Hostname: page-component-586b7cd67f-g8jcs Total loading time: 0 Render date: 2024-12-03T00:44:09.010Z Has data issue: false hasContentIssue false

Representing surface roughness in eddy resolving simulation

Published online by Cambridge University Press:  09 June 2020

Joel Varghese*
Affiliation:
Department of Aerospace Engineering, Iowa State University, Ames, IA50011, USA
Paul A. Durbin
Affiliation:
Department of Aerospace Engineering, Iowa State University, Ames, IA50011, USA
*
Email address for correspondence: [email protected]

Abstract

The motive behind the present paper is to investigate a method for representing the effect of surface roughness in eddy resolving simulations of turbulent flow, without including the geometric form of the roughness as a boundary. It is found that introducing a drag force, quadratic in a reference velocity, and confined to a zone next to the wall, is remarkably possible to capture the dominant effects of roughness. The drag representation is not new; indeed, it is motivated by Reynolds averaged models. The present assessment provides a new perspective on the fluid dynamical action of distributed roughness: its dominant effect is not to create eddies in the wake of asperities, or to provide a geometric obstruction. The drag model, with no geometrical features, suppresses streaks that occur over smooth walls, and generates large, outer region eddies, in a quite similar way to resolved roughness. In a sense, this is an expanded perspective on Townsend’s hypothesis. As in that hypothesis, Reynolds stresses scale on friction velocity; but, expanding on the original hypothesis, spectra over the forcing layer agree closely with those over resolved roughness, when the force is calibrated to produce the same friction Reynolds number as the resolved roughness.

Type
JFM Papers
Copyright
© The Author(s), 2020. 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

Busse, A. & Sandham, N. D. 2012 Parametric forcing approach to rough-wall turbulent channel flow. J. Fluid Mech. 712, 169202.CrossRefGoogle Scholar
Chung, D., Monty, J. & Ooi, A. 2014 An idealised assessment of Townsends outer-layer similarity hypothesis for wall turbulence. J. Fluid Mech. 742, R3.CrossRefGoogle Scholar
De Graaff, D. B. & Eaton, J. K. 2000 Reynolds-number scaling of the flat-plate turbulent boundary layer. J. Fluid Mech. 422, 319346.CrossRefGoogle Scholar
Flack, K. A. & Schultz, M. P. 2010 Review of hydraulic roughness scales in the fully rough regime. J. Fluids Engng 132 (4), 041203.CrossRefGoogle Scholar
Flack, K. A., Schultz, M. P. & Shapiro, T. A. 2005 Experimental support for Townsend’s Reynolds number similarity hypothesis on rough walls. Phys. Fluids 17 (3), 035102.CrossRefGoogle Scholar
Ikeda, T. & Durbin, P. A. 2007 Direct simulations of a rough-wall channel flow. J. Fluid Mech. 571, 235263.CrossRefGoogle Scholar
Ismail, U.2018 Simulations of non-equilibrium rough-wall flows. PhD thesis, Iowa State University.Google Scholar
Ismail, U., Zaki, T. A. & Durbin, P. A. 2018a The effect of cube-roughened walls on the response of rough-to-smooth (RTS) turbulent channel flows. Intl J. Heat Fluid Flow 72, 174185.CrossRefGoogle Scholar
Ismail, U., Zaki, T. A. & Durbin, P. A. 2018b Simulations of rib-roughened rough-to-smooth turbulent channel flows. J. Fluid Mech. 843, 419449.CrossRefGoogle Scholar
Knopp, T., Eisfeld, B. & Calvo, J. B. 2009 A new extension for k–𝜔 turbulence models to account for wall roughness. Intl J. Heat Fluid Flow 30 (1), 5465.CrossRefGoogle Scholar
Krumbein, B., Forooghi, P., Jakirlić, S., Magagnato, F. & Frohnapfel, B. 2017 VLES modeling of flow over walls with variably-shaped roughness by reference to complementary DNS. Flow Turbul. Combust. 99 (3–4), 685703.CrossRefGoogle Scholar
Lee, M. & Moser, R. D. 2015 Direct numerical simulation of turbulent channel flow up to Re 𝜏 ≈ 5200. J. Fluid Mech. 774, 395415.CrossRefGoogle Scholar
Leonardi, S. & Castro, I. P. 2010 Channel flow over large cube roughness: a direct numerical simulation study. J. Fluid Mech. 651, 519539.CrossRefGoogle Scholar
Leonardi, S., Orlandi, P., Smalley, R., Djenidi, L. & Antonia, R. 2003 Direct numerical simulations of turbulent channel flow with transverse square bars on one wall. J. Fluid Mech. 491, 229238.CrossRefGoogle Scholar
MacDonald, M., Chung, D., Hutchins, N., Chan, L., Ooi, A. & García-Mayoral, R. 2017 The minimal-span channel for rough-wall turbulent flows. J. Fluid Mech. 816, 542.CrossRefGoogle Scholar
Nikuradse, J. 1950 Laws of Flow in Rough Pipes. National Advisory Committee for Aeronautics Washington.Google Scholar
Orlandi, P. & Leonardi, S. 2006 DNS of turbulent channel flows with two-and three-dimensional roughness. J. Turbul. 7, N73.CrossRefGoogle Scholar
Reddy, K., Ryon, J. & Durbin, P. 2014 A ddes model with a Smagorinsky-type eddy viscosity formulation and log-layer mismatch correction. Intl J. Heat Fluid Flow 50, 103113.CrossRefGoogle Scholar
Sen, M., Bhaganagar, K. & Juttijudata, V. 2007 Application of proper orthogonal decomposition (pod) to investigate a turbulent boundary layer in a channel with rough walls. J. Turbul. 8, N41.CrossRefGoogle Scholar
Shaw, R. & Schumann, U. 1992 Large-eddy simulation of turbulent flow above and within a forest. Boundary-Layer Meteorol. 61 (1), 4764.CrossRefGoogle Scholar
Sirovich, L. 1987 Turbulence and the dynamics of coherent structures. I. Coherent structures. Q. Appl. Maths 45 (3), 561571.CrossRefGoogle Scholar
Stripf, M., Schulz, A., Bauer, H.-J. & Wittig, S. 2009 Extended models for transitional rough wall boundary layers with heat transfer–part I: model formulations. Trans. ASME J. Turbomach. 131 (3), 031016.Google Scholar
Townsend, A. A. 1976 The Structure of Turbulent Shear Flow, 2nd edn. Cambridge University Press.Google Scholar
Volino, R., Schultz, M. & Flack, K. 2007 Turbulence structure in rough-and smooth-wall boundary layers. J. Fluid Mech. 592, 263293.CrossRefGoogle Scholar
Yang, X. I. A., Sadique, J., Mittal, R. & Meneveau, C. 2016 Exponential roughness layer and analytical model for turbulent boundary layer flow over rectangular-prism roughness elements. J. Fluid Mech. 789, 127165.CrossRefGoogle Scholar
Yin, Z. & Durbin, P. A. 2016 An adaptive DES smodel that allows wall-resolved eddy simulation. Intl J. Heat Fluid Flow 62, 499509.CrossRefGoogle Scholar
Yue, W., Parlange, M., Meneveau, C., Zhu, W., van Hout, R. & Katz, J. 2007 Large-eddy simulation of plant canopy flows using plant-scale representation. Boundary-Layer Meteorol. 124 (2), 183203.CrossRefGoogle Scholar