  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. 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. During the
downstream movement of the shock, the amount of separation reaches its minimum
and small vortices are present in the wake. During the upstream movement of the
shock, the amount of separation is at its maximum and larger turbulent
structures are present together with high fluctuation levels of velocity and
pressure. A distinct peak can be associated with the meandering motion of wake
vortices, identified by means of a modal analysis of the flow field using
Proper Orthogonal Decomposition. The impingement of the wake causes a strong
variation of the loading of the rear wing segment. A comparably low-frequent
oscillation of the lift coefficient, attributed to the change of intensity of
the downwash caused by the front segment, can be distinguished from
fluctuations of high frequency that are caused by the impingement of the
turbulent structures in the wake.
