Wave Boundary Layer

Oral

1215 - Interactions Of Waves With Idealized High-Relief Bottom Roughness

Presenting Author(s)

• XY

  Xiao Yu, PhD

  Assistant Professor
  University of Florida

Additional Author #1(s)

• JR

  Johanna Rosman

  Research Associate Professor
  Institute of Marine Sciences, University of North Carolina at Chapel Hill

Additional Author #2(s)

• JH

  James Hench

  Associate Professor
  Duke University

Interactions between surface waves and high-relief bottom roughness were investigated using LES of oscillatory flow over idealized topography composed of an infinite array of hemispheres. Simulation results were analyzed using a spatially- and phase-averaged momentum budget to provide insight into how flow-topography interactions affect wave-driven oscillating flows. Flow dynamics strongly depended on Keulegan-Carpenter number. At low KC the inertial force dominated flow dynamics, form drag was small, and Reynolds and dispersive stresses were negligible. At higher KC, strong flow separation occurred, both drag and inertial forces were important. The dispersive stress was the main mechanism for vertical momentum transfer.