DISCUSSION ON GRID SIZE AND COMPUTATION DOMAIN IN CFD SIMULATION OF PEDESTRIAN WIND ENVIRONMENT AROUND BUILDINGS

With the rapid development of computers and CFD, pedestrian level wind study using CFD has become important in engineering design in recent years. In the United Kingdom, wind study is now a common engineering practice and a mandatory documentation for plan authority. The paper presents preliminary CFD simulation of pedestrian wind environment around buildings of typical configuration, size and orientation. The results were compared for flow pattern and the wind velocity amplification value at the pedestrian level, a horizontal surface 1.5 m above ground. The grid size and computation domain independent results were obtained when the grid size in the pedestrian level is less than 1.0 m and the computation domain dimensions are greater than five times the height of buildings under the conditions