Recently two numerical spectral methods, based on the use of the Fast Fourier Transform. algorithm, have been found to be useful for studying the statistical properties of a large number of interacting random waves: the first one is known as the Higher Order Spectral (HOS) method and the second is based on the computation of the dynamical equation arising from the Hamiltonian description of surface gravity waves. Here we show analytically the relation between these two methods; more in particular, starting from the HOS approach and writing the corresponding evolution equations in spectral space, after a proper symmetrization of the coupling coefficients in the resulting integral terms, the Hamiltonian dynamical equations are recovered.
On the relation between two numerical model methods for the computation of random surface gravity waves
ONORATO, Miguel;OSBORNE, Alfred Richard;SERIO, Marina
2007-01-01
Abstract
Recently two numerical spectral methods, based on the use of the Fast Fourier Transform. algorithm, have been found to be useful for studying the statistical properties of a large number of interacting random waves: the first one is known as the Higher Order Spectral (HOS) method and the second is based on the computation of the dynamical equation arising from the Hamiltonian description of surface gravity waves. Here we show analytically the relation between these two methods; more in particular, starting from the HOS approach and writing the corresponding evolution equations in spectral space, after a proper symmetrization of the coupling coefficients in the resulting integral terms, the Hamiltonian dynamical equations are recovered.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.