Abstract
The scalar concentration fluctuations within a plane parallel-to-the-ground surface were measured inside a model canopy composed of densely arrayed rods using the laser-induced fluorescence technique. Two-dimensional scalar concentration spectra were computed and were shown to exhibit an approximate −3 power-law scaling at wavenumbers larger than those associated with wake production during quiescent instances when von Karman vortex streets dominated the flow. However, during instances when sweeps disrupted the flow, the spectral exponents increased above −3. The −3 power-law for these concentration fluctuation spectra measurements was shown to be consistent with a simplified spectral budget for locally homogeneous and isotropic turbulence augmented with a relaxation time scale similarity argument that assumed a constant enstrophy injection rate and wake generation mechanism. Hence, the origin of this −3 power-law scaling here differs from the well-known −3 power-law result for the so-called inertial diffusive range derived for the scalar concentration spectrum at small Prandtl numbers.
Similar content being viewed by others
References
Batchelor G (1959) Small-scale variation of convected quantities like temperature in turbulent fluid. Part 1. General discussion and the case of small conductivity. J Fluid Mech 5: 113
Cava D, Katul G (2008) Spectral short circuiting and wake production within the canopy trunk space of an Alpine hardwood forest. Boundary-Layer Meteorol 126: 415
Corrsin S (1964) Further generalization of Onsager’s cascade model for turbulent spectra. Phys Fluids 7: 1156
Couder Y, Chomaz J, Rabaud M (1989) On the hydrodynamics of soap films. Physica D 37: 384
Danaila L, Antonia RA (2009) Spectrum of a passive scalar in moderate Reynolds number for homogeneous isotropic turbulence. Phys Fluids 21: 111702
Fey U, Konig M, Eckelmann H (1998) A new Strouhal Reynolds number relationship for the circular cylinder in the range 47 < R e < 23105. Phys Fluids 10: 1547
Finnigan J (2000) Turbulence in plant canopies. Annu Rev Fluid Mech 32: 519
Gibson C (1968) Fine structure of scalar fields mixed by turbulence. II. Spectral theory. Phys Fluids 11: 2316
Hill R (1978) Models of the scalar spectrum for turbulent advection. J Fluid Mech 88: 541
Hsieh C, Katul G (1997) The dissipation methods, Taylor’s hypothesis, and stability correction functions in the atmospheric surface layer. J Geophys Res Atmos 102: 16391
Katul G, Chang W (1999) Principal length scales in second-order closure models for canopy turbulence. J Appl Meteorol 38: 1631
Katul G, Chu C (1998) A theoretical and experimental investigation of the energy-containing scales in the dynamic sublayer of boundary-layer flows. Boundary-Layer Meteorol 86: 279
Katul G, Geron CD, Hsieh C, Vidakovic B, Guenther A (1998) Active turbulence and scalar transport near the land-atmosphere interface. J Appl Meteorol 37: 1533
Katul G, Mahrt L, Poggi D, Sanz C (2004) One and two equation models for canopy turbulence. Boundary-Layer Meteorol 113: 81
Kellay H, Goldburg W (2002) Two-dimensional turbulence: a review of some recent experiments. Rep Prog Phys 65: 845
Kolmogorov AN (1941) The local structure of turbulence in imcompressible viscous fluid for very large Reynolds number. Dokl Akad Nauk SSSR 30: 299
Kraichnan R (1967) Intertial ranges in 2-dimensional turbulence. Phys Fluids 10: 1417
Kraichnan R, Montgomery D (1980) Two-dimensional turbulence. Rep Prog Phys 43(5): 547
Laherrere J, Sornette D (1998) Stretched exponential distributions in nature and economy: fat tails with characteristic scales. Eur Phys J B 2: 525
Martin B, Wu X, Goldburg W, Rutgers M (1998) Spectra of decaying turbulence in a soap film. Phys Rev Lett 80: 3964
Nathan R, Katul G, Horn H, Thomas S, Oren R, Avissar R, Pacala S, Levin S (2002) Mechanisms of long-distance dispersal of seeds by wind. Nature 418: 409
Poggi D, Katul G (2006) Two-dimensional scalar spectra in the deeper layers of a dense and uniform model canopy. Boundary-Layer Meteorol 121(2): 267
Poggi D, Katul G (2007) An experimental investigation of the mean momentum budget inside dense canopies on narrow gentle hilly terrain. Agric For Meteorol 144: 1
Poggi D, Porporato A, Ridolfi L (2002) An experimental contribution to near-wall measurements by means of a special laser Doppler anemometry technique. Exp Fluids 32: 366
Poggi D, Katul G, Albertson J (2004a) Momentum transfer and turbulent kinetic energy budgets within a dense model canopy. Boundary-Layer Meteorol 111: 589
Poggi D, Porporato A, Ridolfi L, Katul G, Albertson J (2004b) The effect of vegetation density on canopy sublayer turbulence. Boundary-Layer Meteorol 111: 565
Poggi D, Katul G, Albertson J (2006) Scalar dispersion within a model canopy—measurements and three-dimensional Lagrangian models. Adv Water Resour 29: 326
Poggi D, Katul G, Cassiani M (2008) On the anomalous behavior of the Lagrangian structure function similarity constant inside dense canopies. Atmos Environ 42(18): 4212
Raupach M, Finnigan J, Brunet Y (1996) Coherent eddies and turbulence in vegetation canopies: the mixing-layer analogy. Boundary-Layer Meteorol 78: 351
Rusk J, Sesonske A (1966) Turbulent temperature fluctuations in mercury and ethylene glycol in pipe flow. Int J Heat Mass Transf 9: 216
Rutgers M (1998) Forced 2D turbulence: experimental evidence of simultaneous inverse energy and forward enstrophy cascades. Phys Rev Lett 81(11): 2244
Stutton M, Schjrring J, Wyers G (1995) Plant-atmosphere exchange of ammonia. Philos Trans Roy Soc Lond A 351: 261
Wells M, Clercx HJH, van Heijst G (2007) Vortices in oscillating spin-up. J Fluid Mech 573: 339
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Poggi, D., Katul, G.G. & Vidakovic, B. The Role of Wake Production on the Scaling Laws of Scalar Concentration Fluctuation Spectra Inside Dense Canopies. Boundary-Layer Meteorol 139, 83–95 (2011). https://doi.org/10.1007/s10546-010-9573-1
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10546-010-9573-1