Second Order Adaptive Boundary Conditions for Exterior Flow Problems: Non-Symmetric Stationary Flows in Two Dimensions

摘要: We consider the problem of solving numerically stationary incompressible Navier–Stokes equations in an exterior domain two dimensions. For numerical purposes we truncate to a finite sub-domain, which leads finding so called “artificial boundary conditions” replace conditions at infinity. To solve this construct – by combining results from dynamical systems theory with matched asymptotic expansion techniques based on old ideas Goldstein and Van Dyke smooth divergence free vector field depending explicitly drag lift describing solution second dominant third order, asymptotically large distances body. The resulting expression appears be new, even formal level. This improves method introduced authors previous paper generalizes it non-symmetric flows. scheme determines forces body self-consistent way as integral part process. When compared our where first order expressions were used boundary, inclusion terms further reduces computational cost for determining given precision typically another magnitude.