Hostname: page-component-cd9895bd7-hc48f Total loading time: 0 Render date: 2024-12-28T21:56:05.545Z Has data issue: false hasContentIssue false
  • English
  • Français

Investigation of the influence of miniature vortex generators on the large-scale motions of a turbulent boundary layer

Published online by Cambridge University Press:  07 December 2021

C.I. Chan Open the ORCID record for C.I. Chan [Opens in a new window]  and
R.C. Chin Open the ORCID record for R.C. Chin [Opens in a new window]
C.I. Chan*
Affiliation:
School of Mechanical Engineering, University of Adelaide, South Australia5005, Australia
R.C. Chin
Affiliation:
School of Mechanical Engineering, University of Adelaide, South Australia5005, Australia
*
†Email address for correspondence: chiip.chan@adelaide.edu.au
Get access Rights & Permissions [Opens in a new window]

Abstract

Well resolved large-eddy simulation data are used to study the physical modulation effects of miniature vortex generators (MVGs) in a moderate Reynolds number zero pressure gradient turbulent boundary layer. Large-scale counter-rotating primary vortex pairs (PVPs) imposed by the MVG contribute to the formation of streamwise streaks by transporting high momentum fluids from the outer regions of the boundary layer towards the wall, giving rise to high-speed regions centred at the PVP. Consequently, low-speed regions are formed along the outer flank of the PVP, resulting in a pronounced alternating high- and low-speed flow pattern. The PVP also relates to regions with skin friction modification, where a local skin friction reduction of up to 15 % is obtained at the low-speed region, but the opposite situation is observed over the high-speed region. The MVG-induced flow feature is further investigated by spectral analysis of the triple decomposition velocity fluctuation. Pre-multiplied energy spectra of the streamwise MVG-induced velocity fluctuation reveal that the large-scale induced modes scale with the spanwise wavelength and the length of the MVG, but the energy peak is eventually repositioned to the size of the near-wall streaks in the streamwise direction. Analysis of the triple decomposition of the kinetic energy transport equations revealed the significance of the mean flow gradient in generating kinetic energy which sustains the secondary motion. There is also an energy transfer between the turbulent and MVG-induced kinetic energy independent of the mean flow.

JFM classification

Boundary Layers: Boundary layer control Turbulent Flows: Turbulence control
Type
JFM Papers
Information
Journal of Fluid Mechanics , Volume 932 , 10 February 2022 , A29
Check for updates
Copyright
© The Author(s), 2021. Published by 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

