Simulating the sheltering effects of windbreaks in urban outdoor open space

This paper presents a numerical and experimental study of wind environment in an urban open space containing windbreaks and buildings. The sheltering effects of windbreaks on outdoor open spaces has been investigated regarding their physical properties, such as porosity and locations. A selection of turbulence models and discretization schemes has also been evaluated in the CFD simulations in order to create a suitable module to simulate airflow in a domain containing both porous objects and bluff bodies. The result shows that the combination of the KE-two-layer model and SMART discretization scheme provides satisfactory accuracy to the modelling with affordable computing resources. It also shows that the effect of buildings on the flow regime behind windbreaks is significant, equivalent to the porosity of windbreaks when the outdoor space is comparatively small in proportion to the height of the windbreaks.