Reynolds number dependency of near-wall statistics of zero-pressure- gradient turbulent boundary layer

Abstract

We report high-resolution LDA and HWA measurements of the streamwise velocity component of a flat-plate turbulent boundary layer (ZPG TBL) over a range of momentum thickness Reynolds number from 1,170 to 3,720. The primary objective of this work is to investigate the near-wall behavior and the scaling of high-order statistics. In particular, we are interested in certain Kármán number dependencies. The obtained data are in excellent agreement with most recent DNS-results, which allows direct comparison of detailed results such as peak value and position of streamwise stress, wall-values of skewness and flatness factors, and turbulence dissipation rate. The experimental data clearly reveal the failure of classical scaling. An alternative mixed scaling based on uτ3/2u e1/2 removes these discrepancies.