SU2 Discrete adjoint skips optimization iterations
 

I have been trying to perform an unconstrained aerodynamic optimization of a BWB using SU2 Descrete Adjoint Optimization. I have noticed that the adjoint was calculated for the first 3 iterations, then it was not calculated for the 4th one, then it was solved again and then stopped being solved completely. Could you tell me what could cause such behavior and if it is normal.

Thank you,
Stan

Yes, it is possible. When adjoint solver is called this means optimizer needs gradients of design variables, when it is not called optimizer simply do line search to decide new stepsize. in this case only flow solution is enough.

atelcikti1,
Thank you very much! it make sense now

I have one more question. At some point the optimizer stops making adjoint iterations and the drag stops reducing. However, the solution keeps going. Does it mean I am converged because I see some deformations of the geometry but no effect on drag?