Wind tunnel study on influences of morphological parameters on drag coefficient of horizontal non-uniform buildings

Abstract

The implementation of morphometric evaluations of complex buildings in urban areas is essential for urban canopy models. There are two main reasons for this: the impossibility of conducting a micrometeorological evaluation of a building that is still in the design phase and the difficulty of estimating the roughness height of an urban area containing complex buildings using an anemometric method. This study used wind tunnel experiments to investigate the effects of the planar area, frontal area, shape, and layout of buildings on their aerodynamic characteristics. The results indicated that the curves showing the relationships between the buildings drag coefficient, Cd, and the four morphological parameters had similar patterns, with Cd=b·exp(−xca)·xd. The influences on Cd of both the shape and layout parameters showed peaks, as did the planar and frontal densities. A surface roughness model based on the morphometric evaluations of the aerodynamic parameters of non-uniform buildings was developed.