Skip to main content Accessibility help
×
Home

Direct numerical simulation of the turbulent boundary layer over a rod-roughened wall

  • SEUNG-HYUN LEE (a1) and HYUNG JIN SUNG (a1)

Abstract

The effects of surface roughness on a spatially developing turbulent boundary layer (TBL) are investigated by performing direct numerical simulations of TBLs over rough and smooth walls. The Reynolds number based on the momentum thickness was varied in the range Reθ = 300 ∼ 1400. The roughness elements were periodically arranged two-dimensional spanwise rods, and the roughness height was k = 1.5θin, where θin is the momentum thickness at the inlet, which corresponds to k/δ = 0.045 ∼ 0.125, δ being the boundary layer thickness. To avoid generating a rough-wall inflow, which is prohibitively difficult, a step change from smooth to rough was placed 80θin downstream from the inlet. The spatially developing characteristics of the rough-wall TBL were examined. Along the streamwise direction, the friction velocity approached a constant value, and self-preserving forms of the turbulent Reynolds stress tensors were obtained. Introduction of the roughness elements affected the turbulent stress not only in the roughness sublayer but also in the outer layer. Despite the roughness-induced increase of the turbulent Reynolds stress tensors in the outer layer, the roughness had only a relatively small effect on the anisotropic Reynolds stress tensor in the outer layer. Inspection of the triple products of the velocity fluctuations revealed that introducing the roughness elements onto the smooth wall had a marked effect on vertical turbulent transport across the whole TBL. By contrast, good surface similarity in the outer layer was obtained for the third-order moments of the velocity fluctuations.

