A comparison of airflow patterns from the QUIC model and an atmospheric wind tunnel for a two-dimensional building array and a multi-city block region near the World Trade Center site

QUIC, a fast running mass consistent diagnostic wind field model coupled with a Lagrangian particle based dispersion model with a semi-empirical foundation, has shown promise in aiding our understanding of local urban flow and dispersion. This paper describes a comparison of velocity measurements between the QUIC model and the laboratory wind tunnel for two cases: a simplified cubical building array and an extremely complex group of buildings surrounding the World Trade Center (WTC) site in lower Manhattan. A several block area, including the Woolworth building, was modeled to the east of the WTC site. The flow in the wind tunnel model of lower Manhattan was complex, with significant areas of backflow and blockage around regions of the city. Flow patterns appeared to strongly depend on local geometry with notable regions of channeling down streets and recirculation within street canyons. Most of these flow features were adequately captured by the QUIC model.