Research on Fast Aeroelastic Modeling Methods for the Transonic Regime

Two methods for modeling unsteady transonic flows at low computational cost are presented as a first step towards a fast and accurate aeroelastic calculation methodology for the preliminary design stage in the transonic flow regime. The first approach corresponds to a quasi-steady approximation based on few steady simulations that is improved through the use of an unsteady filter. The second approach is based on the interpolation of dynamic modes between solutions at different frequencies that are obtained either from Dynamic Mode Decomposition (DMD) of unsteady simulations or directly from Harmonic Balance (HB) simulations. The two methods are illustrated in the case of a pitching airfoil in the transonic regime. Results show that the first method is fast and provides a first approximation of the unsteady dynamics. The computational cost of the second approach is higher, but the method provides better results in predicting aerodynamic forces and shock motion for a large range of reduced frequencies.