Convert 2d, diagonalized, unstructured grid to structured -- CGNS
 

I have developed a C++ code for mesh adaptation (2d, structured). I read and write meshes using CGNS. We are currently using Fluent to run flow solves, but have discovered that Fluent exports the grid and data in an unstructured CGNS format. I have the initial grid in (structured) CGNS format (generated by Pointwise), and I need to find a way to convert the unstructured flow solve data back to the structured grid. The flow solve data is needed to control the adaptation.

I've spent a while in Fluent and CGNS docs, but can't seem to figure out how to do this. Basically, I need to know how the nodes are numbered (I think).

Any pointers or references are greatly appreciated.

Wound up doing a brute-force re-ordering by comparing x- and y-coordinates in the unstructured grid with the structured grid. Fixed all my issues.