Records |
Author |
Gorlé, C.; van Beeck, J.; Rambaud, P.; Van Tendeloo, G. |
Title |
CFD modelling of small particle dispersion: the influence of the turbulence kinetic energy in the atmospheric boundary layer |
Type |
A1 Journal article |
Year |
2009 |
Publication |
Atmospheric environment : an international journal |
Abbreviated Journal |
Atmos Environ |
Volume |
43 |
Issue |
3 |
Pages |
673-681 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
When considering the modelling of small particle dispersion in the lower part of the Atmospheric Boundary Layer (ABL) using Reynolds Averaged Navier Stokes simulations, the particle paths depend on the velocity profile and on the turbulence kinetic energy, from which the fluctuating velocity components are derived to predict turbulent dispersion. It is therefore important to correctly reproduce the ABL, both for the velocity profile and the turbulence kinetic energy profile. For RANS simulations with the standard kå model, Richards and Hoxey (1993. Appropriate boundary conditions for computational wind engineering models using the kå turbulence model. Journal of Wind Engineering and Industrial Aerodynamics 4647, 145153.) proposed a set of boundary conditions which result in horizontally homogeneous profiles. The drawback of this method is that it assumes a constant profile of turbulence kinetic energy, which is not always consistent with field or wind tunnel measurements. Therefore, a method was developed which allows the modelling of a horizontally homogeneous turbulence kinetic energy profile that is varying with height. By comparing simulations performed with the proposed method to simulations performed with the boundary conditions described by Richards and Hoxey (1993. Appropriate boundary conditions for computational wind engineering models using the kå turbulence model. Journal of Wind Engineering and Industrial Aerodynamics 4647, 145153.), the influence of the turbulence kinetic energy on the dispersion of small particles over flat terrain is quantified. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Oxford |
Editor |
|
Language |
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Wos |
000262737900023 |
Publication Date |
2008-10-16 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
1352-2310; |
ISBN |
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Additional Links ![sorted by Additional Links field, ascending order (up)](img/sort_asc.gif) |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.629 |
Times cited |
79 |
Open Access |
|
Notes |
Iwt |
Approved |
Most recent IF: 3.629; 2009 IF: 3.139 |
Call Number |
UA @ lucian @ c:irua:76016 |
Serial |
306 |
Permanent link to this record |
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Author |
Gorlé, C.; van Beeck, J.; Rambaud, P. |
Title |
Dispersion in the wake of a rectangular building : validation of two Reynolds-averaged Navier-Stokes modelling approaches |
Type |
A1 Journal article |
Year |
2010 |
Publication |
Boundary-layer meteorology |
Abbreviated Journal |
Bound-Lay Meteorol |
Volume |
137 |
Issue |
1 |
Pages |
115-133 |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
Abstract |
When modelling the turbulent dispersion of a passive tracer using Reynolds-averaged Navier-Stokes (RANS) simulations, two different approaches can be used. The first consists of solving a transport equation for a scalar, where the governing parameters are the mean velocity field and the turbulent diffusion coefficient, given by the ratio of the turbulent viscosity and the turbulent Schmidt number Sc (t) . The second approach uses a Lagrangian particle tracking algorithm, where the governing parameters are the mean velocity and the fluctuating velocity field, which is determined from the turbulence kinetic energy and the Lagrangian time T (L) . A comparison between the two approaches and wind-tunnel data for the dispersion in the wake of a rectangular building immersed in a neutral atmospheric boundary layer (ABL) is presented. Particular attention was paid to the influence of turbulence model parameters on the flow and concentration field. In addition, an approach to estimate Sc (t) and T (L) based on the calculated flow field is proposed. The results show that applying modified turbulence model constants to enable correct modelling of the ABL improves the prediction for the velocity and concentration fields when the modification is restricted to the region for which it was derived. The difference between simulated and measured concentrations is smaller than 25% or the uncertainty of the data on 76% of the points when solving the transport equation for a scalar with the proposed formulation for Sc (t) , and on 69% of the points when using the Lagrangian particle tracking with the proposed formulation for T (L) . |
Address |
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Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
Dordrecht |
Editor |
|
Language |
|
Wos |
000281712500006 |
Publication Date |
2010-06-30 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
|
Series Issue |
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Edition |
|
ISSN |
0006-8314;1573-1472; |
ISBN |
|
Additional Links ![sorted by Additional Links field, ascending order (up)](img/sort_asc.gif) |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.573 |
Times cited |
16 |
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.573; 2010 IF: 1.879 |
Call Number |
UA @ lucian @ c:irua:95570 |
Serial |
736 |
Permanent link to this record |