Prediction and study of passive pollutant dispersion in a street-canyon in London using computational fluid dynamics techniques

Pollution levels in an urban street-canyon area are determined numerically as part of the
European research project OSCAR using the ADREA-HF code. Aim of the modeling is
twofold: (i) to investigate the flow-field and carbon monoxide (CO) concentrations in the area
and (ii) compare with measurements. The latter is achieved due to the availability of
measurements, contrary to previous street-canyon-simulation studies where ADREA-HF was
used and where no measurements were available. Results show a tendency of overprediction
of CO concentration by the model that is attributed mostly to the uncertainty of the
meteorological data and emission levels within the studied time frames. The concentration
distribution and flow field within the canyon are shown to be highly correlated whereas the incanyon
induced vortex plays a prominent role in the concentration dispersion.