Progress in Automatic Viscous Mesh Generation From CAD Using Strand/Cartesian Meshes

This paper discusses progress in automated viscous meshing capabilities using the StrandCartesian dual mesh paradigm. The RANS strand solver presented in earlier work has been extended to include the S-A turbulence model, with validations presented. A new strand grid generation approach is discussed which applies multiple strands emitted directly from a “solid” Boundary Representation (BRep), with multiple strands fanning out at geometric edges and nodes. The multi-strand grids avoid poorly shaped prisms that can arise at sharp convex corners and saddle points with the traditional bent strand approach traditionally used for strand grid generation. Sample 2D calculations using the new multi-strand approach compare favorably to calculations with traditional bent strands for high-Re RANS-SA calculations.

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