Stephan T. Grilli
Distinguished Professor
Department of Ocean Eng.
University of Rhode Island
Narragansett, RI 02882, USA
Abstract :
Two Depth Inversion Algorithms (DIAs) were developed and
validated using on results of computations for the shoaling of periodic
waves over mild slopes, in a two-dimensional numerical wave tank, based on
fully nonlinear potential flow theory.
The first algorithm, DIA1, uses sets of values of wave celerity c, height
H, and spatial wavelengths Lc and Lt, simultaneously measured at a number
of locations xi (i=1,...,N) in the direction of wave propagation (e.g.,
using remote sensing techniques), to predict the depth variation h(xi).
The second algorithm, DIA2, uses spatial wave asymmetry s2/s1 calculated
from wave phase, instead of H.
Results indicate that state-of-the-art depth inversion methods based on
the linear dispersion relation may lead to large errors (50-70%) for the
depth prediction in very shallow water, whereas the present methods are
3-10 times more accurate.
Keywords :
Wave propagation, nonlinear wave models, shallow water, numerical methods, inverse modeling, depth prediction, coastal engineering.