Ensuring pedestrian safety and comfort are the prim requirements for any development. Development approval authorities, architect developers and wind engineers work together to achieve this requirement. Ground level wind conditions in areas adjacent to a proposed development are assessed using one of the three methods available to study pedestrian comfort. The methods are desktop, wind tunnel and computational fluid dynamics (CFD) Study. The choice of a particular method depends on the type of project.
Desktop study of pedestrian level wind is based on experience, literature review and building standards and codes. The desktop study is the initial assessment of the pedestrian level wind study. For some projects this assessment is sufficient for integrating into DA document. However, for complex building shapes or surroundings a wind tunnel study may be required.
Wind Tunnel Study
Wind tunnel study of pedestrian level wind uses Irwin sensors to measure the wind speed at pre-selected locations. The measurement locations will be determined in consultation with the design team. The assessment includes pedestrian safety and comfort for walking, standing or sitting according the intended use of the location.
Computational Fluid Dynamics (CFD) Study
Pedestrian level wind using CFD is usually carried out to determine the mean wind speed. The peak wind speed is determined based on an assumed gust factor. Comparison of the predicted wind speed with safety and comfort criteria will be based on mean as well as peak values.