Large eddy simulation of city micro-atmospheric environment
Tóm tắt
Air quality is one of the important conditions for a better residence life in the populated urban area and it is closed related to the micro-atmospheric environment. Atmospheric environment is controlled by air motion with multi-scales in the city, while air flows in the residence area are of micro-scale atmospheric motion. This paper introduces a modern numerical simulation method, i.e. large eddy simulation (LES), for studying micro-atmospheric flows in the city residence area. For the complex flow features in the residence area, the proper application of LES is studied and various numerical methods are compared in order to investigate their effects on the prediction accuracy of micro-atmospheric flows, for instance, roughness elements and immersed boundary method for complex terrain, different subgrid models and so on. The wind field (including turbulence properties) and contaminant dispersion are computed by the proposed method for a model and a realistic residence area, and the numerical results are in good agreement with the experimental measurements.
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