Wind Tunnel Measurement of Turbulent and Advective Scalar Fluxes: A Case Study on Intersection Ventilation
| Autor: | Radka Kellnerova, Libor Kukačka, Štĕpán Nosek, Zbyněk Jaňour, Klára Jurčáková |
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| Rok vydání: | 2012 |
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Article Subject
Meteorology Flow (psychology) lcsh:Medicine Wind lcsh:Technology General Biochemistry Genetics and Molecular Biology Physics::Fluid Dynamics Intersection lcsh:Science General Environmental Science Wind tunnel Physics Air Pollutants lcsh:T Advection Turbulence lcsh:R Scalar (physics) General Medicine Mechanics Wind direction Ventilation Flow velocity lcsh:Q Environmental Monitoring Research Article |
| Zdroj: | The Scientific World Journal The Scientific World Journal, Vol 2012 (2012) |
| ISSN: | 1537-744X |
| Popis: | The objective of this study is to determine processes of pollution ventilation in the X-shaped street intersection in an idealized symmetric urban area for the changing approach flow direction. A unique experimental setup for simultaneous wind tunnel measurement of the flow velocity and the tracer gas concentration in a high temporal resolution is assembled. Advective horizontal and vertical scalar fluxes are computed from averaged measured velocity and concentration data within the street intersection. Vertical advective and turbulent scalar fluxes are computed from synchronized velocity and concentration signals measured in the plane above the intersection. All the results are obtained for five approach flow directions. The influence of the approach flow on the advective and turbulent fluxes is determined. The contribution of the advective and turbulent flux to the ventilation is discussed. Wind direction with the best dispersive conditions in the area is found. The quadrant analysis is applied to the synchronized signals of velocity and concentration fluctuation to determine events with the dominant contribution to the momentum flux and turbulent scalar flux. |
| Databáze: | OpenAIRE |
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