Wavelet analysis of the turbulent wake generated by an inclined circular cylinder

Siti Fatin Mohd Razali, T. Zhou, A. Rinoshika, L. Cheng

Research output: Contribution to journalArticle

11 Citations (Scopus)

Abstract

Three-dimensional velocity and vorticity characteristics in the near wake of a stationary circular cylinder at an inclination angle α in the range of 0°-45° are analysed using the wavelet multiresolution technique, where α = 0° represents the case of the cylinder in a cross-flow. This study aims to examine the dependence of the velocity and vorticity characteristics at different wavelet levels on α as compared with that obtained at α = 0°. The validity of the independence principle (IP) for vortex shedding was also examined. It was found that the IP is only applicable for α < 45°. The energy spectra for the intermediate and large-scale structures decrease in terms of their maximum energy and disperse extensively over an enlarged frequency band with the increase of α. At α =45°,thelarge-scale vortex dislocations may occur be cause of the increase of the three-dimensionality in the wake region. The consequences of vortex dislocations in the wake region can also be seen from the results of the velocity and vorticity variances and velocity autocorrelation coefficients at wavelet level 7. Although the large-scale structures are the dominant contributors to the Reynolds stresses at all inclination angles and followed by the intermediate-scale structures, the wake vorticity is mostly dominated by the smalland intermediate-scale structures and has the smallest values at large-scale structures.

Original languageEnglish
Pages (from-to)1-14
Number of pages14
JournalJournal of Turbulence
Volume11
DOIs
Publication statusPublished - 2010
Externally publishedYes

Fingerprint

turbulent wakes
Wavelet analysis
circular cylinders
Circular cylinders
Vorticity
wavelet analysis
vorticity
wakes
Vortex flow
inclination
Vortex shedding
Autocorrelation
vortices
Frequency bands
near wakes
cross flow
vortex shedding
Reynolds stress
autocorrelation
energy spectra

Keywords

  • Inclined cylinder wake
  • Turbulent structures
  • Turbulent wakes
  • Vortex shedding

ASJC Scopus subject areas

  • Mechanics of Materials
  • Computational Mechanics
  • Physics and Astronomy(all)
  • Condensed Matter Physics

Cite this

Wavelet analysis of the turbulent wake generated by an inclined circular cylinder. / Mohd Razali, Siti Fatin; Zhou, T.; Rinoshika, A.; Cheng, L.

In: Journal of Turbulence, Vol. 11, 2010, p. 1-14.

Research output: Contribution to journalArticle

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