Statistical Description of Streamline Segments in a Turbulent Channel Flow with a Wavy Wall

In this study we investigate the statistical properties of so called streamline segments in a turbulent channel flow with one plane and one wavy wall. We give a short overview of the concept of streamline segments and recent results in description and modeling in this field. We find that streamline segments in the vicinity of the wavy wall are significantly smaller on average than in the core region. However, normalizing the length distribution with the mean segment length leads to an almost perfect collapse of the pdfs. This quasi-universal behavior is further highlighted by the comparison to statistics of streamline segments in homogeneous isotropic turbulence. Finally, we investigate the kinematic behavior of streamline segments by means of conditional moments and show differences in scaling behavior compared to the classical structure function analysis.