The new direct action scheme is elaborated for approximation of two-dimensional Navier-Stokes equations on high cell aspect ratio (CAR) unstructured grids. This scheme employs the Voronoi cells as control volumes. For convective and viscous terms the scheme produces the conventional cross-type scheme on triangulated rectangular grids. The scheme approximates the additional integral representing the conservation of angular momentum. An accuracy of approximation of direct action scheme can be estimated by error functional specified at each grid point. This functional estimates the quality of unstructured grid for direct action scheme. The matrix dissipation is used for dumping odd-even instability of centered scheme. It combines the accuracy of upwind schemes with robustness and efficiency of centered ones. The construction of highly stretched Delaunay triangulations consists of two steps. At the first step nearly orthogonal structured high CAR grid is generated near bodies and wakes. At the second step this grid is smoothly continued inside the computational domain by incremental insertion technique. The calculation of turbulent viscous flows around single and multielement airfoils were performed by the presented method with Spalart-Allmaras one equation turbulence model incorporated in it.
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