Modelling the flow field for environmental applications
by
Silvana Di Sabatino
Dipartimento di Scienza dei Materiali, Universita' di Lecce, Lecce, IT
Coauthors: E. Solazzo(*), P. Paradisi (**) and R. E. Britter (*). (*) Engineering Department, University of Cambridge, Cambridge, UK; (**) ISAC-CNR, Lecce, IT.

Knowledge of the flow field is important for many environmental and engineering applications such as the modelling of pollutant dispersion in the atmosphere including the modelling of particle deposition on architectural artworks, for the modelling of odour from waste landfills and water reclamation works, for the determination of wind loads on buildings and bridges, etc.

In particular, flow over complex geometries such as urban areas are currently the subject of many studies because of the importance of the applications listed above in those areas. Spatial and temporal patterns of flow and dispersion in urban areas depend on many factors. These factors are: the type of terrain (e.g. hill, coast, desert), the prevailing meteorological conditions (e.g. strong/weak geostrophic winds) and the form of the buildings and their arrangement (e.g. isolated building/canyon; the high/low range of building heights etc). Research in the related disciplines of mesoscale meteorology, geography and urban planning have suggested that there are ranges of characteristic length scales, each with their own general features and each needing a different modelling approach. The modelling approach also depends on the requirements for accuracy and speed of computation.

This paper briefly reviews some techniques used to model the flow over complex geometry at the different spatial scales ranging from the city to the street scale. It then derives a model for the prediction of mean velocity profiles within and above urban areas at the neighbourhood scale which is intermediate between the city and the street scale. In this model, information about the building geometry is derived from morphological parameters available, for example, from Digital Elevations Models. Some applications of the model are also discussed.

Date received: September 12, 2004

Copyright © 2004 by the author(s). The author(s) of this document and the organizers of the conference have granted their consent to include this abstract in Atlas Conferences Inc. Document # caon-44.