Hostname: page-component-8448b6f56d-jr42d Total loading time: 0 Render date: 2024-04-20T02:08:11.846Z Has data issue: false hasContentIssue false
  • English
  • Français

Transition to turbulence over 2D and 3D periodic large-scale roughnesses

Published online by Cambridge University Press:  08 September 2016

A. M. Hamed ,
M. Sadowski ,
Z. Zhang  and
L. P. Chamorro
A. M. Hamed
Affiliation:
Department of Mechanical Science and Engineering, University of Illinois, Urbana, IL 61801, USA
M. Sadowski
Affiliation:
Department of Mechanical Science and Engineering, University of Illinois, Urbana, IL 61801, USA
Z. Zhang
Affiliation:
Department of Mechanical Science and Engineering, University of Illinois, Urbana, IL 61801, USA
L. P. Chamorro*
Affiliation:
Department of Mechanical Science and Engineering, University of Illinois, Urbana, IL 61801, USA Department of Civil and Environmental Engineering, University of Illinois, Urbana, IL 61801, USA Department of Aerospace Engineering, University of Illinois, Urbana, IL 61801, USA
*
†Email address for correspondence: lpchamo@illinois.edu
Get access Rights & Permissions [Opens in a new window]

Abstract

A laboratory investigation was performed to study distinctive features of the laminar-to-turbulent transition over distributed roughness characterized by two-dimensional (2D) and three-dimensional (3D) periodic, low-order topographies at roughness Reynolds number $Re_{k}\approx 300$. Systematic experiments were performed using high-spatial-resolution planar particle image velocimetry (PIV) in a refractive-index-matching (RIM) channel, where the roughness covered the entire length of the test section. The results show that the flow over the 2D roughness becomes turbulent much sooner than its 3D counterpart ($Re_{x}=50\,000$ versus 120 000). This is attributed to the presence of a velocity inflection point resulting from flow separation within the troughs of the 2D roughness. In the transitional region, unsteady disturbances above the two roughnesses appear upstream of near-roughness disturbances. The above-roughness disturbances are associated with the inflection point in the vertically displaced boundary layer for the 2D case, and with the mean velocity deficit resulting from the interaction of the wakes of upstream elements for the 3D case. The near-roughness fluctuations are associated with the shear layer present behind the crests of both roughnesses. The transitional region is characterized by the interaction between above- and near-roughness disturbances, which merge, leading to a rapid vertical growth of the turbulent fluctuations.

JFM classification

Instability: Instability Instability: Transition to turbulence
Type
Rapids
Information
Journal of Fluid Mechanics , Volume 804 , 10 October 2016 , R6
Check for updates
Copyright
© 2016 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

Bai, K. & Katz, J. 2014 On the refractive index of sodium iodide solutions for index matching in PIV. Exp. Fluids 55, 1–6.Google Scholar
Berkooz, G., Holmes, P. & Lumley, J. L. 1993 The proper orthogonal decomposition in the analysis of turbulent flows. Annu. Rev. Fluid Mech. 25 (1), 539–575.Google Scholar
Bernardini, M., Pirozzoli, S., Orlandi, P. & Lele, S. K. 2014 Parameterization of boundary-layer transition induced by isolated roughness elements. AIAA J. 52 (10), 2261–2269.Google Scholar
Blois, G., Christensen, K. T., Best, J. L., Elliott, G., Austin, J., Dutton, C., Bragg, M., Garcia, M. & Fouke, B. 2012 A versatile refractive-index-matched flow facility for studies of complex flow systems across scientific disciplines. In 50th American Institute of Aeronautics and Astronautics (AIAA) Aerospace Sciences Meeting, Nashville, TN, AIAA Paper 2012–0736.Google Scholar
Choi, K. 2006 Fluid dynamics: the rough with the smooth. Nature 440 (7085), 754–754.Google Scholar
Cossu, C. & Brandt, L. 2002 Stabilization of Tollmien–Schlichting waves by finite amplitude optimal streaks in the Blasius boundary layer. Phys. Fluids 14 (8), L57–L60.Google Scholar
Downs, R. S., White, E. B. & Denissen, N. A. 2008 Transient growth and transition induced by random distributed roughness. AIAA J. 46 (2), 451–462.Google Scholar
Drews, S. D.2012 Direct numerical simulations of flow past quasi-random distributed roughness. Master’s thesis, University of Texas at Austin.Google Scholar
Drews, S. D., Downs, R. S., Doolittle, C. J., Goldstein, D. & White, E. B.2011 Direct numerical simulations of flow past random distributed roughness. AIAA Paper 2011-564.Google Scholar
Dryden, H. L. 1953 Review of published data on the effect of roughness on transition from laminar to turbulent flow. J. Aero. Sci. 20 (7), 477–482.Google Scholar
Edelmann, C. A. & Rist, U. 2015 Impact of forward-facing steps on laminar–turbulent transition in transonic flows. AIAA J. 53 (9), 2504–2511.Google Scholar
Ergin, F. G. & White, E. B. 2006 Unsteady and transitional flows behind roughness elements. AIAA J. 44 (11), 2504–2514.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 (6), 064501.Google Scholar
Goldstein, M. E. 1985 Scattering of acoustic waves into Tollmien–Schlichting waves by small streamwise variations in surface geometry. J. Fluid Mech. 154, 509–529.Google Scholar
Hamed, A. M., Kamdar, A., Castillo, L. & Chamorro, L. P. 2015 Turbulent boundary layer over 2d and 3d large-scale wavy walls. Phys. Fluids 27 (10), 106601.Google Scholar
Klebanoff, P. S., Schubauer, G. B. & Tidstrom, K. D. 1955 Measurements of the effect of 2-dimensional and 3-dimensional roughness elements on boundary-layer transition. J. Aero. Sci. 22 (11), 803–804.Google Scholar
Klebanoff, P. S. & Tidstrom, K. D. 1972 Mechanism by which a two-dimensional roughness element induces boundary-layer transition. Phys. Fluids 15 (7), 1173–1188.Google Scholar
Kuester, M. S. & White, E. B. 2015 Roughness receptivity and shielding in a flat plate boundary layer. J. Fluid Mech. 777, 430–460.Google Scholar
Lumley, J. 1970 Stochastic Tools in Turbulence. Academic.Google Scholar
Plogmann, B., Würz, W. & Krämer, E. 2014 On the disturbance evolution downstream of a cylindrical roughness element. J. Fluid Mech. 758, 238–286.Google Scholar
Reshotko, E. 2001 Transient growth: a factor in bypass transition. Phys. Fluids 13 (5), 1067–1075.CrossRefGoogle Scholar
Reshotko, E. & Tumin, A. 2004 Role of transient growth in roughness-induced transition. AIAA J. 42 (4), 766–770.Google 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.Google 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 (7), 074501.Google Scholar
Sirovich, L. 1987 Turbulence and the dynamics of coherent structures. Part I: coherent structures. Q. Appl. Maths 45 (3), 561–571.Google Scholar
Smith, A. & Clutter, D. W. 1959 The smallest height of roughness capable of affecting boundary-layer transition. J. Aero. Sci. 26, 229–245.Google Scholar
Tani, I. 1969 Boundary-layer transition. Annu. Rev. Fluid Mech. 1 (1), 169–196.Google Scholar
Ye, Q., Schrijer, F. F. J. & Scarano, F. 2016 Boundary layer transition mechanisms behind a micro-ramp. J. Fluid Mech. 793, 132–161.Google Scholar