Skip to main content
Log in

On the vortex dynamics in the wake of a finite surface-mounted square cylinder

  • Research Article
  • Published:
Experiments in Fluids Aims and scope Submit manuscript

Abstract

The shedding process in the near wake of a surface-mounted, square cross-section cylinder of height-to-width aspect ratio 4 at a Reynolds number of 12,000 based on free-stream velocity and the obstacle width was investigated. The boundary layer thickness was 0.18 obstacle heights based on 99% free-stream velocity. The study is performed using planar high frame-rate particle image velocimetry synchronized with pressure measurements and hot-wire anemometry. Spatial cross-correlation, instantaneous phase relationships, and phase-averaged velocity data are reported. Two dominant vortex-shedding regimes are observed. During intervals of high-amplitude pressure fluctuations on the obstacle side faces, alternate formation and shedding of vortices is observed (regime A) similar to the von Kármán process. Regime B is characterized by two co-existing vortices in the obstacle lee throughout the shedding cycle and is observed within low-amplitude pressure fluctuation intervals. Despite the coexisting vortices in the base region, opposite sign vorticity is still shed out-of-phase downstream of this vortex pair giving rise to a staggered arrangement of counter-rotating vortices downstream. While the probability of occurrence of Regime B increases toward the free end, the amplitude modulation remains coherent along the obstacle height. Conditionally phase-averaged reconstructions of the flow field are consistent with the spatial distribution of the phase relationships and their probability density function. Earlier observations are reconciled showing that the symmetric shedding of vortices is a rare occurrence.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11
Fig. 12
Fig. 13
Fig. 14
Fig. 15
Fig. 16
Fig. 17
Fig. 18
Fig. 19
Fig. 20
Fig. 21
Fig. 22
Fig. 23
Fig. 24
Fig. 25

Similar content being viewed by others

References

  • Ayoub A, Keramcheti K (1982) An experiment on the flow past a finite circular cylinder at high subcritical and supercritical Reynolds numbers. J Fluid Mech 118:1–26

    Article  Google Scholar 

  • Bailey SCC, Martinuzzi RJ, Kopp GA (2002) The effects of wall proximity on vortex shedding from a square cylinder. Phys Fluids 14(12):4160–4177

    Article  Google Scholar 

  • Bearman PW, Obasaju ED (1982) An experimental study of pressure fluctuations on fixed and oscillating square-section cylinders. J Fluid Mech 119:297–321

    Article  Google Scholar 

  • Bearman PW, Trueman DM (1972) An investigation of the flow around rectangular cylinders. Aerodyn Q 23:229–237

    Google Scholar 

  • Bourgeois JA, Sattari P, Martinuzzi RJ (2011) Alternating half-loop shedding in the turbulent wake of a finite surface-mounted square cylinder with a thin boundary layer. Phys Fluids 23(9). doi:10.1063/1.3623463

  • Cantwell B, Coles D (1983) An experimental study of entrainment and transport in the turbulent wake of a circular cylinder. J Fluid Mech 136:321–374

    Article  Google Scholar 

  • Castro IP, Rogers P (2002) Vortex shedding from tapered plates. Exp Fluids 33:66–74

    Google Scholar 

  • Castro IP, Watson L (2004) Vortex shedding from tapered, triangular plates: taper and aspect ratio effects. Exp Fluids 37:159–167

    Article  Google Scholar 

  • Chong MS, Perry AE, Cantwell BJ (1990) A general classification of three-dimensional flow fields. Phys Fluids A 2:765–777

    Article  MathSciNet  Google Scholar 

  • Coleman HW, Steele WG (1999) Experimentation and uncertainty analysis for engineers, 2nd edn. Wiley, New York

    Google Scholar 

  • Eisenlohr H, Eckelmann H (1989) Vortex splitting and its consequences in the vortex street wake of cylinders at low Reynolds number. Phys Fluids A 1(2):189–192

    Article  Google Scholar 

  • Ezepessy S, Bearman PW (1992) Aspect ratio and end plate effects on vortex shedding from a circular cylinder. J Fluid Mech 234:191–217

    Article  Google Scholar 

  • Gerich D, Eckelmann H (1982) Influence of end plates and free ends on the shedding frequency of circular cylinders. J Fluid Mech 122:109–121

    Article  Google Scholar 

  • Griffin OM (1995) A note on bluff body vortex formation. J Fluid Mech 284:217–224

    Article  Google Scholar 

  • Igarashi T (1985) Heat Transfer from a square prism to an air stream. Int J Heat Mass Transf 28:175–181

    Article  Google Scholar 

  • Jeong J, Hussain F (1995) On the identification of a vortex. J Fluid Mech 285:69–94

    Article  MathSciNet  MATH  Google Scholar 

  • Kiya M, Ishikawa H, Sakamoto H (2001) New-wake instabilities and vortex structures of three-dimensional bluff bodies: a review. J Wind Eng Indus Aerodyn 89:1219–1232

