Control of drop rebound with solid target motion

Abstract

Drops with a high surface tension and a low viscosity, such as water and molten metal drops, exhibit a vigorous recoiling and a long-lasting oscillation upon impacting with nonwetting solid surfaces. Here we report a scheme of controlling drop rebound using target movement, without resorting to chemical modification of either drop liquid or solid surface. Our experimental study reveals that drop rebound is promoted when the target moves upward at the moment of impact. On the other hand, an effective suppression of drop rebound is achieved by moving the target downward upon drop impact. It is shown that these modifications in drop rebound behavior are not due to the drop impact speed change. Furthermore, a properly timed reversal of the target's moving direction is shown to control drop rebound more effectively than the monotonous target motions. (C) 2004 American Institute of Physics.