Jump to ContentJump to Main Navigation
Show Summary Details
In This Section

Acta Geophysica

6 Issues per year


IMPACT FACTOR 2016: 0.968
5-year IMPACT FACTOR: 1.270

Cite Score 2016: 1.06

SCImago Journal Rank (SJR) 2015: 0.581
Source Normalized Impact per Paper (SNIP) 2015: 0.779

Open Access
Online
ISSN
1895-7455
See all formats and pricing
In This Section
Volume 56, Issue 3 (Sep 2008)

Issues

Spatially-averaged flow statistics within a canopy of large bluff bodies: Results from direct numerical simulations

Omduth Coceal
  • Department of Meteorology, University of Reading, Reading, UK
  • Email:
/ T. Thomas
  • School of Engineering Sciences, University of Southampton, Highfield, Southampton, UK
  • Email:
/ Stephen Belcher
  • Department of Meteorology, University of Reading, Reading, UK
  • Email:
Published Online: 2008-07-01 | DOI: https://doi.org/10.2478/s11600-008-0025-y

Abstract

The flow within a canopy of large bluff bodies is highly turbulent and spatially heterogeneous. Results from direct numerical simulations over groups of cubical obstacles are analysed using the double-averaging methodology. The obstacles occupy a significant fraction of the canopy space; this gives rise to substantial dispersive stresses within the canopy. The underlying bluff-body turbulent dynamics is different from typical canopy turbulence, and this is reflected in the double-averaged statistics. The spatially-averaged velocities, stresses and drag force depend significantly upon the layout of the obstacles. An ongoing challenge is to parameterise these spatially-averaged quantities in terms of the obstacle geometry and layout.

Keywords: bluff bodies; direct numerical simulations; double-averaging methodology; rough-wall channel flow; turbulent channel flow

  • [1] Belcher, S.E. (2005), Mixing and transport in urban areas, Phil. Trans. Roy. Soc. 363, 2947–2963. http://dx.doi.org/10.1098/rsta.2005.1673 [Crossref]

  • [2] Belcher, S.E., N. Jerram and J.C.R. Hunt (2003), Adjustment of the atmospheric boundary layer to a canopy of roughness elements, J. Fluid Mechanics 488, 369–398. http://dx.doi.org/10.1017/S0022112003005019 [Crossref]

  • [3] Bohm, M., J.J. Finnigan and M.R. Raupach (2000), Dispersive fluxes in canopy flows: Just how important are they? Proc. 24 th Conference on Agricultural and Forest Meteorology, American Meteorological Society, Davis, CA.

  • [4] Castro, I.P., and A.G. Robins (1977), The flow around a surface-mounted cube in uniform and turbulent streams, J. Fluid Mechanics 79, 307–335. http://dx.doi.org/10.1017/S0022112077000172 [Crossref]

  • [5] Cheng, H., and I.P. Castro (2002), Near wall flow over urban-like roughness, Bound.-Layer Meteor. 104, 229–259. http://dx.doi.org/10.1023/A:1016060103448 [Crossref]

  • [6] Cionco, R.M. (1965), A mathematical model for air flow in a vegetative canopy, J. Appl. Meteorol. 4, 517–522. http://dx.doi.org/10.1175/1520-0450(1965)004<0517:AMMFAF>2.0.CO;2 [Crossref]

  • [7] Coceal, O., and S.E. Belcher (2004), A canopy model of mean winds through urban areas, Quart. J. Roy. Met. Soc. 130, 1349–1372. http://dx.doi.org/10.1256/qj.03.40 [Crossref]

  • [8] Coceal, O., and S.E. Belcher (2005), Mean winds through an inhomogeneous urban canopy, Bound.-Layer Meteor. 115, 47–68. http://dx.doi.org/10.1007/s10546-004-1591-4 [Crossref]

  • [9] Coceal, O., T.G. Thomas, I.P. Castro and S.E. Belcher (2006), Mean flow and turbulence statistics over groups of urban-like cubical obstacles, Bound.-Layer Meteor. 121, 491–519. http://dx.doi.org/10.1007/s10546-006-9076-2 [Crossref]

  • [10] Coceal, O., A. Dobre, and T.G. Thomas (2007a), Unsteady dynamics and organized structures from DNS over an idealized building canopy, Int. J. Climatol. 27, 1943–1953. http://dx.doi.org/10.1002/joc.1549 [Web of Science] [Crossref]

  • [11] Coceal, O., A. Dobre, T.G. Thomas, and S.E. Belcher (2007b), Structure of turbulent flow overregular arrays of cubical roughness, J. Fluid Mechanics 589, 375–409. http://dx.doi.org/10.1017/S002211200700794X [Crossref]

  • [12] Finnigan, J.J. (2000), Turbulence in plant canopies, Ann. Rev. Fluid Mech. 32, 519–572. http://dx.doi.org/10.1146/annurev.fluid.32.1.519 [Crossref]

  • [13] Kendall, J.M. (1985), Experimental study of disturbances produced in pretransitional laminar boundary layer by weak free stream turbulence, AIAA Paper 85, 1695.

