| Summary: | Uniform barotropic flow past an island on the beta plane is considered. The equations of motion contain terms for horizontal diffusion of momentum, the beta effect, and non-linear advection of momentum. A vorticity equation is formed and put into finite difference form utilizing centered differences in space and time. The DuFort-Frankel scheme is used for the lateral diffusion of vorticity terms, and the resulting system of finite difference equations are solved using the Gauss-Seidel method with successive over-relaxation. A condition that the island boundary be a streamline is imposed as well as the requirement that there be no tangential velocity component on the island boundary. Three cases are considered; the generation of von Karman wake, the generation of Rossby wake and the combination of the two. In the first case, the characteristics of the von Karman wake over a range of Reynolds numbers are found to agree with those available from theory and experimental results. In the second case, the Rossby wake is found to exist over a range of Island numbers from 0.4 to 3.5. Increasing the Island number increases the amplitude and decreases the wavelength of the stationary wave. A combination of both wakes is found for a low Island number (0.4) and a high Reynolds number (480). Other combinations yield a Rossby wake damped by frictional effects.
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