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A study of transonic buffet on the NASA Common Research Model at flight Reynolds numbers is presented. The ability of two different hybrid RANS/LES models as well as the URANS approach for resolving three-dimensional buffet motion was evaluated by means of spectral analysis. Automated Zonal DES and URANS simulations show similar results in terms of buffet frequency and spanwise propagation of buffet cells, whereas the Delayed Detached Eddy Simulation results indicate a strong interaction between flow separation and shock motion. The extracted characteristic frequencies which are associated with transonic buffet are located in a range of Sr = 0.2–0.65 for URANS and AZDES and are therefore in accordance with findings from related recent research. Furthermore, the simulation time series were investigated and a structure of spanwise moving buffet cells with varying convection speed and wavelength could be observed.

In this work, wake-tail plane interactions are investigated for a tandem wing configuration in buffet conditions using hybrid RANS/LES simulations with the Automated Zonal Detached Eddy Simulation (AZDES) method. The analyzed configuration consists of two untapered and unswept wing segments, representative of a wing-tail plane configuration. A suitable airfoil for the rear wing was selected based on a preliminary study using the MSES potential solver toolbox. The shock oscillation on the front wing segment and the development of its turbulent wake are characterized, including a spectral analysis of the pressure and velocity fluctuations in the wake and a modal analysis of the flow field applying Proper Orthogonal Decomposition (POD). The impact of the wake on the aerodynamics and loads of the rear wing segment is then studied, with a spectral analysis of its lift and surface pressure oscillations. Finally, the influence of the position and the incidence angle of the rear wing segment are investigated. For the considered flow conditions, 2D buffet is present on the front wing segment with a buffet frequency of f = 118.5 Hz or a Strouhal number of Sr = 0.0745. The characteristics of the wake behind the front wing segment vary strongly within the buffet cycle. During the downstream movement of the shock, the amount

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