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Papers by Merah Aissa
Prácticas culturales juveniles y movimientos sociales en el mediterráneo: ¿Un cambio de época?, 2016, ISBN 978-84-608-5756-3, págs. 227-245, 2016
Communiquer. Revue de communication sociale et publique, 2016
Revue de communication sociale et publique 16 | 2016 Valorisation, stratégies et communication de... more Revue de communication sociale et publique 16 | 2016 Valorisation, stratégies et communication des territoires à l'épreuve de l'authenticité Valorisation, stratégies et communication des territoires à l'épreuve de l'authenticité
The nitrogen oxide gases are subject to fast chemical reactions. The time scales characterizing t... more The nitrogen oxide gases are subject to fast chemical reactions. The time scales characterizing these reactions are of the order of tens of seconds and thus, comparable with residence time of pollutants in street canyons. The objective of the present study is the performance of small-scale computations for an urban 3D by using a CFD (computational fluid dynamics) code (ANSYS-CFX) to provide steady state wind and pollutant concentration fields. A fast chemistry module simulating chemical reactions taking place within street canyons right after traffic pollutants are emitted is implemented to the model in order to assess the concentrations of NOx and ozone in space. Circulations created by the city itself and that affect pollutant dispersion are accounted for and hotspot concentrations that depend on street canyon scale effects are also computed. Reactive pollutant dispersion in the street canyon has been numerically investigated using CFD numerical simulation by means of k-e turbulen...
This study numerically investigates reactive pollutants (NO, NO2 and O3) flow and dispersion in a... more This study numerically investigates reactive pollutants (NO, NO2 and O3) flow and dispersion in a 3D street canyon in time and space, by using a CFD (computational fluid dynamics) code (ANSYS-CFX). An area source (sub-domains) for medium emissions of NOx was considered in the presence of background O3 concentration, with an ambient wind perpendicular to the along-canyon direction. Spatial and temporal variation of pollutants within the canyon was calculated to be significant. It was found that NO and NO2 concentrations were higher at the upwind buildings (at lower levels near the street bottom) than near the downwind buildings, the largest concentrations of O3 were observed towards the canyons’ windward wall as O3-rich air is brought into the canyon.
Prácticas culturales juveniles y movimientos sociales en el mediterráneo: ¿Un cambio de época?, 2016, ISBN 978-84-608-5756-3, págs. 227-245, 2016
Communiquer. Revue de communication sociale et publique, 2016
Revue de communication sociale et publique 16 | 2016 Valorisation, stratégies et communication de... more Revue de communication sociale et publique 16 | 2016 Valorisation, stratégies et communication des territoires à l'épreuve de l'authenticité Valorisation, stratégies et communication des territoires à l'épreuve de l'authenticité
The nitrogen oxide gases are subject to fast chemical reactions. The time scales characterizing t... more The nitrogen oxide gases are subject to fast chemical reactions. The time scales characterizing these reactions are of the order of tens of seconds and thus, comparable with residence time of pollutants in street canyons. The objective of the present study is the performance of small-scale computations for an urban 3D by using a CFD (computational fluid dynamics) code (ANSYS-CFX) to provide steady state wind and pollutant concentration fields. A fast chemistry module simulating chemical reactions taking place within street canyons right after traffic pollutants are emitted is implemented to the model in order to assess the concentrations of NOx and ozone in space. Circulations created by the city itself and that affect pollutant dispersion are accounted for and hotspot concentrations that depend on street canyon scale effects are also computed. Reactive pollutant dispersion in the street canyon has been numerically investigated using CFD numerical simulation by means of k-e turbulen...
This study numerically investigates reactive pollutants (NO, NO2 and O3) flow and dispersion in a... more This study numerically investigates reactive pollutants (NO, NO2 and O3) flow and dispersion in a 3D street canyon in time and space, by using a CFD (computational fluid dynamics) code (ANSYS-CFX). An area source (sub-domains) for medium emissions of NOx was considered in the presence of background O3 concentration, with an ambient wind perpendicular to the along-canyon direction. Spatial and temporal variation of pollutants within the canyon was calculated to be significant. It was found that NO and NO2 concentrations were higher at the upwind buildings (at lower levels near the street bottom) than near the downwind buildings, the largest concentrations of O3 were observed towards the canyons’ windward wall as O3-rich air is brought into the canyon.