Computational fluid dynamics study on wind, solar effect and pollutant dispersion in Masdar City

Advanced architectural designs of street canyons facilitate the improvement of thermal comfort in urban cities. A clear demonstration is found in Masdar City Abu Dhabi, a growing sustainable city powered by renewable energy. While thermal comfort is important, air quality should also be maintained. This work investigates pollution dispersion patterns and effects of solar radiation in Masdar City. A two-dimensional model of the city cross-section is used for simulations while adopting the k-ε model in ANSYS FLUENT. The effect of solar radiation is examined at three times of the day: morning, noon, and evening. For wind, both constant and uniform wind profiles are considered. The main pollutants considered in this study are carbon dioxide and water vapour (humid air) in the form of transport species. Results show that the canyon maintains thermal comfort in the morning and evening; at noon however, temperature rises in the canyon to about 35°C. For pollutants coming from an external source, the bottom of the canyon has less concentration of pollutants. Conversely, in the case of pollutants emanating from within the canyon (Masdar City), the concentration of pollutants is high hence indicating that they do not easily escape. Overall, while the structure in Masdar City ensures thermal comfort, it might be difficult for pollutants and humid air to escape.