  • [14] Macdonald, R.W. (2000), Modelling the mean velocity profile in the urban canopy layer, Bound.-Layer Meteor. 97, 25–45. http://dx.doi.org/10.1023/A:1002785830512 [Crossref]

  • [15] Manes, C., D. Pokrajac, O. Coceal, and I. McEwan (2008), On the significance of form-induced stress in rough wall turbulent boundary layers, Acta Geophys. 56, 3. http://dx.doi.org/10.2478/s11600-008-0021-2 [Crossref] [Web of Science]

  • [16] Martilli, A., A. Clappier, and M.W. Rotach (2002), An urban surface exchange parameterisation for mesoscale models, Bound.-Layer Meteor. 104, 261–304. http://dx.doi.org/10.1023/A:1016099921195 [Crossref]

  • [17] Nikora, V., D. Goring, I. McEwan, and G. Griffiths (2001), Spatially-averaged open-channel flow over a rough bed, J. Hydraul. Eng. ASCE 127, 2, 123–133. http://dx.doi.org/10.1061/(ASCE)0733-9429(2001)127:2(123) [Crossref]

  • [18] Poggi, D., G.G. Katul, and J.D. Albertson (2004), A note on the contribution of dispersive fluxes to momentum transfer within canopies, Bound.-Layer Meteor. 111, 615–621. http://dx.doi.org/10.1023/B:BOUN.0000016563.76874.47 [Crossref]

  • [19] Pokrajac, D., L.J. Campbell, V. Nikora, C. Manes, and I. McEwan (2007), Quadrant analysis of persistent spatial velocity perturbations over square-bar roughness, Experiments in Fluids 42, 413–423. http://dx.doi.org/10.1007/s00348-006-0248-0 [Web of Science] [Crossref]

  • [20] Raupach, M.R., and R.H. Shaw (1982), Averaging procedures for flow within vegetation canopies, Bound.-Layer Meteor. 22, 79–90. http://dx.doi.org/10.1007/BF00128057 [Crossref]

  • [21] Raupach, M.R., J.J. Finnigan, and Y. Brunet (1996), Coherent eddies and turbulence in vegetation canopies: the mixing layer analogy, Bound.-Layer Meteor. 78, 351–382. http://dx.doi.org/10.1007/BF00120941 [Crossref]

  • [22] Reynolds, R.T., P. Hayden, I.P. Castro, and A.G. Robins (2007), Spanwise variations in nominally two-dimensional rough-wall boundary layers, Experiments in Fluids 42, 311–320. http://dx.doi.org/10.1007/s00348-006-0243-5 [Crossref]

  • [23] Snyder, W.H., and I.P. Castro (2002), The critical Reynolds number for rough-wall boundary layers, J. Wind Eng. Ind. Aerodyn. 90, 41–54. http://dx.doi.org/10.1016/S0167-6105(01)00114-3 [Crossref]

  • [24] Yao, Y.F., T.G. Thomas, N.D. Sandham, and J.J.R. Williams (2001), Direct numerical simulation of turbulent flow over a rectangular trailing edge, Theoret. Comput. Fluid Dyn. 14, 337–358. http://dx.doi.org/10.1007/s001620050144 [Crossref]

About the article

Published Online: 2008-07-01

Published in Print: 2008-09-01



Citation Information: Acta Geophysica, ISSN (Online) 1895-7455, ISSN (Print) 1895-6572, DOI: https://doi.org/10.2478/s11600-008-0025-y. Export Citation

© 2008 Institute of Geophysics, Polish Academy of Sciences. This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License. (CC BY-NC-ND 3.0)

Citing Articles

Here you can find all Crossref-listed publications in which this article is cited. If you would like to receive automatic email messages as soon as this article is cited in other publications, simply activate the “Citation Alert” on the top of this page.

[1]
Sharon Moltchanov, Yardena Bohbot-Raviv, Tomer Duman, and Uri Shavit
Water Resources Research, 2015, Volume 51, Number 4, Page 2081
[2]
Costantino Manes, Dubravka Pokrajac, Omduth Coceal, and Ian McEwan
Acta Geophysica, 2008, Volume 56, Number 3
[3]
Sharon Moltchanov, Yardena Bohbot-Raviv, and Uri Shavit
Boundary-Layer Meteorology, 2011, Volume 139, Number 2, Page 333

Comments (0)

Please log in or register to comment.
Log in