Effect of morphology and an upstream tall building on a street canyon flow
Abstract
The effects of the morphological model and the existence of an upstream tall building on the turbulent street canyon flow and the overlying boundary layer are investigated in a wind tunnel, using Stereoscopic Particle Image Velocimetry (S-PIV) measurements. The velocity variances, Reynolds shear stress, and turbulent kinetic energy are found to be larger than in a similar idealized street canyon model. Increasing building height results in a decrease in vertical mass fluxes across the opening of the canyon, at least in the canyon portion directly downstream of the building. The interaction between the large-scale structures in the overlying boundary layer and the small-scale structures in the street canyon is also investigated. The morphology does not impact the amplitude modulation mechanism of scale interaction, while an upstream building with a significantly larger height than the surroundings can greatly alter the scale interaction.