REFERENCES

del Álamo, J.C. & Jiménez, J. 2009 Estimation of turbulent convection velocities and corrections to Taylor's approximation. J. Fluid Mech. 640, 5–26.CrossRefGoogle Scholar
Brynjell-Rahkola, M., Schlatter, P., Hanifi, A. & Henningson, D.S. 2015 Global stability analysis of a roughness wake in a Falkner–Skan–Cooke boundary layer. Procedia IUTAM 14, 192–200.CrossRefGoogle Scholar
Camarri, S., Fransson, J.H.M. & Talamelli, A. 2014 Numerical investigation of the afrodite transition control strategy. In Progress in Turbulence V, pp. 65–69. Springer.CrossRefGoogle Scholar
Canton, J., Örlü, R., Chin, C. & Schlatter, P. 2016 Reynolds number dependence of large-scale friction control in turbulent channel flow. Phys. Rev. Fluids 1, 081501.CrossRefGoogle Scholar
Chan, C.I., Schlatter, P. & Chin, R.C. 2021 Interscale transport mechanisms in turbulent boundary layers. J. Fluid Mech. 921, A13.CrossRefGoogle Scholar
Chevalier, M., Lundbladh, A. & Henningson, D.S. 2007 Simson–a pseudo-spectral solver for incompressible boundary layer flow. Tech. Rep. TRITA-MEK 2007:07. KTH Mechanics, Stockholm, Sweden.Google Scholar
Chin, C., Örlü, R., Monty, J., Hutchins, N., Ooi, A. & Schlatter, P. 2017 Simulation of a large-eddy-break-up device (LEBU) in a moderate Reynolds number turbulent boundary layer. Flow Turbul. Combust. 98 (2), 445–460.CrossRefGoogle Scholar
Eitel-Amor, G., Örlü, R. & Schlatter, P. 2014 Simulation and validation of a spatially evolving turbulent boundary layer up to $Re_\theta =8300$. Intl J. Heat Fluid Flow 47, 57–69.CrossRefGoogle Scholar
Fransson, J.H.M., Brandt, L., Talamelli, A. & Cossu, C. 2005 Experimental study of the stabilization of Tollmien–Schlichting waves by finite amplitude streaks. Phys. Fluids 17 (5), 054110.CrossRefGoogle Scholar
Fransson, J.H.M. & Talamelli, A. 2012 On the generation of steady streamwise streaks in flat-plate boundary layers. J. Fluid Mech. 698, 211–234.CrossRefGoogle Scholar
Fransson, J.H.M., Talamelli, A., Brandt, L. & Cossu, C. 2006 Delaying transition to turbulence by a passive mechanism. Phys. Rev. Lett. 96, 064501.CrossRefGoogle ScholarPubMed
Hamilton, J.M., Kim, J. & Waleffe, F. 1995 Regeneration mechanisms of near-wall turbulence structures. J. Fluid Mech. 287, 317–348.CrossRefGoogle Scholar
Hutchins, N. & Marusic, I. 2007 a Evidence of very long meandering features in the logarithmic region of turbulent boundary layers. J. Fluid Mech. 579, 1–28.CrossRefGoogle Scholar
Hutchins, N. & Marusic, I. 2007 b Large-scale influences in near-wall turbulence. Phil. Trans. R. Soc. Lond. A 365 (1852), 647–664.Google ScholarPubMed
Jeong, J. & Hussain, F. 1995 On the identification of a vortex. J. Fluid Mech. 285, 69–94.CrossRefGoogle Scholar
Jiménez, J. & Pinelli, A. 1999 The autonomous cycle of near-wall turbulence. J. Fluid Mech. 389, 335–359.CrossRefGoogle Scholar
Kline, S.J., Reynolds, W.C., Schraub, F.A. & Runstadler, P.W. 1967 The structure of turbulent boundary layers. J. Fluid Mech. 30, 741–773.CrossRefGoogle Scholar
Landahl, M.T. 1980 A note on an algebraic instability of inviscid parallel shear flows. J. Fluid Mech. 98 (2), 243–251.CrossRefGoogle Scholar
Lee, M. & Moser, R.D. 2015 Direct numerical simulation of turbulent channel flow up to $Re_\tau \approx 5200$. J. Fluid Mech. 774, 395–415.CrossRefGoogle Scholar
Li, Q., Schlatter, P. & Henningson, D.S. 2008 Spectral simulations of wall-bounded flows on massively parallel computers. Tech. Rep. KTH Mechanics, Stockholm, Sweden.Google Scholar
Lin, J. 2002 Review of research on low-profile vortex generators to control boundary-layer separation. Prog. Aerospace Sci. 38 (4), 389–420.CrossRefGoogle Scholar
