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

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61388998%3A_____%2F17%3A00476809" target="_blank" >RIV/61388998:_____/17:00476809 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.1016/j.envpol.2017.03.073" target="_blank" >http://dx.doi.org/10.1016/j.envpol.2017.03.073</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.envpol.2017.03.073" target="_blank" >10.1016/j.envpol.2017.03.073</a>

Jazyk výsledku

angličtina

Název v původním jazyce

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

Popis výsledku v původním jazyce

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.

Název v anglickém jazyce

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

Popis výsledku anglicky

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.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10509 - Meteorology and atmospheric sciences

Projekt

<a href="/cs/project/GA15-18964S" target="_blank" >GA15-18964S: Experimentální výzkum organizovaných struktur v turbulentní mezní vrstvě s vnější turbulencí</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2017

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Environmental Pollution

ISSN

0269-7491

e-ISSN

—

Svazek periodika

227

Číslo periodika v rámci svazku

August

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

14

Strana od-do

125-138

Kód UT WoS článku

000403991600015

EID výsledku v databázi Scopus

2-s2.0-85018292201