Coherent structures in urban flow: E. Paterna
In the PhD of E. Paterna, relevant air flow features induced by air-building interaction, such as shear layers and wake regions are measured by time-resolved PIV. The analysis of the results shows the presence of coherent structure and organization of hairpin vortices in the turbulent boundary layer.
Measurement setup for flow around 9 cubes positioned in a regular array.
Instantaneous velocity field. Out of plane component of the velocity as measured by stereoscopic PIV showing three-dimensionality and organization of the flow.
Instantaneous velocity field. Hairpin vortices are accompanied by big bursts of air movements: sweeps (red) and ejections (blue).