Turbulent boundary layers feature a characteristic on-and-off behavior which has already been reported in the early days of turbulence research. However, its impact on turbulent statistics has been neglected in the past. Hence, well-established turbulent statistics as velocity or Reynolds stress profiles are based on turbulence as well as on the potential flow. The aim of this research project is to filter out the non-turbulent impact and thus improve the understanding of wall-bounded flows. As this requires the identification of the turbulent/non-turbulent interface with high spatial resolution, the focus of this project is to accurately detect the highly complex interface based on experimental data. Due to the spatial resolution and uncertainty limitations of measurements this analysis is quite challenging as the accurate detection of the interface requires microscopic resolution whereas capturing the spatial and temporal evolution needs macroscopic resolution. For this purpose, measurements are carried out in the atmospheric wind tunnel of the Bundeswehr University. In addition to experiments without pressure gradients, flows with negative and positive pressure gradients are also analyzed.
Person in charge: Dipl.-Ing. Nico Reuther