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Examples of orthogonal and curvi-linear netCDF files of models like Delft3D are available via:
http://coast-enviro.er.usgs.gov/thredds/catalog.html
The main difference between engineering type models like Delft3D and ocean type models available via that server is that Delft3D models are frequently using incomplete grids, i.e. structured grids that don't have (x,y) coordinate pairs defined for all grid index pairs. An example for the branches of the Rhine River in the Netherlands is shown below; the right figure shows the mask of the grid. A pdf of the full mesh including the mask can be downloaded ^curvigrid_missing_coords.pdf here. Because of the high degree of distortion in the grid (e.g. neighbouring grid lines may follow two separate river branches going off in two completely different directions), it's not possible to automatically generate reasonable coordinates for such masked points.
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