CFD simulations of wind distribution in an urban community with a full-scale geometrical model

Publication date: 15 May 2017
Source:Building and Environment, Volume 117
Author(s): Sumei Liu, Wuxuan Pan, Hao Zhang, Xionglei Cheng, Zhengwei Long, Qingyan Chen
A CFD study explored the use of wind information from a meteorological station to simulate wind distribution in an urban community, where the station may be located far away from the community. The study constructed a full-scale urban model with building details for the area from the meteorological station to the community. The full-scale model was typically 2 to 20 km long, which was between the micro-scale and the meso-scale model. The three-dimensional, steady Reynolds-averaged Navier-Stokes (RANS) equations was solved to simulate the urban wind flows. The investigation used two different roughness setting methods for the ground surface to approximate building structures. The two methods produced similar results, but only one of them was able to provide wind information close to the ground. The wind distribution computed by the full-scale model was compared with that computed by a micro-scale local model, where the computational domain included only building structures in the community and limited spaces in the vicinity of the community. The wind velocity computed by the full-scale model was 20% higher than the experimental data obtained by the local weather stations on a building rooftop in the community, and that computed by the micro-scale model was almost twice as much. The full-scale model is recommended for predicting wind distribution in an urban community, although more time is required for construction of the geometrical model.