Export citation

Export citation

Choose format for download:

Download Citation
  • Access by Xinjiang University

Asymmetric wake of a horizontal cylinder in close proximity to a solid boundary for Reynolds numbers in the subcritical turbulence regime

Pablo Ouro*, Valentine Muhawenimana, and Catherine A. M. E. Wilson

  • Hydro-environmental Research Centre, School of Engineering, Cardiff University, Cardiff CF24 3AA, United Kingdom

  • *ourop@cardiff.ac.uk
  • muhawenimanav@cardiff.ac.uk
  • wilsonca@cardiff.ac.uk

Phys. Rev. Fluids 4, 104604 – Published 15 October, 2019

DOI: https://doi.org/10.1103/PhysRevFluids.4.104604

Abstract

The near-wake dynamics developed behind a horizontal cylinder with wall proximity effects are elucidated from laboratory experiments and large-eddy simulations (LES). Fixed vertical gap to diameter (G/D) ratios of 0.5 and 1.0 were investigated for Reynolds numbers equal to 6 666, 10 000, and 13 333. The LES results agreed well with the experimental measurements for the time-averaged flow quantities and captured the upward flow motion developed over the lower half of the flow depth as a consequence of the near-wall effect. The presence of a narrow gap between the cylinder and the bed, i.e., G/D=0.5, significantly influenced the dynamics of the vortex generation and shedding which, in consequence, led to an increasingly pronounced asymmetric wake distribution with increasing Reynolds number. In the wider gap case of G/D=1.0, the wake remained relatively symmetrical, with reduced impact of ground proximity. Kelvin-Helmholtz instabilities developed in the upper and lower shear layers were shown to be decoupled as their instantaneous laminar-to-turbulent transition occurred at different downstream distances at any given time. Spanwise rollers were shown to form with an undulating pattern and presented irregularly located vortex dislocations. Furthermore, a ground vortex induced during the early stages of the lower roller's generation in the wake lifted off the ground and merged with the von Kármán vortices to form a single vortical structure. For G/D=0.5, a positive upwards force was present, and experimental and LES Strouhal number values ranged between 0.28–0.32, while computed drag coefficient values were lower than those typical for unbounded cylinder flows. As for G/D=1.0, Strouhal numbers decrease to a 0.26–0.30 range while drag coefficient increases, further demonstrating the effects on the cylinder wake structure dynamics due to the proximity to a solid boundary.

Physics Subject Headings (PhySH)

Article Text

References (53)

