Abstract
A two-dimensional E-ε model, which included the effects of plant-atmosphere interaction, was used to simulate air flow downwind of forest edges for the purpose of predicting the microclimate in forest openings. A suitable set of wall functions was selected to consider the aerodynamic effects of the ground in the opening. The model with discretization and parameter schemes was validated using a set of data from a wind-tunnel experiment. The simulated wind speed and turbulence kinetic energy closely agreed with the measured values. After validation, the model was used to predict eddy diffusivity in the lee of the forest edge. The modelled spatial distribution of the eddy diffusivity agreed in general with that calculated using wind-tunnel measurements. The usefulness and limitations of the E-ε model are discussed.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Beljaars, A. C. M., Walmsley, J. L., and Taylor, P. A.: 1987, ‘A Mixed Spectral Finite-Difference Model for Neutrally Stratified Boundary-Layer Flow over Roughness Changes and Topography’, Boundary-Layer Meteorol. 38, 273–303.
Bradley, E. F. and Mulhearn, P. J.: 1983, ‘Development of Velocity and Shear Stress Distributions in the Wake of a Porous Shelter Fence’, J. Wind Eng. Ind. Aerodyn. 15, 145–156.
Chen, J. M., Black, T. A., Novak, M. D., and Adams, R. S.: 1995, ‘A Wind Tunnel Study of Turbulent Air Flow in Forest Clearcuts’, in M. P. Coutts and J. Grace (eds.), Wind and Trees, Chapter 4, Cambridge University Press, London.
Counihan, J.: 1969, ‘An Improved Method of Simulating an Atmospheric Boundary Layer in a Wind Tunnel’, Atmos. Envir. 3, 197–214.
Detering, H. W. and Etling, D.: 1985, ‘Application of the E-ε Turbulence Model to the Atmospheric Boundary Layer’, Boundary-Layer Meteorol., 33, 113–133.
Durst, F. and Rastogi, A. K.: 1980, ‘Turbulent Flow over Two-Dimensional Fences’, in Turbulent Shear Flows Vol. 2, selected papers from the 2nd International Symposium on Turbulent Shear Flows, London, 1979. Springer-Verlag, Berlin, pp. 218–232.
Durst, F., Launder, B. E., Schmidt, F. W., and Whitelaw, J. H.: 1979, Turbulent Shear Flows I, Springer Verlag, Berlin.
Finnigan, J. J. and Bradley, E. F.: 1983, ‘The Turbulent Kinetic Energy Budget Behind a Porous Barrier: An Analysis in Streamline Co-ordinates’, J. Wind Eng. Ind. Aerodyn. 15, 157–168.
Fritschen, L. J., Driver, C. H., Avery, C., Buffo, J., Edmonds, R., Kinerson, R., and Schiess, P.: 1969, ‘Dispersion of Air Tracers into and within a Forested Area’, Grant DA-AMC-28–04368-G8, U.S. Army Electronic Command, Atmosphere Sciences Laboratory, Ft. Huachuca, AZ.
Fritschen, L. J.: 1985, ‘Characterization of Boundary Conditions Affecting Forest Environment Phenomena’, in B. A. Hutchison and B. B. Hick (eds.), The Forest-Atmosphere Interaction, D. Reidel Publishing Company, Dordrecht, pp. 3–23.
Gash, J. H. C.: 1986, ‘Observation of Turbulence Downwind of a Forest-Heath Interface’, Boundary-Layer Meteorol., 36, 227–237.
Gosman, A. D. and Pun, W. M.: 1973, ‘Calculation of Recirculating Flows’, Mechanical Engineering Department Report, Imperial College, London.
Gosman, A. D., Launder, B. E., and Reece, G. J.: 1985, Computer-aided Engineering Heat Transfer and Fluid Flow, John Wiley and Sons, New York.
Green, S. R.: 1992, ‘Modelling Turbulent Air Flow in a Stand of Widely-Spaced Trees’, PHOENICS J. Comp. Fluid Dyn. and Applic. 5, 294–312.
Hagen, L. J., Skidmore, E. L., Miller, P. L. and Kipp, J. E.: 1981, ‘Simulation of Effect of Wind Barriers on Airflow’, Trans. ASAE 24, 1002–1008.
Hanjalic, K. and Launder, B. E.: 1972, ‘A Reynolds Stress Model of Turbulence and its Application to Asymmetric Shear Flows’, J. Fluid Mech. 52, 609–638.
Hinze, J. O.: 1959, Turbulence, McGraw Hill, New York.
Kitada, T.: 1987, ‘Turbulence Structure of Sea Breeze Front and its Implication in Air Pollution Transport — Application of k-ε Turbulence Model’, Boundary-Layer Meteorol. 41, 217–239.
