Fidelity Pointwise Grid Cell Remediation Method for Overset Meshes
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For structured cells, where grid cell counts are fixed, an adaptive grid redistribution method based on the parametric solution
of the elliptic equations has been revisited and extended to the overset problem. For unstructured grids, vertex insertion
methods are used to refine the mesh, again to reduce the disparity in size between local and foreign cells. Each method
computes target lengths at existing mesh points, superimposes foreign cell edge lengths at interpolation locations, and then
smooths the values to propagate the foreign cell influence into the mesh.
Figure 1. Example Overset Mesh
Determination of Target Cell Size
Strong differences in mesh resolution at locations of solution communication between component grids can lead to grid
assembly failure (orphans) and solution accuracy reduction. The goal is to match mesh resolution in local and foreign grids at
points of communication. The remediation methods described below require a target length scale at each vertex in the local
mesh. Smoothing of the target length scale will be used to minimize changes to grid quality. Finally, the target length scale
should be determined automatically from the composite grid assembly data.
Figure 2. Target edge length determination
