On the collision of a rigid sphere with a deformable membrane in a viscous fluid

We analyse the model problem of rigid, spherical pendula impacting on rubber membranes at different Reynolds numbers to understand the contact dynamics in deformable bodies in a viscous fluid. We have investigated the problem both by laboratory and numerical experiments and a new contact model has been developed to perform the simulations. We have found that the collision dynamics depends on many parameters, the most important ones being the impact Stokes number ( and this threshold increases as the membrane thickness decreases. Also, the membrane surface affects the dynamics of the impact by delaying the rebound for smaller membranes.