FLOW PAST A ROW OF FLAT PLATES AT LARGE REYNOLDS-NUMBERS

The steady, incompressible, high Reynolds number, viscous flow past a row of flat plates is computed by a Galerkin finite element discretization of the Navier-Stokes equations in the stream function/vorticity formulation. A novel implementation of the inflow and outflow boundary conditions is described, which combines numerical stability with computational economy in the solution procedure. The calculations reported here cover the range of medium and small blockage ratios, i.e. 5 less-than-or-equal-to a less-than-or-equal-to 25 (where a is the inverse blockage ratio). A transition is found from narrow wake eddies for small values of a, to wide wake eddies for values of a above a(crit) almost-equal-to 15. This transition is in general agreement with the trends reported earlier by Fornberg (1991), for the related problem of flow past a row of circular cylinders (for which a(crit) was approximately 8).