Modeling Airflow in Urban Form against Sand Accumulation: a Case of Saltation in the Town of Timimoun in Southern Algeria

Document Type : Original Paper


1 Ph.D. Candidate, Laboratoire Architecture et environnement (LAE), Ecole Polytechnique d’Architecture et d’Urbanisme, EPAU, Alger-Algérie.

2 Professor, Ecole Polytechnique d’Architecture et d’Urbanisme, EPAU, Alger-Algérie.

3 Professor, Ecole Nationale d’Architecture de Toulouse, Toulouse, France.


In our present research, we focus on the modeling of airflow related to natural disasters, such as
sand accumulation, with urban form studies. The objective is to find which urban form can promote sand passing and
reduce as much as possible stagnation of sand in the building area (streets, alleys, etc.). The urban form design will be
discussed through the simulation of airflow by using Computational Fluid Dynamics (CFD). In terms of simulation,
we simulated the airflow behavior, which is responsible of sand stagnation in some specific configurations. A flat
ground was chosen with a first configuration, which was varied to test each time a current airflow behavior in this
configuration. This modeling is made possible following an appropriate turbulence model. In this study, a correlation
was made between urban wind speed and morphological parameters such as aspect ratio, building geometry and
building density. According to our theoretical references, this correlation shows that urban wind speed can help reduce
sand stagnation with proper values of these parameters. Therefore, through the urban form study we can promote wind
speed and blow away the accumulated sand till the urban limits.


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