Hydrodynamic loads during water entry of two- dimensional and axisymmetric bodies

In this paper the free-surface flow generated by the vertical water entry of two-dimensional symmetric and axisymmetric bodies of arbitrary shape is numerically investigated. The study is carried out in the framework of potential flow of an incompressible fluid with gravity and surface tension effects also neglected. The unsteady flow is computed through a boundary-element formulation and nonlinearities in the free-surface boundary conditions are fully retained. Attention is mainly focused on evaluating the pressure distribution and the total hydrodynamic load acting on the impacting body. For validation, the approach is applied to the water impact of a cone with constant entry velocity, and checks of the self-similarity of the solution are made. Next, the water impact of a circular cylinder and of a sphere are analyzed. Comparisons with available theoretical solutions and experimental data are made.