Copyright

Corresponding author

Author to whom correspondence should be addressed: hjsung@kaist.ac.kr

References

Hide All
Andreopoulos, J. & Bradshaw, P. 1981 Measurements of turbulence structure in the boundary layer on a rough surface. Boundary-Layer Met. 20, 201213.
Antonia, R. A. & Krogstad, P.-Å. 2001 Turbulence structure in boundary layers over different types of surface roughness. Fluid Dyn. Res. 28, 139157.
Antonia, R. A. & Luxton, R. E. 1971 The response of a turbulent boundary layer to a step change in surface roughness Part 1. Smooth to rough. J. Fluid Mech. 48, 721761.
Ashrafian, A., Andersson, H. I. & Manhart, M. 2004 DNS of turbulent flow in a rod-roughened channel. Intl. J. Heat Fluid Flow 25, 373383.
Ashrafian, A. & Andersson, H. I. 2006 a The structure of turbulence in a rod-roughened channel. Intl J. Heat Fluid Flow 27, 6579.
Ashrafian, A. & Andersson, H. I. 2006 b Roughness effects in turbulent channel flow. Prog. Comput. Fluid Dyn. 6, 120.
Bakken, O. M. & Krogstad, P.-Å., Ashrafian, A. & Andersson, H. I. 2005 Reynolds number effects in the outer layer of the turbulent flow in a channel with rough walls Phys. Fluids 17, 065101.
Bandyopadhyay, P. R. & Watson, R. D. 1988 Structure of rough-wall boundary layers. Phys. Fluids 31, 18771883.
Bhaganagar, K., Kim, J. & Coleman, G. 2004 Effect of roughness on wall-bounded turbulence. Flow, Turbulence Combust. 72, 463492.
Bisceglia, S., Smalley, R. J., Antonia, R. A. & Djenidi, L. 2001 Rough-wall turbulent boundary layers at relatively high Reynolds number. Proc. 14th Australasian Fluid Mechanics Conference, vol. 1, pp. 195–198.
Connelly, J. S., Schultz, M. P. & Flack, K. A. 2006 Velocity-defect scaling for turbulent boundary layers with a range of relative roughness. Exps. Fluids 40, 188195.
Djenidi, L., Elavarasan, R. & Antonia, R. A. 1999 The turbulent boundary layer over transverse square cavities. J. Fluid Mech. 395, 271294.
Flack, K. A., Schultz, M. P. & Shapiro, T. A. 2005 Experimental support for Townsend's Reynolds number similarity. Phys. Fluids 17, 035102.
Grass, A. J., Stuart, R. J. & Mansor-Tehrani, M. 1993 Common vortical structure of turbulent flows over smooth and rough boundaries. AIAA J. 31, 837847.
Jackson, P. S. 1981 On the displacement height in the logarithmic profiles. J. Fluid Mech. 111, 1525.
Jimenez, J. 2004 Turbulent flows over rough walls. Annu. Rev. Fluid Mech. 36, 173196.
Keirsbulck, L., Labraga, L., Mazouz, A. & Tournier, C. 2002 a Surface roughness effects on turbulent boundary layer structures. Trans. ASME: J. Fluids Engng 124, 127135.
Keirsbulck, L., Labraga, L., Mazouz, A. & Tournier, C. 2002 b Influence of surface roughness on anisotropy boundary layer flow. Exps. Fluids 33, 497499.
Kim, J., Kim, D. & Choi, H. 2001 An immersed boundary finite-volume method for simulations of flow in complex geometries. J. Comput. Phys. 171, 132150.
Kim, K., Baek, S.-J. & Sung, H. J. 2002 An implicit velocity decoupling procedure for the incompressible Navier-Stokes equations. Intl. J. Numer. Meth. Fluids 38, 125138.
Krogstad, P.-Å., Antonia, R. A. & Browne, L. W. B. 1992 Comparison between rough- and smooth-wall turbulent boundary layers. J. Fluid Mech. 245, 599617.
Krogstad, P.-Å. & Antonia, R. A. 1994 Structure of turbulent boundary layers on smooth and rough walls. J. Fluid Mech. 277, 121.
Krogstad, P.-Å. & Antonia, R. A. 1999 Surface roughness effects in turbulent boundary layers. Exps. Fluids 27, 450460.
Krogstad, P.-Å., Andersson, H. I., Bakken, O. M. & Ashrafian, A. 2005 An experimental and numerical study of channel flow with rough walls. J. Fluid Mech. 530, 327352.
Lee, C. 2002 Large-eddy simulation of rough-wall turbulent boundary layers. AIAA J. 40, 21272130.
Leonardi, S., Orlandi, P., Smalley, R. J., Djenidi, L. & Antonia, R. A. 2003 Direct numerical simulations of turbulent channel flow with transverse square bars on one wall. J. Fluid Mech. 491, 229238.
Lund, T. S., Wu, X. & Squires, K. D. 1998 Generation of turbulent inflow data for spatially-developing boundary layer simulation. J. Comput. Phys. 140, 233258.
Mazouz, A., Labraga, L. & Tournier, C. 1998 Anisotropy invariants of Reynolds stress tensor in a duct flow and turbulent boundary layer. Trans. ASME: J. Fluids Engng 120, 280284.
Raupach, M. R., Antonia, R. A. & Rajagopalan, S. 1991 Rough-wall turbulent boundary layers. Appl. Mech. Rev. 44, 125.
Sabot, J., Saleh, I. & Compte-Bellot, G. 1977 Effects of roughness on the intermittent maintenance of Reynolds shear stress in pipe flow. Phys. Fluids 20, S150S155.
Schultz, M. P. & Flack, K. A. 2003 Turbulent boundary layers over surfaces smoothed by sanding. Trans. ASME: J. Fluids Engng 125, 863870.
Schultz, M. P. & Flack, K. A. 2005 Outer layer similarity in fully rough turbulent boundary layers. Exps. Fluids 38, 328340.
Shafi, H. S. & Antonia, R. A. 1995 Anisotropy of the Reynolds stresses in a turbulent boundary layer on a rough wall. Exps. Fluids 18, 213215.
Smalley, R. J., Antonia, R. A. & Djenidi, L. 2001 Self-preservation of rough-wall turbulent boundary layers. Eur. J. Mech. B-Fluids 20, 591602.
Smalley, R. J., Leonardi, S., Antonia, R. A., Djenidi, L. & Orlandi, P. 2002 Reynolds stress anisotropy of turbulent rough wall layers. Exps. Fluids 33, 3237.
Spalart, P. R. 1988 Direct simulation of a turbulent boundary layer up to Re θ = 1410. J. Fluid Mech. 187, 6198.
Townsend, A. A. 1976 The Structure of Turbulent Shear Flow. Cambridge University Press.
MathJax
MathJax is a JavaScript display engine for mathematics. For more information see http://www.mathjax.org.

Related content

Powered by UNSILO

Direct numerical simulation of the turbulent boundary layer over a rod-roughened wall

  • SEUNG-HYUN LEE (a1) and HYUNG JIN SUNG (a1)

Metrics

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed.