[aulia]

Hi everyone,

I'm currently trying to do a robust optimization for a transonic airfoil for my thesis, and I'd like to know how to vary a mach number (not setting the mach number as a fixed parameter)? And I would also like to know how can I set the fixed Cl mode on Su2?
Perhaps anybody here can help me? I would appreciate any helps/comments. Thank you so much in advance.

Aulia

[economon]

Dear Aulia,

Thanks for your question(s). At the moment, we do not directly allow for a multi-point type of optimization for the Mach number or for the AoA to be used as a design variable. You're certainly not the first to ask for these features, so I think that we will need to consider expanding some of these options in the near future.

In the meantime, I'll note that the compute_polar.py script that is shipped with the SU2 distribution contains a good example of how to script runs for different Mach numbers, and this could be a good place to start for the Mach variation. Additionally, you can enable the fixed C_L mode with the following options:

% Activate fixed lift mode (specify a CL instead of AoA, NO/YES)
FIXED_CL_MODE= NO
%
% Target coefficient of lift for fixed lift mode (0.0 by default)
TARGET_CL= 0.0
%
% Damping factor for fixed CL mode (0.1 by default)
DAMP_FIXED_CL= 0.1

Note that you may need to play with the damping factor in order to maintain convergence, and that in this scenario, the AoA is not directly considered a design variable during optimization.

Hope this helps,

Thomas D. Economon
SU2 lead developer

[aulia]

Dear Thomas,

Thank you so much for your answer! It does help me.
I've tried the fixed lift mode and gonna explore more about this feature.

Thank you once again.

Best regards,
Aulia Maharani Akbar