[Luca B]

Hi, i'm doing the optimization of a multi element airfoil with the FFD method. I leave the trailing edge of the main profile out of the box, and for guarantee the deformation continuity i increase the SHARP_EDGE_COEFF. This works well, but i want to know if there is documentation about this option. I'm writing my graduation thesis on the SU2 shape optimization and i want to explain better the function of this parameter. Thank you in advance.

[awendorff]

SHARP_EDGE_COEFF is usually used for removing sensitivity at sharp edges that are used in mesh deformation or limiting in the numerical methods. It is not usually used for deformation continuity. The FFD deformation follows the typical structure with minor variations for best practices. These best practices are not summarized in a formalized document.

[hlk]

Originally Posted by Luca B

Hi, i'm doing the optimization of a multi element airfoil with the FFD method. I leave the trailing edge of the main profile out of the box, and for guarantee the deformation continuity i increase the SHARP_EDGE_COEFF. This works well, but i want to know if there is documentation about this option. I'm writing my graduation thesis on the SU2 shape optimization and i want to explain better the function of this parameter. Thank you in advance.

In addition to the good information Andrew stated; I would recommend looking at the "FFD_CONTINUITY" setting which controls whether the surface tries to be 1st or 2nd order continuous at the edge of the FFD box.
In the code this setting is used in:
CSurfaceMovement::CheckFFDIntersections
(grid_movement_structure.cpp)