Wing twist optimization using mesh deformation
 

Hi everyone,

I would like to optimize the twist distribution of a rectangular wing in SU2. The cross sectional shape must remain the same.

Does anyone know how I could do this using mesh deformation? I cannot get FFD_TWIST_ANGLE to do what I want it to. FFD_ROTATION seems a little better since it does not warp the cross sectional shape, but I can't get that to work properly either. I have thought about using FFD_CONTROL_POINT too, which I know how to use. However, I thought this might warp the cross sectional shape.

What I have been trying seems to give the whole FFD box a constant twist angle. I instead want to apply a continuous distribution (in discrete sections perhaps? that part I am not sure about). If I use multiple DV_PARAM values at different ranges of z then the entire wing just twists/rotates it to the sum of the angles.

Here are the important parts of the .cfg file I have been using to deform the mesh. In this case I was just trying to understand how to control it by twisting the last 0.5m of the wing upwards by 10 degrees (about the trailing edge, (x,y)=(1,0)). How quickly it twists doesn't matter in this case since I was just trying to get a feel for how it works.



DV_PARAM = ( wing, 1.0, 0.0, 2.5, 1.0, 0.0, 3.08 )
DV_VALUE = 10.0

% FFD box definition for a wing of unit chord and wingspan of 3:
FFD_DEFINITION= (wing, -0.1, -0.08, -0.08, 1.1, -0.08, -0.08, 1.1, 0.08, -0.08, -0.1, 0.08, -0.08, -0.1, -0.08, 3.08, 1.1, -0.08, 3.08, 1.1, 0.08, 3.08, -0.1, 0.08, 3.08)

% divide the box into 10 sections along Z direction:
FFD_DEGREE= (1, 1, 10)



I don't think this related, but this is the command I use to deform it:
SU2_DEF inv_Rectangular_wing.cfg



Any tips, suggestions, explanations, links to other forum posts, etc. are greatly appreciated. Thanks!