[AlphaDelta]

Hi,
I am creating a surface mesh for my wind turbine.
If I create the mesh by deactivating "CAD projection", it creates strange areas with coarse cells on the outside of the blade (figure 1), if instead if activated "CAD projection" creates coarse striped areas on the inside of the blade (figure 2 ).
Anyone know the reason?

[ping]

this is strange but the surface mesher will very occasionally create local fine patches for no logical reason but this is not what you have.
what does the surface mesh of the cad of the blade look like that is your input to the surface mesher and does its mesh match in some way what you see in those remeshed surface? maybe try re-tessellating the cad to a coarser or finer setting in parts.
i suggest you check these things - your cad might have multiple surfaces near each other; there are other surface near the blade that are affecting the meshing; turn off proximity and compatibility refinement;