SPH Validation of Momentum and Energy Flux of an Oscillating Horizontal Cylinder Near Free Surface*

In this talk we present a two-dimensional control volume SPH formulation analysis of a neutrally buoyant horizontal slender circular cylinder with diameter D=0.27m. Cylinder is fully submerged below the free water surface with the major axis aligned in the direction perpendicular to the incident wave propagation. SPH results are validated against experimental data performed in a large (380ft) USNA towing tank. Talk will concentrate on the cylinder response and momentum/energy budget over incident wave energy spectrum in a range of wave steepness 0.02 < kA < 0.2 where k is the wavenumber, A is incident wave amplitude and wave periods from 0.8 to 2.2 seconds. Preliminary results suggest that SPH energy flux through the control volume matches experimental results at wave periods away from the resonance condition. At resonance, non-linear regimes characterized by localized increased wave steepness and wave breaking occur within control volume. Discussion will focus on how well the SPH resolves these non-linear behaviors.