کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
293661 | 511161 | 2012 | 8 صفحه PDF | دانلود رایگان |
We investigate the effect of flow unsteadiness on the mean wind flow pattern in an idealized urban environment. To that extent, steady RANS and unsteady LES simulations of the flow around a city-block are conducted for various ambient wind directions. Our simulations reveal that the selected modeling approach can have a significant effect on (i) the mechanisms causing air exchange between the regions above and below roof level, (ii) the spatial distribution of the time-averaged exchange fluxes, and (iii) the total amount of air exchange. For some specific cases, the modeling approach even has a larger impact on the predicted air exchange rate than the ambient wind direction. These results are of key-importance to researchers and engineers involved in simulations of flow in the urban neighborhood.
► Detailed comparison between steady RANS and unsteady LES simulations.
► Analysis of flow around a city-block for various ambient wind directions.
► Different modeling approaches show to favor different exchange mechanisms.
► The modeling approach might have more impact on the results than the wind direction.
Journal: Journal of Wind Engineering and Industrial Aerodynamics - Volumes 104–106, May–July 2012, Pages 389–396