FUN3D v12.4 Training Session 14: Adjoint-Based Design for Unsteady Flows

The Challenges of Unsteady Adjoint-Based Design:
- The adjoint approach still provides all of the sensitivities at the same
cost as analysis, and the 20x estimate still applies for the expense
of an optimization
- But every simulation is now an unsteady problem
- Where the steady adjoint solver linearized about a single solution
(the steady-state), the unsteady adjoint solver must essentially do
this at every physical time step