ACP Atmospheric Chemistry and Physics ACP Atmos. Chem. Phys. 1680-7324 Copernicus Publications Göttingen, Germany 10.5194/acp-10-2475-2010 Linking urban aerosol fluxes in street canyons to larger scale emissions Tay B. K. 1 McFiggans G. B. 1 Jones D. P. 2 Gallagher M. W. 1 Martin C. 1 Watkins P. 2 Harrison R. M. 3 Centre for Atmospheric Science, SEAES, The University of Manchester, Manchester, M13 9PL, UK School of Mechanical, Aerospace and Civil Engineering, The University of Manchester, P.O. Box 88, Manchester M60 1QD, UK Division of Environmental Health & Risk Management, School of Geography, Earth & Environmental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK 11 03 2010 10 5 2475 2490 Copyright: © 2010 B. K. Tay et al. 2010 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://acp.copernicus.org/articles/10/2475/2010/acp-10-2475-2010.html The full text article is available as a PDF file from https://acp.copernicus.org/articles/10/2475/2010/acp-10-2475-2010.pdf

In this study we investigate ultrafine particle (UFP) fluxes using a first order eddy viscosity turbulence closure Computational Fluid Dynamics (CFD) model and determine the different factors that influence emissions of UFP into the urban boundary layer. Both vertical turbulent fluxes as well as the fluxes due to mean circulatory flow are shown to contribute to the overall ventilation characteristics of street canyons. We then derive a simple parameterised numerical prediction model for canyon top UFP venting which is then compared with tower based micrometeorological flux measurements obtained during the REPARTEE & CityFlux field experiments.

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