Unsteady flow and interaction phenomena at High Speed Stall conditions

The studies include aerodynamic interactions with future Ultra High Bypass Ratio (UHBR) engine configurations and the impact of the wing wake on the horizontal tail plane (HTP). The phenomena will be investigated at Reynolds numbers relevant for aircraft in flight, with special emphasis on the boundaries of the flight envelope. For this purpose, unsteady experimental studies will be carried out in the European Transonic Wind Tunnel (ETW) in Cologne, applying the latest flow measurement techniques. This cryogenic wind tunnel enables recreating of flight-like Reynolds and Mach numbers on scale models of full aircraft configurations via extreme cooling of the flow medium.

Computational studies also form a large part of the investigations, with simulations conducted both at full aircraft level for global studies and at local detail level for precise predictions of physical effects. The methods comprise RANS-based CFD using modern advanced turbulence models, scale-resolving hybrid RANS/LES methods and LES methods. The obtained results are used for the investigation of open questions related to the mechanisms of the three-dimensional buffet phenomenon on swept wings, or to the interaction of a turbulent wake with the horizontal tailplane. In addition, obtained aerodynamic data are used to advance the development of computationally efficient, industrially applicable reduced order models.  The University of Stuttgart, the Technical Universities of Braunschweig and Munich, RWTH Aachen University and DLR are involved in this research initiative.

The scientific effort is funded by Deutsche Forschungsgemeinschaft (DFG) as research group FOR 2895, which is divided into seven subprojects (TP1-TP7). The wind tunnel experiments in the ETW are financed by the Helmholtz-Gemeinschaft (HGF) with a contribution from German Aerospace Center (DLR). This "ETW measurement project" includes the design and manufacture of additional components for the wind tunnel model. The original model itself is provided by Airbus.