Shear Layer and Shedding Modes Excitations of a Backward-Facing Step Flow by Surface Plasma Discharge

  • Nicolas BenardEmail author
  • P. Sujar-Garrido
  • Jean-Paul Bonnet
  • E. Moreau
Part of the Computational Methods in Applied Sciences book series (COMPUTMETHODS, volume 52)


The present experimental study interests in determining the influence of a linear plasma actuator (dielectric barrier discharge) on the development of a separated turbulent shear layer. More specifically, the plasma actuator is used to impose periodic perturbations at the step corner of a backward-facing step. Two different modes of excitation are explored. One concerns the shear layer mode of instability, a mode whose amplification leads to a minimization of the recirculation bubble. The present investigation shows how a dielectric barrier discharge plasma actuator can impose periodic perturbations that excite the shear layer mode and result in a strong regularization of the vortex street. The case of excitation at the shedding mode is also experimentally investigated using a DBD actuator. The measurements show the increase in Reynolds stress caused by this excitation as well as the specific growing mechanism of the shear layer. Indeed, phase-averaged flow measurements highlights the difference in the mechanism of development of the shear layer regarding the type of excitation used, the shear layer mode promoting a growing mechanism by fluid entrainment while the shedding mode enhancing the pairing of successive vortical flow structures.


Flow control Plasma actuator Turbulent shear layer Triple decomposition PIV 



This work was supported by FP7/2010-2013, MARS (grant agreement no. 266326). A part of the equipment has been funded by the French Government program “Investissements d’Avenir” (LABEX INTERACTIFS, reference ANR-11-LABX-0017-01).


