A BIDOMAIN PRIMITIVE EQUATION MODEL

This study concerns numerical simulations carried out following the el aboration of an oceanological multidomain model. These simulations dem onstrate the value of such a model for physical oceanography. A simpli fied, two-domain version of the multidomain model is presented. It is based on a computer code which solves the Navier-Stokes and temperatur e equations in the three dimensions of space for an incompressible flu id in accordance with the hydrostatic approximation and Boussinesq's a ssumption. This model permits a zoom on a specific region of the spati al domain, where the primitive equations are solved, with a mesh refin ement, in order to correct by feedback the global numerical solution. It includes a nested procedure which manages the resolution of the dif ferential problem on two domains. This technique of domain decompositi on forms part of the numerical methods of domain refinement with full overlapping. The model is tested by the simulation of a barotropic mod on, an analytic solution, of the quasigeostrophic potential vorticity equation, adequately representative of an oceanic vortex. The numerica l solutions obtained with the monodomain and bidomain model are compar ed with each other by calculation of the errors commited in the two ca ses relative to the analytic solution. It appears that this interactiv e nested technique permits correct management of open boundaries condi tions. The zoom performed on a region of the spatial domain efficientl y corrects the global solution compared with that obtained by the basi c monodomain model.