Hostname: page-component-7bb8b95d7b-l4ctd Total loading time: 0 Render date: 2024-09-17T23:30:31.289Z Has data issue: false hasContentIssue false
  • English
  • Français

Effects of vortex-induced velocity on the development of a synthetic jet issuing into a turbulent boundary layer

Published online by Cambridge University Press:  14 May 2019

Tim Berk Open the ORCID record for Tim Berk [Opens in a new window]  and
Bharathram Ganapathisubramani
Tim Berk
Affiliation:
Aerodynamics and Flight Mechanics Group, University of Southampton, SouthamptonSO17 1BJ, UK
Bharathram Ganapathisubramani*
Affiliation:
Aerodynamics and Flight Mechanics Group, University of Southampton, SouthamptonSO17 1BJ, UK
*
†Email address for correspondence: [email protected]
Get access Rights & Permissions [Opens in a new window]

Abstract

A synthetic jet issuing into a cross-flow influences the local velocity of the cross-flow. At the jet exit the jet is oriented in the wall-normal direction while the cross-flow is oriented in the streamwise direction, leading to a momentum transfer between the jet and the cross-flow. Streamwise momentum transferred from the cross-flow to the jet accelerates the pulses created by the jet. This momentum transfer continuous up to some point downstream where these pulses have the same velocity as the surrounding flow and are no longer blocking the cross-flow. The momentum transfer from the cross-flow to the jet leads to a momentum deficit in the cross-flow far downstream of the viscous near field of the jet. In the literature this momentum-flux deficit is often attributed to viscous blockage or to up-wash of low-momentum fluid. The present paper proposes and quantifies a third source of momentum deficit: a velocity induced opposite to the cross-flow by the vortical structures created by the synthetic jet. These vortical structures are reconstructed from measured data and their induced velocity is calculated using the Biot–Savart law. The three-dimensional three-component induced velocity fields show great similarity to the measured velocity fields, suggesting that this induced velocity is the main contributor to the velocity field around the synthetic jet and viscous effects have only a small influence. The momentum-flux deficit induced by the vortical structures is compared to the measured momentum-flux deficit, showing that the main part of this deficit is caused by the induced velocity. Variations with Strouhal number (frequency of the jet) and velocity ratio (velocity of the jet) are observed and discussed. An inviscid-flow model is developed, which represents the downstream evolution of the jet in cross-flow. Using the measured data as an input, this model is able to predict the deformation, (wall-normal) evolution and qualitative velocity field of the jet. The present study presents evidence that the velocity induced by the vortical structures forming a synthetic jet plays an important role in the development of and the velocity field around the jet.

