Use of Phase-Resolving Numerical Wave Models in Coastal Areas
Abstract
The choice of a particular wave model for use in nearshore wave climate forecasting or hindcasting is usually contingent upon the site to be considered and the processes to be modeled. Phase averaged spectral models such as SWAN, WAM or STWAVE are source based energy models which treat the wave field as a stochastic phenomenon. This particular formulation allows for the consideration of wind wave generation, among other source terms. These models (particularly STWAVE and SWAN) are able to simulate irregular wave propagation over coastal areas relatively efficiently; however, the propagation terms in these models are derived from ray theory and do not handle bathymetrically induced diffraction, which may be important in coastal areas. (It should be noted that STWAVE does not contain some accounting for diffraction as a diffusion of wave energy in the source terms). Phase resolving models such as REF/DIF1, REF/DIF-S and RCPWAVE by contrast, treat the wave field deterministically, tracing the free surface evolution over the domain. The irregular nature of the wave field can be accounted for by running several wave frequencies/directions through the model and calculating the statistics from the model results. This is often done by discretizing an input spectrum into frequency and direction bins, calculating the waveheight in each bin and then running them through the model. This formulation is most useful in the case of complex bathymetry and predominantly swell like conditions. Models in this latter class cannot account for wind wave generation.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1998
- Accession Number
- ADA337813
Entities
People
- Erick Erick Rogers
- James Kaihatu
- William C. O’reilly
- Y. Larry Hsu
Organizations
- United States Naval Research Laboratory