Turbulent boundary layer investigation with multiple camera PIV

Abstract

A multi-camera experimental setup was used for resolving the turbulent boundary layer on a large model installed in the atmospheric wind tunnel at the Universität der Bundeswehr München. The flow was resolved instantaneously over 3m in stream-wise extent. The consecutive application of optical measurements with higher resolution led to the exposition of the scale multitude appearing in turbulent boundary layers at higher Reynolds numbers. The vast data base is used for flow-mechanical analysis of the governing physical laws and mechanistic modeling based on coherent structures. First results for the mean-flow velocity profiles and for the integral boundary layer quantities are presented and the different particle image velocimetry (PIV) approaches, i.e., mono-PIV, stereo PIV and longe-range PIV are compared, including their predictions for the logarithmic law-of-the-wall and its coefficients. Additionally, the main structure in terms of the fluctuating stream-wise velocity is analyzed.