Experimental and numerical study of wind flow behind windbreaks

The shelter effect of a windbreak protects aggregate piles and provides a reduction of particle emissions in harbours. RANS (Reynolds-averaged Navier–Stokes equations) simulations using three variants of k–e (standard k–e, RNG k–e and realizable k–e) turbulence closure models have been performed to analyse wind flow characteristics behind an isolated fence located on a flat surface without roughness elements. The performance of the three turbulence models has been assessed by wind tunnel experiments. Cases of fences with different porosities (φ) have been evaluated using wind tunnel experiments as well as numerical simulations. The aim is to determine an optimum porosity for sheltering effect of an isolated windbreak. A value of 0.35 was found as the optimum value among the studied porosities (φ=0, 0.1, 0.24, 0.35, 0.4, 0.5).

[1]  Jong-Jin Baik,et al.  A Numerical Study of Thermal Effects on Flow and Pollutant Dispersion in Urban Street Canyons , 1999 .

[2]  A. J. Reynolds Flow Deflection by Gauze Screens , 1969 .

[3]  J. Santiago,et al.  Modelling the air flow in symmetric and asymmetric street canyons , 2005 .

[4]  P. Richards,et al.  Appropriate boundary conditions for computational wind engineering models using the k-ε turbulence model , 1993 .

[5]  Michael R. Raupach,et al.  A wind tunnel study of turbulent flow around single and multiple windbreaks, part I: Velocity fields , 1996 .

[6]  B. Launder,et al.  THE NUMERICAL COMPUTATION OF TURBULENT FLOW , 1974 .

[7]  S. Patankar Numerical Heat Transfer and Fluid Flow , 2018, Lecture Notes in Mechanical Engineering.

[8]  D. Olivari,et al.  Numerical and experimental modelling of pollutant dispersion in a street canyon , 2002 .

[9]  Domingos Xavier Viegas,et al.  Shelter effect on a row of coal piles to prevent wind erosion , 1988 .

[10]  B. Launder,et al.  The numerical computation of turbulent flows , 1990 .

[11]  John D. Wilson,et al.  Comments on ’a Numerical Simulation of Boundary-Layer Flows Near Shelterbelts‘ by H. Wang and E. Takle , 1997 .

[12]  S. Orszag,et al.  Renormalization group analysis of turbulence. I. Basic theory , 1986 .

[13]  William H. Rae,et al.  Low-Speed Wind Tunnel Testing , 1966 .

[14]  John D. Wilson,et al.  Numerical studies of flow through a windbreak , 1985 .

[15]  A. Chan,et al.  Strategic guidelines for street canyon geometry to achieve sustainable street air quality—part II: multiple canopies and canyons , 2003 .

[16]  Don W. Green,et al.  Perry's Chemical Engineers' Handbook , 2007 .

[17]  M. Perera,et al.  Shelter behind two-dimensional solid and porous fences , 1981 .

[18]  John D. Wilson,et al.  A Field Study of the Mean Pressure About a Windbreak , 1997 .

[19]  E. F. Bradley,et al.  Development of velocity and shear stress distribution in the wake of a porous shelter fence , 1983 .

[20]  K. J. McAneney,et al.  Multiple windbreaks: An aeolean ensemble , 1991 .

[21]  Maya Milliez,et al.  Numerical simulations of pollutant dispersion in an idealized urban area, for different meteorological conditions , 2007 .

[22]  John D. Wilson,et al.  Oblique, stratified winds about a shelter fence. Part II: Comparison of measurements with numerical models , 2004 .

[23]  A. R Packwood,et al.  Flow through porous fences in thick boundary layers: comparisons between laboratory and numerical experiments , 2000 .

[24]  Z. Su,et al.  Study of roughness lengths and drag coefficients over Nansha sea region, Gobi, desert, Oasis and Tibetan plateau , 2000 .

[25]  Hee-Chang Lim,et al.  A numerical study on flow around a triangular prism located behind a porous fence , 2001 .

[26]  John D. Wilson Oblique, Stratified Winds about a Shelter Fence. Part I: Measurements , 2004 .

[27]  Eugene Yee,et al.  Calculation of winds disturbed by an array of fences , 2003 .

[28]  W. Hung,et al.  Validation of a two-dimensional pollutant dispersion model in an isolated street canyon , 2002 .

[29]  Erich J. Plate,et al.  The aerodynamics of shelter belts , 1971 .

[30]  E. Takle,et al.  A numerical simulation of boundary-layer flows near shelterbelts , 1995 .

[31]  Weeratunge Malalasekera,et al.  An introduction to computational fluid dynamics - the finite volume method , 2007 .

[32]  B. Ruck,et al.  Double-Arranged Mound-Mounted Shelterbelts: Influence of Porosity on Wind Reduction between the Shelters , 2005 .

[33]  T. Shih,et al.  A new k-ϵ eddy viscosity model for high reynolds number turbulent flows , 1995 .

[34]  S. Orszag,et al.  Renormalization group analysis of turbulence. I. Basic theory , 1986, Physical review letters.

[35]  Sang Joon Lee,et al.  Verification of the shelter effect of a windbreak on coal piles in the POSCO open storage yards at the Kwang-Yang works , 2002 .

[36]  D. C. Stevenson,et al.  Wind protection by model fences in a simulated atmospheric boundary layer , 1977 .