Lögdberg, O. 2006 Vortex generators and turbulent boundary layer separation control. Licentiate thesis, Department of Mechanics, KTH, Stockholm.Google Scholar
Lögdberg, O., Fransson, J.H.M. & Alfredsson, P.H. 2009 Streamwise evolution of longitudinal vortices in a turbulent boundary layer. J. Fluid Mech. 623, 27–58.CrossRefGoogle Scholar
Mathis, R., Hutchins, N. & Marusic, I. 2009 Large-scale amplitude modulation of the small-scale structures in turbulent boundary layers. J. Fluid Mech. 628, 311–337.CrossRefGoogle Scholar
Österlund, J.M. 1999 Experimental studies of zero pressure-gradient turbulent boundary layer flow. PhD thesis, KTH, Mechanics.Google Scholar
Panton, R.L. 2001 Overview of the self-sustaining mechanisms of wall turbulence. Prog. Aerosp. Sci. 37 (4), 341–383.CrossRefGoogle Scholar
Pope, S.B. 2000 Turbulent Flows. Cambridge University Press.CrossRefGoogle Scholar
Reynolds, W.C. & Hussain, A.K.M.F. 1972 The mechanics of an organized wave in turbulent shear flow. Part 3. Theoretical models and comparisons with experiments. J. Fluid Mech. 54 (2), 263–288.CrossRefGoogle Scholar
Sattarzadeh, S.S. & Fransson, J.H.M. 2015 On the scaling of streamwise streaks and their efficiency to attenuate Tollmien–Schlichting waves. Exp. Fluids 56 (3), 1–16.CrossRefGoogle Scholar
Sattarzadeh, S.S., Fransson, J.H.M., Talamelli, A. & Fallenius, B.E.G. 2014 Consecutive turbulence transition delay with reinforced passive control. Phys. Rev. E 89, 061001.CrossRefGoogle ScholarPubMed
Schlatter, P., Li, Q., Brethouwer, G., Johansson, A.V. & Henningson, D.S. 2010 Simulations of spatially evolving turbulent boundary layers up to $Re_\theta =4300$. Intl J. Heat Fluid Flow 31 (3), 251–261.CrossRefGoogle Scholar
Schlatter, P. & Örlü, R. 2010 Assessment of direct numerical simulation data of turbulent boundary layers. J. Fluid Mech. 659, 116–126.CrossRefGoogle Scholar
Schlatter, P. & Örlü, R. 2012 Turbulent boundary layers at moderate Reynolds numbers: inflow length and tripping effects. J. Fluid Mech. 710, 5–34.CrossRefGoogle Scholar
Schlatter, P., Stolz, S. & Kleiser, L. 2004 LES of transitional flows using the approximate deconvolution model. Intl J. Heat Fluid Flow 25 (3), 549–558.CrossRefGoogle Scholar
Shahinfar, S., Fransson, J.H.M., Sattarzadeh, S.S. & Talamelli, A. 2013 Scaling of streamwise boundary layer streaks and their ability to reduce skin-friction drag. J. Fluid Mech. 733, 1–32.CrossRefGoogle Scholar
Shahinfar, S., Sattarzadeh, S.S. & Fransson, J.H.M. 2014 Passive boundary layer control of oblique disturbances by finite-amplitude streaks. J. Fluid Mech. 749, 1–36.CrossRefGoogle Scholar
Shahinfar, S., Sattarzadeh, S.S., Fransson, J.H.M. & Talamelli, A. 2012 Revival of classical vortex generators now for transition delay. Phys. Rev. Lett. 109, 074501.CrossRefGoogle ScholarPubMed
Siconolfi, L., Camarri, S. & Fransson, J.H.M. 2015 a Boundary layer stabilization using free-stream vortices. J. Fluid Mech. 764, R2.CrossRefGoogle Scholar
Siconolfi, L., Camarri, S. & Fransson, J.H.M. 2015 b Stability analysis of boundary layers controlled by miniature vortex generators. J. Fluid Mech. 784, 596–618.CrossRefGoogle Scholar
Smits, A.J., Matheson, N. & Joubert, P.N. 1983 Low-Reynolds-number turbulent boundary layers in zero and favourable pressure gradients. J. Ship Res. 27, 147–157.CrossRefGoogle Scholar
Stolz, S., Adams, N.A. & Kleiser, L. 2001 An approximate deconvolution model for large-eddy simulation with application to incompressible wall-bounded flows. Phys. Fluids 13 (4), 997–1015.CrossRefGoogle Scholar
Tomkins, C.D. & Adrian, R.J. 2003 Spanwise structure and scale growth in turbulent boundary layers. J. Fluid Mech. 490, 37–74.CrossRefGoogle Scholar