| Abstrakt: |
Dispersion models which are commonly used for the assessment of the performance of industrial facilities close to residential areas, such as CALPUFF and AERMOD, do not directly consider the flow of air around obstacles like vegetation, solid barriers (fences or noise walls) and buildings. As such, dispersion of pollutants emitted from those facilities may be modelled without the additional micro-scale mixing effects of these obstructions, potentially leading to the overstating or understating of predicted pollutant concentrations. The GRAL model has, in recent version releases, included the option to allow the consideration of vegetation along with the existing ability to consider both buildings and solid barriers. Given the complexity of suburban residential areas, the inclusion of barriers, buildings and vegetation can take a significant amount of time to ensure the data entered correctly represents the modelling domain. Whether this effort and time is justified needs to be considered when preparing a dispersion model. This paper examines the effects of vegetation, buildings and barriers on a residential area with emissions from a fictional industrial source situated close to the border of a residential area. Several scenarios were examined to investigate the individual and cumulative effects of adding different components to the model (progressively adding terrain, vegetation, barriers and buildings to a simple base model). Results of the modelling showed that there were significant differences observed between the modelled scenarios of the same source type when additional complexity was progressively added to the dispersion model. The paper outlines the concentration differences noted for the additional of terrain, vegetation, buildings and barriers. [ABSTRACT FROM AUTHOR] |
