Journal of Visualization

, Volume 12, Issue 4, pp 307–321 | Cite as

Interacting wakes of two normal flat plates an investigation based on phase averaging of LDA signals

  • Auteri F. 
  • Belan M. 
  • Cassinelli C. 
  • Gibertini G. 
Regular Paper


The flow around two bluff bodies in tandem is an interesting phenomenon whose nature strongly depends on the distance between the bodies. In this work oil smoke visualizations of the flow around two normal flat plates in tandem configuration are compared with phase averaged Laser Doppler Anemometry measurements of the flow field for a full period. Phase averaging is exploited to resolve the mean time evolution of the flow and the signal from a single constant temperature hot wire probe is employed as phasing reference. The flow-field information obtained from visualizations agrees well with quantitative indications provided by measures, and the comparison allows to precisely understand what information can be extracted from simple visualizations. As a result, new insight in flow mechanism is obtained from the analysis of the flow data showing that, for the analyzed plate distance, the gap between the two plates behaves substantially as a cavity while the vortex formation process takes place in the wake region behind the aft plate.


Flat Plate Bluff bodies Wake Interference Laser Doppler Anemometry Phase averaging 


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  1. Kim, K. C., Lee, M. B., Yoon, S. Y., Boo, J. S. and Chun, H. H., Phase averaged velocity field in the near wake of a square cylinder obtained by a PIV method, Journal of Visualization, 5 (2002), 29–36.CrossRefGoogle Scholar
  2. Zdravkovich, M.M., Review of flow interference between two circular cylinders in various arrangements, J Fluids Eng, 99 (1977), 618–633.Google Scholar
  3. Igarashi, T., Characteristics of the flow around two circular cylinders arranged in tandem, 1st. report Bull JSME, 24 (1981), 323–331.Google Scholar
  4. Igarashi, T., Characteristics of the flow around two circular cylinders arranged in tandem, 2nd. report Bull JSME, 27 (1984), 2380–2387.Google Scholar
  5. Lin, J.C., Yang, Y. and Rockwell, D., Flow past two cylinders in tandem: instantaneous and averaged flow structure, J Fluids Struct., 16 (2002), 1059–1071.CrossRefGoogle Scholar
  6. Jester, W. and Kallinderis, Y., Numerical study of incompressible flow about fixed cylinder pairs, J Fluids Struct., 17 (2003), 561–577.CrossRefGoogle Scholar
  7. Xu, G. and Zhou, Y., Strouhal numbers in the wake of the inline cylinders, Experimental in Fluids, 37 (2004), 248–256.Google Scholar
  8. Takeuchi, T. and Matsumoto, M., Aerodynamic response characteristics of rectangular cylinders in tandem arrangement, J Wind Eng Ind. Aerodyn., 41–44 (1992), 582–600.Google Scholar
  9. Luo, S.C., Li, L.L. and Shah, D.A., Aerodynamic stability of the downstream of the two tandem square-section cylinders, J Wind Eng Ind. Aerodyn., 79 (1999), 79–103.CrossRefGoogle Scholar
  10. Havel, B., Hangan, H. and Martinuzzi, R., Buffeting for 2D and 3D sharp-edged bluff bodies, J Wind Eng Ind. Aerodyn., 89 (2001), 1369–1381.CrossRefGoogle Scholar
  11. Xu, S.J., Zhou, Y. and Mi, J., Flow visualization behind a streamwise oscillating cylinder and a stationary cylinder in tandem arrangement Journal of Visualization, 7 (2004), 201–208.CrossRefGoogle Scholar
  12. Liu, C.H., and Chen, J.M., Observation of hysteresis in flow around two square cylinders in a tandem arrangement, J Wind Eng Ind. Aerodyn., 90 (2002), 1019–1050.CrossRefGoogle Scholar
  13. Auteri, F., Belan, M., Gibertini, G. and Grassi, D., Normal flat plates in tandem: an experimental investigation, J Wind Eng Ind. Aerodyn., 96 (2008), 872–879.CrossRefGoogle Scholar
  14. Ota, T., Okamoto, Y. and Yoshikawa, H., A correction formula for wall effects on unsteady forces of two-dimensional bluff bodies, J Fluids Eng, 116 (1994), 414–418.CrossRefGoogle Scholar
  15. Auteri, F., Belan, M., Cassinelli, C. and Gibertini, G., Two interacting wakes of two flat plates, BBAA VI International Colloquium, 2008.Google Scholar
  16. Domnick, J. and Martinuzzi, R., A cheap and effective alternative for particle seeding fluid in LDA-applications, Experiments in Fluids, 16 (1994), 292–295.CrossRefGoogle Scholar
  17. Cantwell B. and Coles D., An experimental study of entrainment and transport in the turbulent near wake of a circular cylinder, J Fluid Mech, 136 (1983), 321–374.CrossRefGoogle Scholar
  18. Perry A.E. and Steiner T.R., Large scale vortex structures in turbulent wakes behind bluff bodies. Part 1. Vortex formation processes, J Fluid Mech, 174 (1987), 233–270.CrossRefGoogle Scholar
  19. Kiya M. and Matsumura M., Incoherent turbulence structure in the near wake of a normal plate, J Fluid Mech, 190 (1988), 343–356.CrossRefGoogle Scholar
  20. Lyn, D.A., Einav, S., Rodi, W. and Park, J.-H., A laser-Doppler velocimetry study of ensemble-averaged characteristics of the turbulent near wake of a square cylinder, J of Fluid Mechanics, 304 (1995), 285–319.CrossRefGoogle Scholar
  21. Göttlich, E., Neumayer, F., Woisetschläger, J., Sanz, W. and Heitmeir, F., Investigation of Stator-Rotor Interaction in a Transonic Turbine Stage Using Laser Doppler Velocimetry and Pneumatic Probes, J of Turbomachinery, 126 (2004), 297–305.CrossRefGoogle Scholar
  22. Seelhorst, U., Beensten, B.M.J. and Butefish, K.A., Flow field investigation of a rotating helicopter rotor blade by three-component laser Doppler velocimetry, AGARD CP 55 (1994).Google Scholar
  23. Wernert, P. and Favier, D., Considerations about the phase averaging method with application to ELDV and PIV measurements over pitching airfoils, Experiments in Fluids, 27 (1999), 473–483.CrossRefGoogle Scholar
  24. Sonnenberger, R., Graichen, K. and Erk, P., Fourier averaging: a phase averaging method for periodic flow, Experiments in Fluids, 28 (2000), 217–224.CrossRefGoogle Scholar

Copyright information

© The Visualization Society of Japan 2009

Authors and Affiliations

  • Auteri F. 
    • 1
  • Belan M. 
    • 1
  • Cassinelli C. 
    • 1
  • Gibertini G. 
    • 1
  1. 1.Dipartimento di Ingegneria AerospazialePolitecnico di MilanoMilanoItaly

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