If anisotropic mesh adaptation has been a reliable tool to predict inviscid flows, its use with viscous flows at high Reynolds number remains a tedious task. Indeed many issues tends to limit the efficiency of standard remeshing algorithms based on local modifications. First, the high Reynolds number require to handle a very high level of anisotropy O(1 : 10~6) near the geometry. In the range of anisotropy, interpolation of metric fields or the projection on geometry are typical components that may fail during an adaptive step. The need for high-resolution near the geometry imposes to use an accurate geometry description, and optimally, be linked to a continuous CAD geometries. However, the boundary layer sizing may become smaller than typical CAD tolerance. We present a simple hierarchical geometry approximation where the newly created points are projected linearly, then using a cubic approximation then the CAD data. Finally, the accuracy, speed of convergence of the flow solver highly depends on the topology of the grids. Typical quasi-structured grids are preferred in the boundary layer while this kind of grids are complicated to generate with typical anisotropic meshing algorithm. We discuss in this paper, new developments in metric-orthogonal approach where an advancing points techniques is used to propose new points. Then these newly created points are inserted by using the cavity operator.
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