Numéro : 1931 - Year : 1983
Diffraction-radiation in presence of a current
A.GREKAS, Docteur Ingénieur ALSTHOM-ATLANTIQUE ACB
G. DELHOMMEAU, Docteur-Ingénieur ENSM de Nantes
Seakeeping in presence of a current is a problem of actuality.
As the physical problem is very complex, its study can only be taken up in using simplifying assumptions; the most important of them still remains that of linearization.
In this paper we propose a simplified 3D model of diffraction-radiation in presence of a current so as to answer the problem raised as simply as possible in order to satisfy the engineering needs without so wandering from the specific hydrodynamic aspects.
The basic idea is to rule out from the free linearized surface condition, the terms which depend on the current speed square, as this speed is low.
The other boundary conditions are worked out in a classical manner, and so we avoid to formulate restrictions on the hull shapes.
The diffraction and radiation potentials are solved by using a superficial distribution of Kelvin pulsating sources, the expression of which we define by introduction of the almost perfect fluid concept. Finally, we present some of our numerical results.