# Streamwise evolution of an inclined cylinder wake

Streamwise evolution of an inclined cylinder wake The streamwise evolution of an inclined circular cylinder wake was investigated by measuring all three velocity and vorticity components using an eight-hotwire vorticity probe in a wind tunnel at a Reynolds number Red of 7,200 based on free stream velocity (U ∞) and cylinder diameter (d). The measurements were conducted at four different inclination angles (α), namely 0°, 15°, 30°, and 45° and at three downstream locations, i.e., x/d = 10, 20, and 40 from the cylinder. At x/d = 10, the effects of α on the three coherent vorticity components are negligibly small for α ≤ 15°. When α increases further to 45°, the maximum of coherent spanwise vorticity reduces by about 50%, while that of the streamwise vorticity increases by about 70%. Similar results are found at x/d = 20, indicating the impaired spanwise vortices and the enhancement of the three-dimensionality of the wake with increasing α. The streamwise decay rate of the coherent spanwise vorticity is smaller for a larger α. This is because the streamwise spacing between the spanwise vortices is bigger for a larger α, resulting in a weak interaction between the vortices and hence slower decaying rate in the streamwise direction. For all tested α, the coherent contribution to $$\overline{{v^{2}}}$$ is remarkable at x/d = 10 and 20 and significantly larger than that to $$\overline{{u^{2}}}$$ and $$\overline{{w^{2}}}.$$ This contribution to all three Reynolds normal stresses becomes negligibly small at x/d = 40. The coherent contribution to $$\overline{{u^{2}}}$$ and $$\overline{{v^{2}}}$$ decays slower as moving downstream for a larger α, consistent with the slow decay of the coherent spanwise vorticity for a larger α. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Experiments in Fluids Springer Journals

# Streamwise evolution of an inclined cylinder wake

, Volume 51 (2) – Mar 24, 2011
18 pages

/lp/springer_journal/streamwise-evolution-of-an-inclined-cylinder-wake-XIkkcZWRgs
Publisher
Springer-Verlag
Subject
Engineering; Engineering Fluid Dynamics; Engineering Thermodynamics, Heat and Mass Transfer; Fluid- and Aerodynamics
ISSN
0723-4864
eISSN
1432-1114
D.O.I.
10.1007/s00348-011-1068-4
Publisher site
See Article on Publisher Site

### Abstract

The streamwise evolution of an inclined circular cylinder wake was investigated by measuring all three velocity and vorticity components using an eight-hotwire vorticity probe in a wind tunnel at a Reynolds number Red of 7,200 based on free stream velocity (U ∞) and cylinder diameter (d). The measurements were conducted at four different inclination angles (α), namely 0°, 15°, 30°, and 45° and at three downstream locations, i.e., x/d = 10, 20, and 40 from the cylinder. At x/d = 10, the effects of α on the three coherent vorticity components are negligibly small for α ≤ 15°. When α increases further to 45°, the maximum of coherent spanwise vorticity reduces by about 50%, while that of the streamwise vorticity increases by about 70%. Similar results are found at x/d = 20, indicating the impaired spanwise vortices and the enhancement of the three-dimensionality of the wake with increasing α. The streamwise decay rate of the coherent spanwise vorticity is smaller for a larger α. This is because the streamwise spacing between the spanwise vortices is bigger for a larger α, resulting in a weak interaction between the vortices and hence slower decaying rate in the streamwise direction. For all tested α, the coherent contribution to $$\overline{{v^{2}}}$$ is remarkable at x/d = 10 and 20 and significantly larger than that to $$\overline{{u^{2}}}$$ and $$\overline{{w^{2}}}.$$ This contribution to all three Reynolds normal stresses becomes negligibly small at x/d = 40. The coherent contribution to $$\overline{{u^{2}}}$$ and $$\overline{{v^{2}}}$$ decays slower as moving downstream for a larger α, consistent with the slow decay of the coherent spanwise vorticity for a larger α.

### Journal

Experiments in FluidsSpringer Journals

Published: Mar 24, 2011

## You’re reading a free preview. Subscribe to read the entire article.

### DeepDyve is your personal research library

It’s your single place to instantly
that matters to you.

over 18 million articles from more than
15,000 peer-reviewed journals.

All for just $49/month ### Explore the DeepDyve Library ### Search Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly ### Organize Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place. ### Access Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals. ### Your journals are on DeepDyve Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more. All the latest content is available, no embargo periods. DeepDyve ### Freelancer DeepDyve ### Pro Price FREE$49/month
\$360/year

Save searches from
PubMed

Create lists to

Export lists, citations