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Reactive control of transition induced by free-stream turbulence: an experimental demonstration

Published online by Cambridge University Press:  07 August 2007

FREDRIK LUNDELL*
Affiliation:
Linné Flow Center, KTH Mechanics, Royal Institute of Technology, S-100 44, Stockholm, Sweden

Abstract

The present wind-tunnel experiment demonstrates that a reactive control system is able to decrease the amplitude of random disturbances in a flat-plate boundary layer. The disturbances were induced in a laminar boundary layer by a turbulent free stream. The control system consisted of upstream wall-shear-stress sensors (wall wires) and downstream actuators (suction through holes). An ad hoc threshold-and-delay control algorithm is evaluated and parameter variations were performed in order to find a suitable working point of the control system. Detailed measurements of the flow field show how the control influences the disturbances in the boundary layer, whereas the effect on the mean flow owing to the control is minute. The control system manages to inhibit the growth of the fluctuations of the streamwise velocity component for a considerable distance downstream of the two actuator positions. Further downstream, however, the amplitudes of the fluctuations grow again. The flow rate used to obtain the control effect is one sixth of that necessary if continuous distributed suction is used to reach the same control objective. Finally, correlations and spectra show that the elongation of the structures in the streamwise direction is eliminated in the regions where the control has the largest effect. The spanwise scale of the disturbances is not affected by the control.

