Advertisement

Experiments in Fluids

, Volume 8, Issue 1–2, pp 1–12 | Cite as

The turbulent flow field around a circular cylinder

  • B. Dargahi
Originals

Abstract

The flow field around a circular cylinder mounted vertically on a flat bottom has been investigated experimentally. This type of flow occurs in several technical applications, e.g. local scouring around bridge piers. Hydrogen bubble flow visualization was carried out for Reynolds numbers ranging from 6,600 to 65,000. The main flow characteristic upstream of the cylinder is a system of horse-shoe vortices which are shed quasi-periodically. The number of vortices depends on Reynolds number. The vortex system was found to be independent of the vortices that are shed in the wake of the cylinder. The topology of the separated flow contains several separation and attachment lines which are Reynolds number dependent. In the wake region different flow patterns exist for each constant Reynolds number.

Keywords

Vortex Reynolds Number Flow Field Fluid Dynamics Pier 
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.

List of symbols

B

width of flume

b0

wake width

Cd

drag coefficient

Cf

coefficient of skin friction

Cp

pressure coefficient

D

cylinder diameter

Ks

bed roughness

LE

integral length scale

Re

Reynolds number based on Ym

Re (D)

Reynolds number based on D

Re(l)

Reynolds number based on length

U

free stream velocity

Um

mean flow velocity

Us, max

maximum velocity deficiency

u

streamwise velocity

u*

shear velocity

X, Y, Z

cartesian co-ordinate system measured from the cylinder centre

X, Y, Z

longitudinal, vertical and lateral directions

Ym

mean flow depth

δ

boundary layer thickness

Γ

circulation

δd

displacement thickness

θ

momentum thickness

λf

dissipation length scale

ν

kinematic viscosity

Ω

vorticity

τ

shear stress

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Belik, L. 1973: The secondary flow about circular cylinder mounted normal to a flat wall. Aeronaut. Q. 24, 47–54Google Scholar
  2. Clauser, F. H. 1954: Turbulent boundary layers in adverse pressure gradient. J. Aeronaut. Sci. 21, 91–108Google Scholar
  3. Dallmann, U. 1983: Topological structure of three-dimensional vortex flow separation. AIAA 16th fluid plasma dyn. conf. Danvers/MA: American Institute of Aeronautics and AstronauticsGoogle Scholar
  4. Dargahi, B. 1983: Local scouring around bridge piers — A review of practice and theory. Hydraulics lab. Bull. No. 114, Stockholm: R. Inst. Tech.Google Scholar
  5. Goldstein, R. J.; Karni, J. 1984: The effect of a wall boundary layer on local mass transfer from a cylinder in crossflow. J. Heat Transfer 106, 260–267Google Scholar
  6. Hinze, J. O. 1975: Turbulence. New York: McGraw-HillGoogle Scholar
  7. Hunt, J. C. R.; Abell, C. J.; Peterka, S. A.; Woo, H. 1978: Studies of the flow around free or surface-mounted obstacles; applying topology to flow visualization. J. Fluid Mech. 86, 179–200Google Scholar
  8. Johannson, A. V.; Alfredsson, P. H. 1986: Structure of turbulent channel flows. In: Encyclopedia of fluid mechanics (ed. Cheremisinoff, N. P.) pp. 825–869. Houston, London, Paris, Tokyo: GulfGoogle Scholar
  9. Johnston, P. J. 1957: Three-dimensional turbulent boundary layer. Gas Turbine Lab. Report No. 39Google Scholar
  10. Lighthill, M. J. 1963: Introduction. Boundary layer theory. In: Laminar boundary layer (ed. Rosenhead, L. R.) pp. 48–88. Oxford University PressGoogle Scholar
  11. Ludwieg, H.; Tillmann, W. 1950: Investigations of the wall shearing stress in turbulent boundary layers. NACA TM 1285Google Scholar
  12. Maskell, E. G. 1955: Flow separation in three-dimensions. Royal Aircraft Establishment, Faranborough, Report No. Aero 2565Google Scholar
  13. Melville, B. W. 1975: Local scour at bridge sites. University of Auckland, Report No. 117Google Scholar
  14. Patel, V. C. 1965: Calibration of the Preston tube and limitations on its use in pressure gradients. J. Fluid Mech. 23, 185–208Google Scholar
  15. Perry, A. E. Fairlie, B. D. 1974: Critical points in flow patterns. Advances in geophysics. 18 B. New York: Academic PressGoogle Scholar
  16. Perry A. E., Steiner, T. R. 1987: Large-scale vortex structures in turbulent wakes behind bluff bodies. Part 1. Vortex formation processes. J. Fluid Mech. 174, 233–270Google Scholar
  17. Preston, J. H. 1954: The determination of turbulent skin friction by means of pilot tubes. J. Roy. Aeronaut. Soc. 58, 109–121Google Scholar
  18. Roper, A. T. 1967: A cylinder in a shear flow. Colorado State UniversityGoogle Scholar
  19. Roshko, A. 1953: On the development of turbulent wakes from vortex streets. NACA TN 2913Google Scholar
  20. Schraub, F. A.; Kline, S. J.; Henry, J.; Runstadler, P. W.; Littel, A. 1965: Use of hydrogen bubbles for quantitative determination of time-dependent velocity fields in low-speed water flows. J. Basic Eng. 87, 429–444Google Scholar
  21. Schwind, R. G. 1962: The three dimensional boundary layer near a strut. Gas Turbine Laboratory, Report No. 67Google Scholar
  22. Smith, D. W.; Walker, J. E. 1958: Skin-friction measurements in incompressible flow. NACA TN 4231Google Scholar
  23. Tobak, M.; Peake, D. J. 1982: Topology of three-dimensional separated flow. Annu. Rev. Fluid Mech. 14, 51–85CrossRefGoogle Scholar
  24. Wei, T.; Smith, C. R. 1986: Secondary vortices in the wake of circular cylinders. J. Fluid Mech. 169, 513–533Google Scholar

Copyright information

© Springer-Verlag 1989

Authors and Affiliations

  • B. Dargahi
    • 1
  1. 1.Hydraulics LaboratoryThe Royal Institute of TechnologyStockholmSweden

Personalised recommendations