I have been trying to model a shark inspired riblet surface on an airfoil NACA 6904, however, since the surface of the airfoil is non planar, I have problems when extruding the riblet´s profile.
This is the profile of the riblet surface:
and I attached the airfoil model in which I want to extrude it.
It is important to mention that I only want to extrude the riblet on the upper surface of the airfoil.
I hope you can help me I would be very thankful.