Effect of urban geometry on pedestrian-level wind velocity

Abstract

The orientation of the streets and the height of continuous buildings cut off summer breezes and the prevailing wind in Izmir Turkey. Compared with the northern parts of Turkey the summer period in Izmir is relatively hot humid and long. Due to the dense urban structure and the expansion of hard surface materials the temperature in the city centre is higher than this centre's surroundings and this effect is called the urban heat island. Consequently pedestrian comfort in the city drops dramatically especially in locations where the wind flow is obstructed by buildings. In addition natural ventilation through the building facades is weakened due to the low average wind speed in the streets. For better outdoor and indoor comfort the citizens in Izmir should benefit from the prevailing wind and summer breezes locally named 'imbat' in the sea-land direction. Therefore the existing situation is examined through the field study in order to understand the natural ventilation potential at the pedestrian level in the selected main streets in Izmir.