  1. T. Nishino, G. T. Roberts, and X. Zhang, Vortex shedding from a circular cylinder near a moving ground, Phys. Fluids 19, 025103 (2007).
  2. A. Oner, M. Kirkgoz, and M. Akoz, Interaction of a current with a circular cylinder near a rigid bed, Ocean Eng. 35, 1492 (2008).
  3. S. Sankar and S. Sankar, Vortex dynamics of a cylinder wake in proximity to a wall, J. Fluids Struct. 26, 19 (2010).
  4. M. Unal and D. Rockwell, On vortex shedding from a cylinder: Part 1. The initial instability, J. Fluid Mech. 190, 491 (1988).
  5. C. Chyu, J. Lin, J. Sheridan, and D. Rockwell, Karman vortex formation from a cylinder: Role of phase-locked Kelvin-Helmholtz vortices, Phys. Fluids 7, 2288 (1995).
  6. O. Lehmkuhl, I. Rodriguez, R. Borrell, and A. Oliva, Low-frequency unsteadiness in the vortex formation region of a circular cylinder, Phys. Fluids 25, 085109 (2013).
  7. D. Aljure, O. Lehmkhul, I. Rodriguez, and A. Oliva, Three dimensionality in the wake of the flow around a circular cylinder at Reynolds number 5000, Comput. Fluids 147, 102 (2017).
  8. A. Prasad and C. H. Williamson, The instability of the separated shear layer from a bluff body, Phys. Fluids 8, 1347 (1996).
  9. C. Norberg, An experimental investigation of the flow around a circular cylinder: Influence of aspect ratio, J. Fluid Mech. 258, 287 (1994).
  10. C. Wieselsberger, Neuere feststellungen uber die gesetze des flussigkeits und luftwiderstands, Phys. Z. 22, 321 (1921).
  11. A. Roshko, Experiments on the flow past a circular cylinder at very high Reynolds number, J. Fluid Mech. 10, 345 (1961).
  12. O. Lehmkuhl, I. Rodriguez, R. Borrell, J. Chiva, and A. Oliva, Unsteady forces on a circular cylinder at critical Reynolds numbers, Phys. Fluids 26, 125110 (2014).
  13. C. Williamson, Vortex dynamics in the cylinder wake, Annu. Rev. Fluid. Mech 28, 477 (1996).
  14. D. Sumner, Flow above the free end of a surface-mounted finite-height circular cylinder: A review, J. Fluids Struct. 43, 41 (2013).
  15. P. Bearman and M. Zdravkovich, Flow around a circular cylinder near a plane boundary, J. Fluid Mech. 89, 33 (1978).
  16. S. Price, D. Sumner, J. Smith, K. Leong, and M. Paidussis, Flow visualisation around a circular cylinder near to a plane wall, J. Fluids Struct. 16, 175 (2002).
  17. M. Kirkgoz, A. Oner, and M. Akoz, Numerical modeling of interaction of a current with a circular cylinder near a rigid bed, Adv. Eng. Software 40, 1191 (2009).
  18. B. E. Stewart, M. C. Thompson, T. Leweke, and K. Hourigan, The wake behind a cylinder rolling on a wall at varying rotation rates, J. Fluid Mech. 648, 225 (2010).
  19. A. Rao, M. Thompson, T. Leweke, and K. Hourigan, The flow past a circular cylinder translating at different heights above a wall, J. Fluids Struct. 41, 9 (2013).
  20. A. Roshko, A. Steinolfson, and V. Chattoorgoon, Flow forces on a cylinder near a wall or near another cylinder, in Proceedings of the 2nd US Nation Conference on Wind Engineering Research, Fort Collins, Paper IV-15 (IAWE, Fort Collins, 1975).
  21. J. Choi and S. Lee, Ground effect of flow around an elliptic cylinder in a turbulent boundary layer, J. Fluids Struct. 14, 697 (2000).
  22. M. Zdravkovich, Forces on a circular cylinder near a plane wall, Appl. Ocean Res. 7, 197 (1985).
  23. C. Lei, L. Cheng, and K. Kavanagh, Re-examination of the effect of a plane boundary on force and vortex shedding of a circular cylinder, J. Wind Eng. Industr. Aerodynam. 80, 263 (1999).
  24. F. Angrilli, S. Bergamaschi, and V. Cossalter, Investigation of wall-induced modifications to vortex shedding from a circular cylinder, J. Fluids Eng. 104, 518 (1982).
  25. S. Taniguchi and K. Miyakoshi, Fluctuating fluid forces acting on a circular cylinder and interference with a plane wall, Exp. Fluids 9, 197 (1990).
  26. T. Nishino, G. T. Roberts, and X. Zhang, Unsteady RANS and detached-eddy simulations of flow around a circular cylinder in ground effect, J. Fluids Struct. 24, 18 (2008).
  27. M. Breuer, Large-eddy simulations of the subcritical flow past a circular cylinder: Numerical and modeling aspects, Int. J. Numer. Methods Fluids 28, 1281 (1998).
