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Statistics of Single Self-sustaining Attached Eddy in a Turbulent Channel

  • Yongyun HwangEmail author
Conference paper
Part of the ERCOFTAC Series book series (ERCO, volume 23)

Abstract

A Numerical experiment that isolates the motions at a given spanwise length scale is performed based on previous observation on the self-sustaining nature of the eddies in the logarithmic and the wake outer regions [7, 8]. It is shown that the statistics of the isolated self-sustaining motions at a given spanwise length scale are strikingly similar to those of the single attached eddy postulated by Townsend and Perry [1, 2, 5, 6], demonstrating the existence of the attached eddies in turbulent channel flow. Inspecting one-dimensional spectra also leads to build a complete form of the self-similarity of the streamwise length scale and the wall-normal location of all the coherent structures known, including near-wall streaks, quasi-streamwise vortices, very-large-scale motions, and large-scale motions.

Keywords

Reynolds Stress Coherent Structure Streamwise Velocity Spanwise Velocity Logarithmic Region 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer International Publishing Switzerland 2016

Authors and Affiliations

  1. 1.Department of AeronauticsImperial College LondonLondonUK

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