JFM classification

Wakes/Jets: Jets Turbulent Flows: Turbulent boundary layers Vortex Flows: Vortex interactions
Type
JFM Papers
Information
Journal of Fluid Mechanics , Volume 870 , 10 July 2019 , pp. 651 - 679
Copyright
© 2019 Cambridge University Press 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Abbassi, M. R., Baars, W., Hutchins, N. & Marusic, I. 2017 Skin-friction drag reduction in a high-Reynolds-number turbulent boundary layer via real-time control of large-scale structures. Intl J. Heat Fluid Flow 67 (B), 30–41.Google Scholar
Adrian, R. J., Christensen, K. T. & Liu, Z. C. 2000 Analysis and interpretation of instantaneous turbulent velocity fields. Exp. Fluids 29 (3), 275–290.Google Scholar
Baidya, R., Philip, J., Hutchins, N., Monty, J. P. & Marusic, I. 2017 Distance-from-the-wall scaling of turbulent motions in wall-bounded flows. Phys. Fluids 29, 020712.Google Scholar
Berk, T., Gomit, G. & Ganapathisubramani, B. 2016 Vectoring of parallel synthetic jets: a parametric study. J. Fluid Mech. 804, 467–489.Google Scholar
Berk, T., Hutchins, N., Marusic, I. & Ganapathisubramani, B. 2018 Trajectory of a synthetic jet issuing into high-reynolds-number turbulent boundary layers. J. Fluid Mech. 856, 531–551.Google Scholar
Broadwell, J. & Breidenthal, R. 1984 Structure and mixing of a transverse jet in incompressible flow. J. Fluid Mech. 148, 405–412.Google Scholar
Cater, J. E. & Soria, J. 2002 The evolution of round zero-net-mass-flux jets. J. Fluid Mech. 472, 167–200.Google Scholar
Cattafesta, L. N. & Sheplak, M. 2011 Actuators for active flow control. Annu. Rev. Fluid Mech. 43 (1), 247–272.Google Scholar
Cheng, M., Lou, J. & Lim, T. T. 2009 Motion of a vortex ring in a simple shear flow. Phys. Fluids 21 (8), 081701.Google Scholar
Cortelezzi, L. & Karagozian, A. R. 2001 On the formation of the counter-rotating vortex pair in transverse jets. J. Fluid Mech. 446, 347–373.Google Scholar
Dandois, J., Garnier, E. & Sagaut, P. 2007 Numerical simulation of active separation control by a synthetic jet. J. Fluid Mech. 574, 25–58.Google Scholar
Eroglu, A. & Breidenthal, R. E. 2001 Structure, penetration, and mixing of pulsed jets in crossflow. AIAA J. 39 (3), 417–423.Google Scholar
Fric, T. & Roshko, A. 1994 Vortical structure in the wake of a transverse jet. J. Fluid Mech. 279, 1–47.Google Scholar
Glezer, A. & Amitay, M. 2002 Synthetic jets. Annu. Rev. Fluid Mech. 34 (1), 503–529.Google Scholar
Holman, R., Utturkar, Y., Mittal, R., Smith, B. L. & Cattafesta, L. 2005 Formation criterion for synthetic jets. AIAA J. 43 (10), 2110–2116.Google Scholar
Jabbal, M. & Zhong, S. 2008 The near wall effect of synthetic jets in a boundary layer. Intl J. Heat Fluid Flow 29 (1), 119–130.Google Scholar
Johari, H. 2006 Scaling of fully pulsed jets in crossflow. AIAA J. 44 (11), 2719–2725.Google Scholar
Kamotani, Y. & Greber, I. 1972 Experiments on a turbulent jet in a cross flow. AIAA J. 10 (11), 1425–1429.Google Scholar
Karagozian, A. R. 2014 The jet in crossflow. Phys. Fluids 26, 101303.Google Scholar
Kelso, R. M., Lim, T. T. & Perry, A. E. 1996 An experimental study of round jets in cross-flow. J. Fluid Mech. 306, 111–144.Google Scholar
Lardeau, S. & Leschziner, M. A. 2011 The interaction of round synthetic jets with a turbulent boundary layer separating from a rounded ramp. J. Fluid Mech. 683, 172–211.Google Scholar
Lim, T. T., Lua, K. B. & Thet, K. Does kutta lift exist on a vortex ring in a uniform cross flow? Phys. Fluids 20 (5), 051701 2008.Google Scholar
Mahesh, K. 2013 The interaction of jets with crossflow. Annu. Rev. Fluid Mech. 45 (1), 379–407.Google Scholar
Marusic, I., Monty, J. P., Hultmark, M. & Smits, A. J. 2013 On the logarithmic region in wall turbulence. J. Fluid Mech. 716, R3.Google Scholar
M’Closkey, R. T., King, J. M., Cortelezzi, L. & Karagozian, A. R. 2002 The actively controlled jet in crossflow. J. Fluid Mech. 452, 325–335.Google Scholar
Moin, P., Leonard, A. & Kim, J. 1986 Evolution of a curved vortex filament into a vortex ring. Phys. Fluids 29, 955–963.Google Scholar
Morton, B. R. & Ibbetson, A. 1996 Jets deflected in a crossflow. Exp. Therm. Fluid Sci. 12, 112–133.Google Scholar
Perry, A. E. & Chong, M. S. 1982 On the mechanism of wall turbulence. J. Fluid Mech. 119, 173–217.Google Scholar
Rathnasingham, R. & Breuer, K. S. 2003 Active control of turbulent boundary layers. J. Fluid Mech. 495, 209–233.Google Scholar
Sau, R. & Mahesh, K. 2008 Dynamics and mixing of vortex rings in crossflow. J. Fluid Mech. 604, 389–409.Google Scholar
Shapiro, S. R., King, J. M., M’Closkey, R. T. & Karagozian, A. R. 2006 Optimization of controlled jets in crossflow. AIAA J. 44 (6), 1292–1298.Google Scholar
Shariff, K. & Leonard, A. 1992 Vortex rings. Annu. Rev. Fluid Mech. 24, 235–279.Google Scholar
Smith, B. L. & Glezer, A. 1998 The formation and evolution of synthetic jets. Phys. Fluids 10 (9), 2281–2297.Google Scholar
Straccia, J. C. & Farnsworth, J. A. N. 2017 Application of a biot-savart solver to predict axis switching phenomenon in finite-span vortices expelled from a synthetic jet. In 47th AIAA Fluid Dynamics Conference, Denver, CO, USA.Google Scholar
Sumner, D., Heseltine, J. L. & Dansereau, O. J. P. 2004 Wake strudcture of a fintie circular cylinder of small aspect ratio. Exp. Fluids 37, 720–730.Google Scholar
de Silva, C. M., Hutchins, N. & Marusic, I. 2015 Uniform momentum zones in turbulent boundary layers. J. Fluid Mech. 786, 309–331.Google Scholar
Van Buren, T., Beyar, M., Leong, C. M. & Amitay, M. 2016a Three-dimensional interaction of a finite-span synthetic jet in a crossflow. Phys. Fluids 28 (3), 037105.Google Scholar
Van Buren, T., Leong, C. M., Whalen, E. & Amitay, M. 2016b Impact of orifice orientation on a finite-span synthetic jet interaction with a crossflow. Phys. Fluids 28, 037106.Google Scholar
Wu, J. M., Vakili, A. D. & Yu, F. M. 1988 Investigation of the interacting flow of nonsymmetric jets in crossflow. AIAA J. 26 (8), 940–947.Google Scholar
Supplementary material: File

Berk and Ganapathisubramani supplementary material

Berk and Ganapathisubramani supplementary material 1

Download Berk and Ganapathisubramani supplementary material(File)
File 4.3 KB