Stephan T. Grilli and R. Subramanya
Associate Professor Graduate
student
Department of Ocean Eng. URI
niversity of Rhode Island
Narragansett, RI 02882, USA
Abstract :
Recent improvements to the fully nonlinear potential flow model
by Grilli et al. are presented in the areas of : (i) higher-order
free surface representation using the ``Mid Cubic Interpolation technique''
(ensuring continuity of both free surface slope and tangential gradient
of field variables); (ii) numerical methods for quasi-singular integrations
(an important problem for the computation of breaking waves in shallow
water in computational domains with large aspect ratio); (iii) corner representation,
continuity, and compatibility relationships (an important problem for wave
generation by a numerical wavemaker in the model); (iv) node regridding
and redistribution techniques (a necessary improvement for both resolving
details of breaker jets and compensating for the ``node drift'' in nonlinear
wave flows); (v) exact generation of nonlinear periodic (streamfunction)
waves with zero-net-flux in the model (necessary to provide ``clean'' incident
waves); and (vi) absorption of incident wave energy in the model with an
adaptively calibrated ``absorbing beach'' (necessary for running long term
computations of wave shoaling and breaking in shallow water).
Applications are presented for advanced nonlinear wave propagation problems that illustrate the newly improved features of the model.