Transition in Rough Channels

  • Paolo Orlandi
Conference paper
Part of the IUTAM Bookseries book series (IUTAMBOOK, volume 22)


In this paper DNS of turbulent rough channels has been used to show that \(\tilde{u}_{2} \) | w (the normal Reynolds stress at the top of the roughness elements) is a useful quantity for detection of the transition from laminar to turbulent flow. In addition, \(\tilde{u}_{2} \) | w is linked to the roughness function, allowing for the derivation of a simple expression for the velocity profile in the log region. From this equation a new Moody diagram has been created, which may be used for the prediction of rough flows at high Reynolds numbers.


Reynolds Number Direct Numerical Simulation Roughness Element Smooth Wall Turbulent Regime 
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Copyright information

© Springer Science+Business Media B.V. 2010

Authors and Affiliations

  1. 1.Dipartimento di Meccanica e AeronauticaUniversita’ di Roma “La Sapienza”RomaItaly

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