AeroDyn driver force node mapping end point mismatch

[kevmoor]

OWENS side, looking at the Fxh, Fyh, Fzh (overall force in the hub frame), we’re spot on, but we still have the ~2% difference when I try to pick out the individual blade global loads. I’m guessing this has something to do with the mesh mapping of overlapping nodes, which we identified before as likely being a non-issue for the aeroelastic simulations and reaction loads/strains, but an issue for component load verification like we are doing here.

From OpenFAST side:
The current implementation in the ADI library uses a single mesh of points to represent the OWENS structural mesh. Internally the ADI library has a different mesh for each blade. So when ADI performs the mapping of the blade mesh loads over to the OWENS point mesh, it may misplace the end node of a strut onto the closest node of a vertical blade. To correct this might require either some additional logic in the ADI meshing, or passing multiple meshes across from OWENS – both of these options could get a bit more involved.

[kevmoor]

This was fixed on the OpenFAST side, and will be released with OpenFAST v4.0