  28. X. Ma, G.-S. Karamanos, and G. E. Karniadakis, Dynamics and low-dimensionality of a turbulent near wake, J. Fluid Mech. 410, 29 (2000).
  29. D. Goring and V. Nikora, Despiking acoustic doppler velocimeter data, J. Hydraul. Eng 128, 117 (2002).
  30. M. Jesson, M. Sterling, and J. Bridgman, Despiking velocity time series—Optimization through the combination of spike detection and replacement methods, Flow Meas. Instrum. 30, 45 (2013).
  31. L. Cea, J. Puertas, and L. Pena, Velocity measurements on highly turbulent free surface flow using ADV, Exp. Fluids 42, 333 (2007).
  32. T. Stoesser, S. Kim, and P. Diplas, Turbulent flow through idealized emergent vegetation, J. Hydraul. Res. 136, 1003 (2010).
  33. S. Bomminayuni and T. Stoesser, Turbulence statistics in an open-channel flow over a rough bed, J. Hydraul. Eng. 137, 1347 (2011).
  34. D. Kim, T. Stoesser, and J. Kim, The effect of baffle spacing on hydrodynamics and solute transport in serpertine contact tanks, J. Hydraul. Res. 51, 558 (2013).
  35. S. Kara, T. Stoesser, T. W. Sturm, and S. Mulahasan, Flow dynamics through a submerged bridge opening with overtopping, J. Hydraul. Res. 53, 186 (2015).
  36. P. Ouro, C. Wilson, P. Evans, and A. Angeloudis, Large-eddy simulation of shallow turbulent wakes behind a conical island, Phys. Fluids 29, 126601 (2017).
  37. R. McSherry, K. Chua, T. Stoesser, and S. Mulahasan, Free surface flow over square bars at intermediate relative submergence, J. Hydraul. Res. 56, 825 (2018).
  38. F. Nicoud and F. Ducros, Subgrid-scale stress modeling based on the square of the velocity gradient tensor, Flow, Turbul. Combust. 62, 183 (1999).
  39. M. Uhlmann, An immersed boundary method with direct forcing for the simulation of particulate flows, J. Comput. Phys. 209, 448 (2005).
  40. P. Ouro and T. Stoesser, An immersed boundary-based large-eddy simulation approach to predict the performance of vertical axis tidal turbines, Comput. Fluids 152, 74 (2017).
  41. P. Ouro, B. Fraga, U. López-Novoa, and T. Stoesser, Scalability of an Eulerian-Lagrangian large-eddy simulation solver with hybrid MPI/OpenMP parallelisations, Comput. Fluids 179, 123 (2019).
  42. M. Cevheri, R. McSherry, and T. Stoesser, A local mesh refinement approach for large-eddy simulations of turbulent flows, Int. J. Numer. Methods Fluids 82, 261 (2016).
  43. T. Stoesser, Large-eddy simulation in hydraulics: Quo vadis? J. Hydraul. Res. 52, 441 (2014).
  44. R. Broglia, A. Pascarelli, and U. Piomelli, Large-eddy simulations of ducts with a free surface, J. Fluid Mech. 484, 223 (2003).
  45. A. Prasad and C. H. Williamson, The instability of the shear layer separating from a bluff body, J. Fluid Mech. 333, 375 (1997).
  46. M. Rai, A computational investigation of the instability of the detached shear layers in the wake of a circular cylinder, J. Fluid Mech. 659, 375 (2000).
  47. J. Kim and H. Choi, Instability of the shear layer separating from a circular cylinder, in Proceedings of the 3rd AFOSR International Conference on DNS/LES (Greyden Press, Dayton, OH, 2001).
  48. J. Hunt, A. Wray, and P. Moin, Eddies, streams, and convergence zone in turbulent flows, in Proceedings of the Summer Program, Report CTR-S88, NASA Stanford Center for Turbulence Research, 1988, pp. 193–208.
  49. M. Braza, D. Faghani, and H. Persillon, Successive stages and the role of natural vortex dislocations in three-dimensional wake transition, J. Fluid Mech. 439, 1 (2001).
  50. C. Norberg, Pressure forces on a circular cylinder in cross flow, in Proceedings of the IUTAM symposium: Bluff body wakes, dynamics, and instabilities, Goettingen, Germany (1992).
  51. Y.-M. Chiew, Flow around horizontal circular cylinder in shallow flows, J. Waterway Port Coast. Ocean Eng. 117, 25657 (1991).
  52. H. Jiang, L. Cheng, S. Draper, and H. An, Two- and three-dimensional instabilities in the wake of a circular cylidner near a moving wall, J. Fluids Mech. 812, 435 (2017).
  53. A. Grass, P. Raven, R. Stuart, and J. Bray, The influence of boundary layer velocity gradients and bed proximity on vortex shedding from free spanning pipelines, J. Energy Resour. Technol. 106, 70 (1984).

Outline

Information

Sign In to Your Journals Account

Filter

Filter

Article Lookup

Enter a citation