The instantaneous structure of secondary flows in turbulent boundary layers

  title={The instantaneous structure of secondary flows in turbulent boundary layers},
  author={Christina Vanderwel and Alexander Stroh and Jochen Kriegseis and Bettina Frohnapfel and Bharathram Ganapathisubramani},
  journal={Journal of Fluid Mechanics},
  pages={845 - 870}
Secondary flows can develop in turbulent boundary layers that grow over surfaces with spanwise inhomogeneities. In this article, we demonstrate the formation of secondary flows in both experimental and numerical tests and dissect the instantaneous structure and topology of these secondary motions. We show that the formation of secondary flows is not very sensitive to the Reynolds number range investigated, and direct numerical simulations and experiments produce similar results in the mean flow… 

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