Coastal engineering is the study of the processes ongoing at the shoreline and construction within the coastal zone. The field involves aspects of near shore oceanography, marine geology, and civil engineering, often directed at combating erosion of coasts or providing navigational access.
Modeling Wave Propagation
Waves, generated primarily by the wind, propagate from the ocean to the shoreline across the continental shelves. These waves undergo many processes before they dissipate in the surf zone: refraction, diffraction, shoaling, and breaking. The energy and momentum associated with the waves arriving at the surf zone is used to create longshore and cross-shore currents that move the sand comprising beaches. This sand transport, if it carries more sand away from a site than towards it, results in beach erosion. Read more about FLOW-3D's wave generation modeling capabilities.
FLOW-3D simulates the introduction of a true Stokes wave at the boundary
produces the correct wave profile as the wave breaks on the beach.
Maintaining conformation to the correct wave provides engineers with
force distributions and breaking distances to develop coastal structures.
Simulating Coastal Erosion
The processes of coastal erosion are very complex, involving three-dimensional flow fields created by the breaking waves, unsteady turbulent sediment transport in both the water column and on the bottom, and a moving shoreline. Research is being conducted worldwide to develop predictive models of this erosion process.
FLOW-3D's General Moving Object model can be used to evaluate the effectiveness of various designs for damping or altering wave frequency. The animation below depicts incoming waves interaction with a semi-buoyant device. The wave momentum is transferred into the device thus decreasing the outgoing wave amplitude.
A wave damping simulation with FLOW-3D. Courtesy of Narvik Institute of Technology.