 degrees. Filmed with high-speed cameras, the droplets appear to take on a life of their own, sliding along like sloppy amoebae.
01 May 2006
Smarter Than You
Physicists have made water run uphill quite literally under its own steam.