Skimming impacts and rebounds on shallow liquid layers

Abstract

The evolution of the combined solid–fluid motion when a solid body undergoes a skimming impact with (and rebounds from) a shallow liquid layer is investigated. A model is derived coupling the motion of the body to the fluid dynamics of the liquid layer. This predicts that the lift on the body induced by the pressure in the liquid layer is sufficient to entirely retard its incident downward motion before causing the body to rise out of the liquid. Water exit is predicted at a finite scaled time. Analysis for the small-time behaviour immediately after touchdown, and also as water exit is approached, shows close agreement with numerical prediction.