Modelling of electromagnetic wakes of moving submerged bodies in stratified sea water

Moving submerged bodies create wakes behind them. The motion of the sea water, because of its conductivity, induces an electromagnetic perturbation (b/spl I.oarr/, e/spl I.oarr/) in the Earth magnetic field B/spl I.oarr//sub T/. In this paper, we propose a numerical modelling of this perturbation. The water velocity field V(x,y,z) is first computed in two different cases: turbulent wake obtained using a finite volume method, wave field by a perturbation method. Then, the corresponding electromagnetic perturbation is obtained by solving the Maxwell equations including the Lorentz term. For that, we use a finite element method.