Effect of large material elasticity on water skipping physics of deformable spheres

Water skipping has attracted significant focus in fluid dynamics, with extensive research on rigid bodies contrasting with limited exploration into the dynamics of elastomeric bodies. At low impact Froude numbers, the effect of large material elasticity on water skipping physics of deformable spheres is investigated. The result shows that the deformability of elastic spheres enhances the ability to skip on the water surface compared to rigid spheres. The improved skipping is attributed to the internal responses induced by the deformation behavior and increased wetted area of sphere. Elastic spheres demonstrate asymmetrical cavity formations and periodic deformation patterns during water skipping. The impact dynamics of skipping spheres are investigated, revealing that the inflection point in the velocity curve of the skipping sphere depends on the deformation behavior. Additionally, the time histories of wetted areas are classified into four distinct stages, varying depending on the density and shear modulus of the sphere. Furthermore, an optimal impact duration for enhancing skipping efficiency of elastic spheres is determined, characterized by an inverted parabolic relationship.