Statistical properties of a coherent structure function for homogeneous isotropic turbulence and turbulent channel flows

Hiromichi Kobayashi, Yasuhiro Tominaga, Taisuke Kubota, Mamoru Tanahashi, Toshio Miyauchi

Research output: Contribution to conferencePaper

Abstract

Statistical properties of a coherent structure function FCS are investigated using DNS data for homogeneous isotropic turbulence and turbulent channel flows. The function FCS is defined as the second invariant Q of a velocity gradient tensor normalized by the magnitude E of the velocity gradient tensor. In homogeneous isotropic turbulence, the probability density function (pdf) of FCS shows good agreement at different Reynolds number. The volume fraction of positive Q and the average of FCS converge to a certain value at high Reynolds number. For the turbulent channel flows, the pdf of FCS at different Reynolds number coincides very well at the distance from the wall in wall units. The profiles of the conditional average of positive and negative Q, the volume fraction, and the near-wall FCS 2 are in good agreement at different Reynolds number and those profiles are given as a function of the distance from the wall in wall units.

Original languageEnglish
Pages335-340
Number of pages6
Publication statusPublished - 2009 Jan 1
Event6th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2009 - Seoul, Korea, Republic of
Duration: 2009 Jun 222009 Jun 24

Other

Other6th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2009
CountryKorea, Republic of
CitySeoul
Period09/6/2209/6/24

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ASJC Scopus subject areas

  • Fluid Flow and Transfer Processes

Cite this

Kobayashi, H., Tominaga, Y., Kubota, T., Tanahashi, M., & Miyauchi, T. (2009). Statistical properties of a coherent structure function for homogeneous isotropic turbulence and turbulent channel flows. 335-340. Paper presented at 6th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2009, Seoul, Korea, Republic of.