Plunging solitary wave and its interaction with a slender cylinder on a sloping beach

Abstract

Laboratory experiments were performed for solitary waves breaking on a constant slope. In the second set of experiments a vertical cylinder was installed on the slope, which was subject to the impact of a shoaling solitary wave. PIV was used to record the time history of free surface elevations, and temporal and spatial velocity variations in two fields of view (FOVs). A numerical model was also employed to simulate the three-dimensional wave–structure interaction problem. Filtered Navier–Stokes equations are solved numerically. The small scale eddies were modeled by the traditional Smagorinsky LES model and RNG LES model. The data-model comparisons were performed. The agreement is very good for the free surface elevations before breaking occurs. The laboratory wave appears to break slightly sooner than the numerically simulated wave. The comparisons for the normalized horizontal velocity profiles in the water column in both FOVs show excellent agreement. However, the magnitude of depth-averaged horizontal velocities for the numerical wave is roughly 10–15% higher than that of laboratory wave. The numerical model is used to illustrate the runup process of the solitary wave on the cylinder. The time history of wave force is also calculated and correlated to the free surface evolution.