Počet záznamů: 1  

Impact of roof height non-uniformity on pollutant transport between a street canyon and intersectionsle

  1. 1. 0476809 - UT-L 2018 RIV GB eng J - Článek v odborném periodiku
    Nosek, Štěpán - Kukačka, L. - Jurčáková, Klára - Kellnerová, Radka - Jaňour, Zbyněk
    Impact of roof height non-uniformity on pollutant transport between a street canyon and intersectionsle.
    Environmental Pollution. Roč. 227, August (2017), s. 125-138 ISSN 0269-7491
    Grant CEP: GA ČR GA15-18964S
    Institucionální podpora: RVO:61388998
    Klíčová slova: Urban array * 3D street canyon * pollution flux measurement * wind tunnel * coherent structures
    Kód oboru RIV: DG - Vědy o atmosféře, meteorologie
    Obor OECD: Meteorology and atmospheric sciences
    Impakt faktor: 4.358, rok: 2017

    This paper presents an extension of our previous wind-tunnel study (Nosek et al., 2016) in which we highlighted, the need for investigation of the removal mechanisms of traffic pollution from all openings of a 3D street canyon. The extension represents the pollution flux (turbulent and advective) measurements at the lateral openings of three different 3D street canyons for the winds perpendicular and oblique to the along-canyon axis. The pollution was simulated by emitting a passive gas (ethane) from a homogeneous ground-level line source positioned along the centreline of the investigated street canyons. The street canyons were formed by courtyard-type buildings of two different regular urban-array models. The first model has a uniform building roof height, while the second model has a non-uniform roof height along each building's wall. The mean flow and concentration fields at the canyons' lateral openings confirm the findings of other studies that the buildings' roof-height variability at the intersections plays an important role in the dispersion of the traffic pollutants within the canyons. For the perpendicular wind, the non-uniform roof-height canyon appreciably removes or entrains the pollutant through its lateral openings, contrary to the uniform canyon, where the pollutant was removed primarily through the top. The analysis of the turbulent mass transport revealed that the coherent flow structures of the lateral momentum transport correlate with the ventilation processes at the lateral openings of all studied canyons. These flow structures coincide at the same areas and hence simultaneously transport the pollutant in opposite directions.
    Trvalý link: http://hdl.handle.net/11104/0273575