Flow-Field and Induced Bed Shear Stress Due to a Sphere Oscillating Close to a Boundary

The study of complex flow field problems concerning fully submerged structures of spherical shape oscillating adjacent to a solid boundary within the fluid is of immense importance due to their fundamental interest and high relevance to wave energy converters. This study investigates the flow field and shear modifications close to a plane boundary using three-dimensional direct numerical simulations and flow visualisation experiments. A novel particle congregation is demonstrated, towards which particles are swept and would accumulate over a long duration of operation of the oscillating object. This phenomenon will affect the positioning of mooring points and seabed environmental impacts.