  1. 1.
    Chun KB, Sung HJ (1996) Control of turbulent separated flow over a backward-facing step by local forcing. Exp Fluids 21:417–426CrossRefGoogle Scholar
  2. 2.
    Hasan MAZ (1992) The flow over a backward-facing step under controlled perturbation: laminar separation. J Fluid Mech 238:73–96CrossRefGoogle Scholar
  3. 3.
    Winant CD, Browand FK (1974) Vortex pairing: the mechanism of turbulent layer growth at moderate Reynolds number. J Fluid Mech 63:237–255CrossRefGoogle Scholar
  4. 4.
    Yoshioka S, Obi S, Masuda S (2001) Organized vortex motion in periodically perturbed turbulent separated flow over a backward-facing step. Int J Heat Fluid Flow 22:301–307CrossRefGoogle Scholar
  5. 5.
    Hudy LM, Naguib AM, Humphreys WM (2003) Wall-pressure-array measurements beneath a separating/reattaching flow region. Phys Fluids 15CrossRefGoogle Scholar
  6. 6.
    Bhattacharjee S, Scheelke B, Troutt TR (1986) Modification of vortex interactions in a reattaching separated flow. AIAA J 24Google Scholar
  7. 7.
    Gautier N, Aider JL (2015) Frequency-lock reactive control of a separated flow enabled by visual sensors. Exp Fluids 56:1–10CrossRefGoogle Scholar
  8. 8.
    Yoshioka S, Obi S, Masuda S (2001) Turbulence statistics of periodically perturbed separated shear over a backward-facing step. Int J Heat Fluid Flow 22:393–401Google Scholar
  9. 9.
    Pouryoussefi GS, Mirzaei M, Hajipour M (2014) Experimental study of separation bubble control behind a backward-facing step using plasma actuators. Acta Mech 226:1153–1165CrossRefGoogle Scholar
  10. 10.
    d’Adamo J, Sosa R, Artana G (2014) Active control of a backward facing step flow with plasma actuators. J Fluid Eng 136Google Scholar
  11. 11.
    Benard N, Sujar-Garrido P, Braud P, Bonnet JP, Moreau E (2016) Control of the coherent structure dynamics downstream of a backward facing step by DBD plasma actuator. Intern J Heat Fluid Flow 57:1–16CrossRefGoogle Scholar
  12. 12.
    Sujar-Garrido P, Benard N, Moreau E, Bonnet JP (2015) Dielectric barrier discharge plasma actuator to control turbulent flow downstream of a backward-facing step. Exp Fluids 56:70Google Scholar
  13. 13.
    Benard N, Pons-Prats J, Periaux J, Bugeda G, Braud P, Bonnet JP, Moreau E (2016) Turbulent separated shear flow control by surface plasma actuator: experimental optimization by genetic algorithm approach. Exp Fluids 57:1–17CrossRefGoogle Scholar
  14. 14.
    Gautier N, Duriez T, Aider JL, Noack B, Segond M, Abel M (2015) Closed-loop separation control using machine learning. J. Fluid Mech 770:442–457CrossRefGoogle Scholar
  15. 15.
    Ho CM, Huang LS (1982) Subharmonics and vortex merging in mixing layers. J Fluid Mech 119:443–473CrossRefGoogle Scholar
  16. 16.
    Martin RA, Kaul UK (2014) Optimization of perturbation parameters for simulated free shear layer flow. AIAA 2014-2223Google Scholar
  17. 17.
    Cherry NJ, Hillier R, Latour P (1984) Unsteady measurements in a separated and reattaching flow. J Fluid Mech 44Google Scholar
  18. 18.
    Driver DM, Seegmiller HL, Marvin JG (1987) Time-dependent behavior of reattaching shear layer. AIAA J 25Google Scholar
  19. 19.
    Oster D, Wygnanski I (1982) The forced mixing layer between parallel streams. J. Fluid Mechanics 123:91–130CrossRefGoogle Scholar
  20. 20.
    Dandois J, Garnier E, Sagaut P (2007) Numerical simulation of active separation control by a synthetic jet. J Fluid Mech 574:25–58CrossRefGoogle Scholar
  21. 21.
    Mansour NN, Hussain F, Buell C (1988) Subharmonic resonance in a mixing layer. In: Proceedings of the summer program, Center for Turbulent ResearchGoogle Scholar
  22. 22.
    Paschereit CO, Wygnanski I (1991) Instabilities in the axisymmetric jet: subharmonic resonance. In: Unger Y, Branover H (eds) Advances in turbulence studies. Progress in Astronautics and aeronautics.
  23. 23.
    Benard N, Moreau E (2014) Electrical and mechanical characteristics of surface AC dielectric barrier discharge plasma actuators applied to airflow control. Exp Fluids 55:1846CrossRefGoogle Scholar
  24. 24.
    Moreau E., 2007, ‘Airflow control by non-thermal plasma actuators,’ J Phys D: Appl Phys 40CrossRefGoogle Scholar
  25. 25.
    Sujar-Garrido P (2014) Active control of the turbulent flow downstream of a backward facing step with dielectric barrier discharge plasma actuators. Ph.D. thesis, University of PoitiersGoogle Scholar
  26. 26.
    Aono H, Sekimoto S, Sato M, Yakeno A, Nonomura T, Fujii K (2015) Computational and experimental analysis of flow structures induced by a plasma actuator with burst modulations in quiescent air. Mech Eng J 2Google Scholar
  27. 27.
    Benard N, Moreau E (2010) Capabilities of the dielectric barrier discharge plasma actuator for multi-frequency excitations. J Phys D Appl Phys 43:145201CrossRefGoogle Scholar
  28. 28.
    Wang J-J, Choi K-S, Feng L-H, Jukes TN (2013) Recent developments in DBD plasma flow control. Prog Aerosp Sci 62:52–78CrossRefGoogle Scholar
  29. 29.
    Reynolds WC, Hussain AKMF (1972) The mechanics of an organized wave in turbulent shear flow. Part 3. Theoretical models and comparisons with experiments. J Fluid Mech 54:263–288CrossRefGoogle Scholar
  30. 30.
    Jeong J, Hussain F (1995) On the identification of a vortex. J Fluid Mech 285:69–94MathSciNetCrossRefGoogle Scholar
  31. 31.
    Bonnet JP, Delville J, Glauser MN, Antonia RA, Bisset DK, Cole DR, Fiedler HE, Garem JH, Hilberg D, Jeong J, Kevlahan NKR, Ukeiley LS, Vincendeau E (1998) Collaborative testing of eddy structure identification methods in free turbulent shear flows. Exp Fluids 25:197–225CrossRefGoogle Scholar
  32. 32.
    Hudy LM, Naguib AM, Humphreys WM (2007) Stochastic estimation of a separated-flow field using wall-pressure-array measurements. Phys Fluids 19:024103CrossRefGoogle Scholar
  33. 33.
    Troutt TR, Scheelke B, Norman TR (1984) Organized structures in a reattaching separated flow field. J Fluid Mech 143:413–427CrossRefGoogle Scholar
  34. 34.
    Dejoan A, Leschziner MA (2004) Large eddy simulation of periodically perturbed separated flow over a backward-facing step. Int J Heat Fluid Flow 25:581–592CrossRefGoogle Scholar
  35. 35.
    Hu R, Wang L, Fu S (2016) Investigation of the coherent structures in flow behind a backward-facing step. Int J Numer Meth Heat Fluid Flow 26:1050–1068MathSciNetCrossRefGoogle Scholar
  36. 36.
    Raman G, Rice EJ (1989) Subharmonic and fundamental high amplitude excitation of an axisymmetric jet. AIAA paper 1989-0993Google Scholar

Copyright information

© Springer Nature Switzerland AG 2020

Authors and Affiliations

  • Nicolas Benard
    • 1
    Email author
  • P. Sujar-Garrido
    • 2
  • Jean-Paul Bonnet
    • 1
  • E. Moreau
    • 1
  1. 1.Institut PPRIME (CNRS UPR3346, Université de Poitiers, ISAE-ENSMA)PoitiersFrance
  2. 2.KTH, Linné FLOW CentreStockholmSweden

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