Type
Papers
Copyright
Copyright © Cambridge University Press 2007

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References

REFERENCES

Alfredsson, P. H. & Matsubara, M. 2000 Free-stream turbulence, streaky structures and transition in boundary layer flows. AIAA Paper 2000-2534.Google Scholar
Amonlirdviman, K. & Breuer, K. S. 2000 Linear predictive filtering in a numerically simulated turbulent flow. Phys. Fluids 12, 32213228.Google Scholar
Andersson, P., Berggren, M. & Henningson, D. S. 1999 Optimal disturbances and bypass transition in boundary layers. Phys. Fluids 11, 134150.CrossRefGoogle Scholar
Andersson, P., Brandt, L. & Henningson, D. S. 2001 On the breakdown of boundary layer streaks. J. Fluid Mech. 428, 2960.CrossRefGoogle Scholar
Asai, M., Minagawa, M. & Nishioka, M. 2002 The instability and breakdown of a near-wall low-speed streak. J. Fluid Mech. 455, 289314.CrossRefGoogle Scholar
Bakchinov, A. A., Grek, G. R., Klingmann, B. G. B. & Kozlov, V. V. 1995 Transition experiments in a boundary layer with embedded streamwise vortices. Phys. Fluids 7, 820832.Google Scholar
Bakchinov, A. A., Katasonov, M. M., Alfredsson, P. H. & Kozlov, V. V. 1999 Control of boundary layer transition at high FST by localized suction. In IUTAM Symp. on Mechanics of Passive and Active Flow Control (ed. Meier, G. E. A. & Viswanath, P. R.), pp. 159164. Kluwer.Google Scholar
Bewley, T. R., Moin, P. & Temam, R. 2001 DNS-based predictive control of turbulence: an optimal benchmark for feedback algorithms. J. Fluid Mech. 447, 179225.CrossRefGoogle Scholar
Chang, Y., Collis, S. S. & Ramakrishnan, S. 2002 Viscous effect in control of near-wall turbulence. Phys. Fluids 14, 40694080.CrossRefGoogle Scholar
Choi, H., Moin, P. & Kim, J. 1994 Active turbulence control for drag reduction in wall-bounded flows. J. Fluid Mech. 262, 75110.CrossRefGoogle Scholar
Elofsson, P. A., Kawakami, M. & Alfredsson, P. H. 1999 Experiments on the stability of streamwise streaks in plane Poiseuille flow. Phys. Fluids 11, 915930.CrossRefGoogle Scholar
Endo, T., Kasagi, N. & Suzuki, Y. 2000 Feedback control of wall turbulence with wall deformation. Intl J. Heat Fluid Flow 21, 568575.CrossRefGoogle Scholar
Fasel, H. F. 2002 Numerical investigation of the interaction of the Klebanoff-mode with a Tollmien–Schlichting wave. J. Fluid Mech. 450, 133.CrossRefGoogle Scholar
Fransson, J. H. M. & Alfredsson, P. H. 2003 On the disturbance growth in an asymptotic suction boundary layer. J. Fluid Mech. 482, 5190.CrossRefGoogle Scholar
Gad-el-Hak, M. 1989 Flow control. Appl. Mech. Rev. 42, 261292.CrossRefGoogle Scholar
Hamilton, J. M., Kim, J. & Waleffe, F. 1995 Regeneration mechanisms of near-wall turbulence structures. J. Fluid Mech. 287, 317348.CrossRefGoogle Scholar
Hœppner, J., Brandt, L. & Henningson, D. S. 2005 Transient growth on boundary layer streaks. J. Fluid Mech. 537, 91100.CrossRefGoogle Scholar
HÖgberg, M. & Henningson, D. S. 2002 Linear optimal control applied to instabilities in spatially developing boundary layers. J. Fluid Mech. 470, 151179.CrossRefGoogle Scholar
Inasawa, A., Lundell, F., Matsubara, M., Kohama, Y. & Alfredsson, P. H. 2003 Velocity statistics and flow structures observed in bypass transition using stereo PTV. Exps. Fluids 34, 242252.CrossRefGoogle Scholar
Jacobs, R. G. & Durbin, P. A. 2001 Simulations of bypass transition. J. Fluid Mech. 428, 185212.CrossRefGoogle Scholar
Jacobson, S. A. & Reynolds, W. C. 1998 Active control of streamwise vortices and streaks in boundary layers. J. Fluid Mech. 360, 179211.CrossRefGoogle Scholar
Jonáš, P., Mazur, O. & Uruba, V. 2000 On the receptivity of the by-pass transition to the length scale of the outer stream turbulence. Eur. J. Mech. B/Fluids 19, 707722.CrossRefGoogle Scholar
Kendall, J. M. 1998 Experiments on boundary-layer receptivity to freestream turbulence. AIAA Paper 98-0530.Google Scholar
Kerho, M., Heid, J., Kramer, B. & Ng, T. 2000 Active drag reduction using selective low rate suction. AIAA Paper 2000-4018.CrossRefGoogle Scholar
Klingmann, B. G. B., Boiko, A., Westin, K. J. A., Kozlov, V. V. & Alfredsson, P. H. 1993 Experi-ments on the stability of Tollmien–Schlichting waves. Eur. J. Mech. B/Fluids 12, 493514.Google Scholar
Landahl, M. T. 1980 A note on an algebraic instability of inviscid shear flows. J. Fluid Mech. 98, 243251.CrossRefGoogle Scholar
Leib, S. J., Wundrow, D. W. & Goldstein, M. E. 1999 Effect of free-stream turbulence and other vortical disturbances on a laminar boundary layer. J. Fluid Mech. 380, 169203.Google Scholar
Lindgren, B. 2003 Flow facility design and experimental studies of wall-bounded turbulent shear-flows. PhD thesis, Royal Institute of Technology, TRITA-MEK 2002:16.Google Scholar
Luchini, P. 2000 Reynolds number independent instability of the boundary layer over a flat surface: optimal perturbations. J. Fluid Mech. 404, 289309.Google Scholar
Lumley, J.L. 1970 Stochastic TOols in Turbulence. Academic.Google Scholar
Lundell, F. & Alfredsson, P. H. 2003 Experiments on control of streamwise streaks. Eur. J. Mech. B/Fluids 22, 279290.Google Scholar
Lundell, F. & Alfredsson, P. H. 2004 Streamwise scaling of streaks in a boundary layers subjected to free-stream turbulence. Phys. Fluids 14, 18141817.CrossRefGoogle Scholar
Matsubara, M. & Alfredsson, P. H. 2001 Disturbance growth in boundary layers subjected to free stream turbulence. J. Fluid Mech. 430, 149168.CrossRefGoogle Scholar
Rathnasingham, R. & Breuer, K. S. 2003 Active control of turbulent boundary layers. J. Fluid Mech. 495, 209233.Google Scholar
Rebbeck, H. & Choi, K.-S. 2001 Opposition control of near wall turbulence with a piston-type actuator. Phys. Fluids 13, 21422145.CrossRefGoogle Scholar
Reddy, S. C., Schmid, P. J., Baggett, J. S. & Henningson, D. S. Henningson, D. S. 1998 On stabililty of streamwise streaks and transition thresholds in plane channel flows. J. Fluid Mech. 365, 269303.Google Scholar
Ricco, P., Durbin, P. A., Zaki, T. & Wu, X. 2004 Nonlinear evolution of velocity fluctuations in a laminar boundary layer excited by free-stream vortical disturbances. In Proc. Summer Program 2004, pp. 223240. Centre for Turbulence Research.Google Scholar
Sahlin, A., Johansson, A. V. & Alfredsson, P. H. 1988 The possibility of drag reduction by outer layer manipulators in turbulent boundary layers. Phys. Fluids 31, 28142820.CrossRefGoogle Scholar
Waleffe, F. 1995 Hydrodynamic stability and turbulence: beyond transients to a self-sustained process. Stud. Appl. Maths 95, 319343.CrossRefGoogle Scholar
Wundrow, D. W. & Goldstein, M. E. 2001 Effect on a laminar boundary layer of small-amplitude streamwise vorticity in the upstream flow. J. Fluid Mech. 426, 229262.CrossRefGoogle Scholar
Yoshioka, S., Fransson, J. H. M. & Alfredsson, P. H. 2004 Free stream turbulence induced disturbances in boundary layers with wall suction. Phys. Fluids 16, 35303539.Google Scholar
Zaki, T. A. & Durbin, P. A. 2006 Mode interaction and the bypass route to transition. J. Fluid Mech. 531, 85111.CrossRefGoogle Scholar