Abstract: We present the results of a combined experimental and theoretical investigation of the vertical impact of low-density spheres on a watersurface. Particular attention is given to characterizing the sphere dynamics and the influence of its deceleration on the shape of the resulting air cavity. A theoretical model is developed which yields [...]

Water-entry of Spinning Spheres Abstract: The complex hydrodynamics of water entry by a spinning sphere are investigated experimentally for low Froude numbers. Standard billiard balls are shot down at the free surface with controlled spin around one horizontal axis. High-speed digital video sequences reveal unique hydrodynamic phenomena which vary with spin rate [...]