Field experiments of flow and dispersion within a street canyon in outdoor urban scale model
Field experiments of air flow and pollution dispersion within a street canyon in the Comprehensive Outdoor Scale Model (COSMO) facility were conducted to investigate the effect of the mean and turbulent flow above the canyon on pollutant dispersion inside the canyon. Tracer gas concentration was measured using fast–response photo ionisation detectors. Three–dimensional wind velocity components were also simultaneously measured using ultrasonic anemometers within and above the same canyon. Using both tracer gas concentration and velocity fluctuation data, we investigated the effects of atmospheric turbulence above the height of the buildings on pollution dispersion within the street canyon.
Keywords: street canyons, cavity eddy, pollutant dispersion, atmospheric turbulence, outdoor urban scale models, dispersion modelling, air quality, air pollution