A phenomenological model to describe turbulent friction in permeable-wall flows
نویسندگان
چکیده
[1] Describing the canonical properties of turbulent flows over rough-permeable walls such as gravel beds, vegetatedor snow-covered surfaces have, to date, resisted complete theoretical treatment. The major complication in describing such geophysical flows is that the friction factor Reynolds number relationships significantly deviate from their conventional Nikuradse curves or Moody diagrams derived over impermeable rough boundaries. A novel phenomenological model that describes such anomalous behavior is proposed. It expands the approach in Gioia and Chakraborty (2006) developed for rough-impermeable pipes to include finite velocity effects within the porous wall and canonical length scales governing the momentum exchanges between interstitial and superficial flows. Citation: Manes, C., L. Ridolfi, and G. Katul (2012), A phenomenological model to describe turbulent friction in permeable-wall flows, Geophys. Res. Lett., 39, L14403, doi:10.1029/2012GL052369.
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