Spatially averaged flows over mobile rough beds: definitions, averaging theorems, and conservation equations

Vladimir Nikora*, Francesco Ballio, Stephen Coleman, Dubravka Pokrajac

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

38 Citations (Scopus)
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This paper reports the double-averaged (in space and in time) hydrodynamic equations for mobile-boundary conditions that are derived based on the refined double-averaging theorems, modified Reynolds decomposition, and improved definitions of the spatial and time bed porosities. The obtained double-averaged conservation equations provide a mathematical framework for studying mobile-boundary flows such as gravel bed rivers during flood events or flows over vegetated beds. These equations will help in designing measurement campaigns for obtaining mobile bed data and their interpretation and parameterization, eventually leading to improved and more robust predictive models. (C) 2013 American Society of Civil Engineers.

Original languageEnglish
Pages (from-to)803-811
Number of pages9
JournalJournal of Hydraulic Engineering
Issue number8
Publication statusPublished - 1 Aug 2013


  • open channel flow
  • turbulence
  • sediment transport
  • vegetation
  • open-channel flow
  • vegetated flows
  • turbulent kinetic-energy
  • overland flows
  • vegetation
  • canopies
  • systems
  • model

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