Model Order Reduction for Unsteady Aerodynamic Applications

In this work a nonlinear model order reduction approach for unsteady aerodynamic applications is presented. It is based on Proper Orthogonal Decomposition (POD). Given a set of snapshots, which are solutions to the full order model, POD yields an optimal basis for representing reduced order solutions of the governing equations. The idea of the reduced order modeling approach in this work is to formulate each time step of the unsteady equations as a steady problem. This yields the so-called unsteady residual. The unsteady residual is then minimized in the space spanned by the POD basis vectors. As this space is of reduced size, the minimization problem is as well. (© 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)