Dependence of the wake on inclination of a stationary cylinder

T. Zhou, Siti Fatin Mohd Razali, Y. Zhou, L. P. Chua, L. Cheng

Research output: Contribution to journalArticle

33 Citations (Scopus)

Abstract

Three-dimensional vorticity in the wake of an inclined stationary circular cylinder was measured simultaneously using a multi-hot wire vorticity probe over a streamwise range of x/d = 10-40. The study aimed to examine the dependence of the wake characteristics on cylinder inclination angle α (=0°-45°). The validity of the independence principle (IP) for vortex shedding was also examined. It was found that the spanwise mean velocity W which represents the three-dimensionality of the wake flow, increases monotonically with α. The root-mean-square (rms) values of the streamwise (u) and spanwise (w) velocities and the three vorticity components decrease significantly with the increase of α, whereas the transverse velocity (v) does not follow the same trend. The vortex shedding frequency decreases with the increase of α. The Strouhal number (StN), obtained by using the velocity component normal to the cylinder axis, remains approximately a constant within the experimental uncertainty (±8%) when α is smaller than about 40°. The autocorrelation coefficients ρu and ρv of the u and v velocity signals show apparent periodicity for all inclination angles. With increasing α, ρu and ρv decrease and approach zero quickly. In contrast, the autocorrelation coefficient ρw of w increases with α in the near wake, implying an enhanced three-dimensionality of the wake.

Original languageEnglish
Pages (from-to)1125-1138
Number of pages14
JournalExperiments in Fluids
Volume46
Issue number6
DOIs
Publication statusPublished - Jun 2009
Externally publishedYes

Fingerprint

wakes
inclination
Vorticity
vorticity
vortex shedding
Vortex shedding
Autocorrelation
autocorrelation
near wakes
mean square values
Strouhal number
circular cylinders
coefficients
Circular cylinders
periodic variations
wire
Wire
trends
probes

ASJC Scopus subject areas

  • Physics and Astronomy(all)
  • Fluid Flow and Transfer Processes
  • Computational Mechanics
  • Mechanics of Materials

Cite this

Dependence of the wake on inclination of a stationary cylinder. / Zhou, T.; Mohd Razali, Siti Fatin; Zhou, Y.; Chua, L. P.; Cheng, L.

In: Experiments in Fluids, Vol. 46, No. 6, 06.2009, p. 1125-1138.

Research output: Contribution to journalArticle

Zhou, T. ; Mohd Razali, Siti Fatin ; Zhou, Y. ; Chua, L. P. ; Cheng, L. / Dependence of the wake on inclination of a stationary cylinder. In: Experiments in Fluids. 2009 ; Vol. 46, No. 6. pp. 1125-1138.
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