Investigation of unsteady secondary flows and large-scale turbulence in heterogeneous turbulent boundary layers

  title={Investigation of unsteady secondary flows and large-scale turbulence in heterogeneous turbulent boundary layers},
  author={Dea D. Wangsawijaya and Nicholas Hutchins},
  journal={Journal of Fluid Mechanics},
Abstract Following the findings by Wangsawijaya et al. (J. Fluid Mech., vol. 894, 2020, A7), we re-examine the turbulent boundary layers developing over surfaces with spanwise heterogeneous roughness of various roughness half-wavelengths $0.32 \leq S/\bar {\delta } \leq 3.63$, where $S$ is the width of the roughness strips and $\bar {\delta }$ is the spanwise-averaged boundary-layer thickness. The heterogeneous cases induce counter-rotating secondary flows, and these are compared with the large… 


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  • N. Hutchins, I. Marusic
  • Mathematics, Medicine
    Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences
  • 2007
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