Large-scale turbulent boundary layer investigation with multiple camera PIV and hybrid evaluation up to single pixel resolution

Abstract

In order to characterize the large-scale coherent flow motion in turbulent boundary layers and its sensitivity to pressure gradients, the flow along a 13 m long flat plate with a s-shaped deflection was examined. A multiple camera PIV system was installed to resolve simultaneously the boundary layer over more than 3 m in stream-wise direction. Furthermore, stereoscopic PIV and long-range μPIV measurements were performed to estimate various components of the Reynolds stress tensor and to determine the wall-shear stress directly. The wall-shear stress is very important for the normalisation of the data, especially for the non-flat plate flow regimes. As the data will be used in the future to validate numerical flow simulations, this paper focuses on the experimental details and the methodology to estimate the main flow quantities.