A SIMPLE INVERSE ESTIMATION METHOD OF OFFSHORE WAVE CONDITION FOR QUASI-DEEPWATER WAVE

Abstract

 A spectrum of quasi-deepwater wave which is defined in deeper shallow water can be only obtained by calculating the deformation of offshore wave spectrum in shallow water. Therefore, to estimate design waves of harbor facilities for the quasi-deepwater wave, the inverse estimation of offshore wave condition which may require several repeated trials of calculation of wave transformations from offshore is necessary. Moreover, the estimation accuracy may depend on the bathymetry and the surrounded topography of the point of the quasi-deepwater wave.

 To support that, we propose a simple inverse estimation method of offshore wave height and direction for quasi-deepwater waves, while it is assumed that offshore wave period is not varied in shallow water. And, diagrams of both wave refraction coefficients and angles and wave diffraction coefficient and angles are newly drown to be applied in the proposal method. It is confirmed that the offshore wave parameters can be estimated by using this method with a few trials of estimation of wave transformations.