Low Cl and Cd for a simple subsonic wing
 

Hey guys! I was wondering if anyone might have some time to help me figure this out: I am trying to simulate a flow of 10m/s on a symmetric model of a wing, with a dihedral of 5 degrees at its halfway point (the whole wing is 3m, but the symmetric model I created is just 1.5m long). I ran both viscous and inviscid simulations on SU2, and both yielded really low values for Cl (Cl = 0.081 for the viscous and Cl = 0.207 for the inviscid simulation). Cd was also quite low (around 0.02 to 0.09).

I have tried increasing the distance from my wing to the wall, and also included a much denser mesh, but the results have not varied by much (in this case, Cl became 0.241 in the inviscid simulation).

If you would kindly check, I have attached my cfg files down below, as well as a picture of my setup. Any useful information/advice as to why this is happening would be much appreciated, as I am a little new to SU2!

Because the mesh files were too big to include, I am just describing them here:
- The mesh for the inviscid simulation had markers for the upper and lower surface of the wing, the tip of the wing, the symmetry face, and for the pairs of opposite sides of the box (front and back surfaces, above and below surfaces, and the side of the box opposite to the wing)

- The mesh for the viscous simulations had markers for the wing surface as a whole, the symmetry face, and the farfield (all the other sides of the box).

- The box is 20m by 20m.

Thank you so much!!:)

Hello!

Thanks for using SU2! Without your mesh file it is hard to say. I have little experience in low speed wings, especially at 10 m/s.

My advice would be to check a single segment of the wing. You could also look at the pressure profiles around the wing.

Lastly, at this speed, you could possibly try the incompressible solver.

I hope this helps!

Wally