    Article  Google Scholar 

  • Lyn DA, Einav S, Rodi W, Park J-H (1995) A laser-doppler velocimetry study of ensemble-averaged characteristics of the turbulent near wake of a square cylinder. J Fluid Mech 304:285–319

    Article  Google Scholar 

  • Martinuzzi RJ (2008) Dual vortex structure shedding from low aspect ratio, surface-mounted pyramids. J Turbulence 9:1–16

    Article  Google Scholar 

  • Martinuzzi RJ, AbuOmar M (2003) Study of the flow around surface-mounted pyramids. Exp Fluids 34:379–389

    Article  Google Scholar 

  • Miau JJ, Wu SJ, Hu CC, Chou JH (2004) Low-frequency modulations associated with vortex shedding due to flow over a bluff body. AIAA J 42:1388–1397

    Article  Google Scholar 

  • Najjar FM, Balachander S (1998) Low-frequency unsteadiness in the wake of a normal flat plate. J Fluid Mech 370:101–147

    Article  MATH  Google Scholar 

  • Noack B, Afanasiev K, Morzyński M, Tadmor G, Thiele F (2003) A hierarchy of low-dimensional models for the transient and post-transient cylinder wake. J Fluid Mech 497:335–363

    Article  MathSciNet  MATH  Google Scholar 

  • Okamoto S, Sunabashiri Y (1992) Vortex shedding from a circular cylinder of finite length placed on a ground plane. J Fluid Eng 114:512–521

    Article  Google Scholar 

  • Park C-W, Lee S-J (2002) Flow structure around a finite circular cylinder embedded in various atmospheric boundary layers. Fluid Dyn Res 30:197–215

    Article  Google Scholar 

  • Park C-W, Lee S-J (2003) Flow structure around two finite circular cylinders located in an atmospheric boundary layer: side-by-side arrangement. J Fluids Struct 17:1043–1058

    Article  Google Scholar 

  • Roshko A (1954) On the drag and shedding frequency of two-dimensional bluff bodies. NACA Technical Note 3169

  • Sakamoto H, Arie M (1983) Vortex shedding from a rectangular prism and a circular cylinder placed vertically in a turbulent boundary layer. J Fluid Mech 126:147–165

    Article  Google Scholar 

  • Sakamoto H, Oiwake S (1984) Fluctuating forces on a rectangular prism and a circular cylinder places vertically in a turbulent boundary layer. J Fluid Eng 106:160–166

    Article  Google Scholar 

  • Sumner D, Heseltine JL (2008) Tip vortex structure for a circular cylinder with a free end. J Wind Eng Indus Aerodyn 96:1185–1196

    Article  Google Scholar 

  • Tritton DT (1959) Experiments on flow past circular cylinder at low Reynolds number. J Fluid Mech 6:547–567

    Article  MATH  Google Scholar 

  • Vincent JH (1977) Model experiments on the nature of air pollution transport near buildings. Atmos Boundary Layers 11:765–774

    Google Scholar 

  • Vosper SB, Castro IP, Snyder WH, Mobbs SD (1999) Experimental studies of strongly stratified flow past three-dimensional orography. J Fluid Mech 390:123–249

    Article  Google Scholar 

  • Wang HF, Zhou Y (2009) The Finite-length square cylinder near wake. J Fluid Mech 638:453–490

    Article  MATH  Google Scholar 

  • Wang HF, Zhou Y, Chan CK, Lam KS (2006) Effect of initial conditions on interaction between a boundary layer and a wall-mounted finite-length-cylinder wake. Phys Fluids 18:065106-1

    Google Scholar 

  • Wang H, Zhou Y, Chan C, Zhou T (2009) Momentum and heat transport in a finite length cylinder wake. Exp Fluids 46:1173–1185

    Article  Google Scholar 

  • Westerweel J (2000) Theoretical analysis of the measurement precision in particle image velocimetry. Exp Fluids 29:S3–S12

    Article  Google Scholar 

  • Williamson CHK (1992) The natural and forced formation of spot-like ‘vortex dislocations’ in the transition of a wake. J Fluid Mech 243:393–441

    Article  Google Scholar 

  • Williamson CHK (1996) Vortex dynamics in the cylinder wake. Annu Rev Fluid Mech 28:477–539

    Article  Google Scholar 

  • Wu SJ, Miau JJ, Hu CC, Chou JH (2005) On low-frequency modulations and three-dimensionality in vortex shedding behind a normal plate. J Fluid Mech 526:117–146

    Article  MATH  Google Scholar 

  • Zhou Y, Antonia RA (1992) Convection velocity measurements in a cylinder wake. Exp Fluids 13:63–70

    Article  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to R. J. Martinuzzi.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Sattari, P., Bourgeois, J.A. & Martinuzzi, R.J. On the vortex dynamics in the wake of a finite surface-mounted square cylinder. Exp Fluids 52, 1149–1167 (2012). https://doi.org/10.1007/s00348-011-1244-6

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00348-011-1244-6

Keywords

Navigation