High resolution velocity profile measurements in turbulent boundary layers

In this article, the results of a turbulent boundary layer investigation performed in a large wind tunnel are discussed to assess the measurement uncertainty in estimating relevant quantities such as the boundary layer thickness, the friction velocity and the wall-shear stress. The recordings were evaluated using PIV ensemble correlation image analysis approaches with single pixel resolution but also PTV evaluation concepts with even better resolution and lower uncertainty were applied. The analysis shows that all relevant values can be estimated with high precision but measurement errors caused by the finite thickness of the light-sheet must be considered with the approaches outlined in this article.