This research seeks to model and elucidate the physics of water impact of elastomeric spheres, including the mechanisms by which severe deformations enable spheres to skip off the free water surface. The interplay between solid mechanics and fluid mechanics, or fluid-structure interaction, is extremely rich and complicated for this physical phenomenon. This research and knowledge could lead to exciting applications such as the novelty products from Waboba Inc. Numerical simulations are performed in Abaqus/Explicit of a highly-compliant elastomeric sphere impacting a free surface of water using a Coupled Euler-Lagrangian (CEL) approach. Here, the spheres are modeled using a non-linear hyperelastic constitutive law in a Lagrangian frame and the fluid flow is determined by numerically solving the Navier-Stokes equations in an Eulerian frame. In addition, rate dependent effects of the elastomer are included using a linear viscoelasticity model calibrated from dynamic experiments. For validation, the simulations are compared to experiments. The testing utilizes multiple high-speed cameras which capture the sphere kinematics and vibrational modes of deformation in addition to collision timescales and details of the shape of the cavity formed in the liquid. The influence of various conditions-such as mesh convergence and contact sensitivity-on simulation results will be discussed. In addition, several benchmarking results will be shown and physical insight will be drawn from the models to help better understand the basic physics of water-skipping spheres.
Modeling of Hyperelastic Water-Skipping Spheres using Abaqus/Explicit.
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