Effect of urban morphology on wind flow distribution in dense urban areas

Environmental flow modelling can be achieved either by using wind-tunnel studies or via the utilization of Computational Fluid Dynamics (CFD) techniques. Conducting wind-tunnel studies may be expensive and time consuming, particularly in the event of additional test requirements with modified building and/or environmental configurations. On the other hand, CFD can provide significant cost benefits for assessing and optimizing engineering design solutions related to environmental concerns and appear attractive as a potential alternative tool. By using CFD in this manner it is anticipated that these types of advanced performance-based studies will be a useful tool and essential aid for urban designers and environmental planners. This paper discusses ongoing development and application of CFD simulations through a case study using CFD software for simulating air flow around a specific vernacular urban fabric of Ghardaïa. The potential of CFD for prediction of wind speeds around a complicated urban environment and a complex fabric structures is investigated. As the 3D solid model of the geometry was not available a captured Google Earth image of the fabric structure was used as a backdrop in the AC3D software, supplied as a utility to Phoenics. The outlines of the buildings were then traced to create polygons, which were then extruded to produce the individual buildings. Finally, the entire scene was exported to the VR-Editor as a single Phoenics object