Landsberg, J. J. and James, G. B.: 1971, ‘Wind Profiles in Plant Canopies: Studies on an Analytical Model’, J. Appl. Ecol. 8, 729–741.
Launder, B. E. and Spalding, D. B.: 1974, ‘The Numerical Computation of Turbulent Flows’, Comp. Methods Appl. Mech. Eng. 3, 269–289.
Li, Z., Lin, J. D. and Miller, D. R.: 1990, ‘Air Flow Over and Through a Forest Edge: A Steady-State Numerical Simulation’, Boundary-Layer Meteorol. 51, 179–197.
Lumley, J. L.: 1992, ‘Some Comments on Turbulence’, Physics of Fluds A 4(2), 203–211.
Mayhead, G. J.: 1973, ‘Some Drag Coefficients for British Forest Trees Derived from Wind Tunnel Studies’, Agric. Meteorol. 12, 123–130.
McNaughton, K. G.: 1989, ‘Micrometeorology of Shelter Belts and Forest Edges’, Phil. Trans. R. Soc. Lond. B. 324, 351–368.
Meroney, R. N.: 1968, ‘Characteristics of Wind and Turbulence in and Above Model Forests’, J. Appl. Meteorol. 7, 780–788.
Miller, D. R., Lin, J. D. and Lu, Z. N.: 1991, ‘Air Flow Across an Alpine Forest Clearing: A Model and Field Measurements’, Boundary-Layer Meteorol. 56, 209–225.
Ozem, H., Becker, H. A., Grandmaison, E. W., Pollard, A. and Sobesiak, A.: 1994, ‘Three Equation Models for Industrial Applications’, Proceeding of 2nd Annual Conference of the CFD Society of Canada, June 1–3, Toronto.
Patankar, S. V.: 1980, Numerical Heat Transfer and Fluid Flow, Hemisphere Publ. Washington, D.C.
Patankar, S. V. and Spalding, D. B.: 1972, ‘A Calculation Procedure for Heat, Mass and Momentum Transfer in Three-Dimensional Parabolic Flows’, Inter. J. Heat Mass Transfer 15, 1787–1806.
Raupach, M. R. and Shaw, R. H.: 1982, ‘Averaging Procedures for Flow Within Vegetation Canopies’, Boundary-Layer Meteorol. 22, 79–90.
Raupach, M. R., Coppin, P. A. and Legg, B. J.: 1986, ‘‘Experiment on Scalar Dispersion Within a Model Plant Canopy’, Part I: the Turbulence Structure’, Boundary-Layer Meteorol. 35, 21–52.
Raynor, G. S.: 1971, ‘Wind and Temperature Structure in a Coniferous Forest and a Contiguous Field’, Forest Science 17, 351–363.
Rodi, W.: 1980, ‘Turbuence Models for Environnental Problems’, in W. Kollmann (ed.). Prediction Methods for Turbulent Flows, Hemisphere Publication Company, London, pp. 259–349.
Rosten, H. I. and Worrell, J. K.: 1988, ‘Generalized Wall Functions for Turbulent Flow’, PHOENICS J. Comp. Fluid Dyn. and Appl. 8, 81–109.
Schilling, V. K.: 1991, ‘A Parameterization for Modelling the Meteorological Effects of Tall Forests — A Case Study of a Large Clearing’, Boundary-Layer Meteorol. 55, 283–304.
Seginer, I., Mulhearn, P. L., Bradley, E. F. and Finnigan, J. J.: 1976, ‘Turbulent flow in a Model Plant Canopy’, Boundary-Layer Meteorol. 10, 423–453.
Willmott, C. J.: 1981, ‘On the Validation of Models’, Phys. Geogr. 2, 181–194.
Wilson, J. D.: 1985, ‘Numerical Studies of Flow through a Windbreak’, J. Wind Eng. Ind. Aerodyn. 21, 119–154.
Wilson, J. D.: 1988, ‘A Second-Order Closure Model for Flow through Vegetation’, Boundary-Layer Meteorol. 42, 371–392.
Author information
Authors and Affiliations
Additional information
Presently with Intera Information Technologies Corporation, IMS Division, 2 Gurdwara Road, Nepean, Ontario, Canada K2E 1A2.
Corresponding author, and presently with Canada Centre for Remote Sensing, 419-588 Booth Street, Ottawa, Ontario, Canada K1A 0Y7.
Rights and permissions
About this article
Cite this article
Liu, J., Chen, J.M., Black, T.A. et al. E-ε modelling of turbulent air flow downwind of a model forest edge. Boundary-Layer Meteorol 77, 21–44 (1996). https://doi.org/10.1007/BF00121857
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00121857