Development and Validation of a Fast CFD model for simulating flow and dispersion in urban areas and complex terrain

Aeolus is fast CFD model developed by the National Atmospheric Release Advisory Center (NARAC), which can efficiently simulate flow and dispersion in urban areas in minutes. This model can also be used for a larger region with complex terrain and accounts for atmospheric stability. The model can be run in an operational mode using Reynolds Averaged Navier Stokes model and in a more detailed and accurate mode using a Large Eddy Simulation model. The CFD model is accompanied by a fast Lagrangian dispersion model, which can predict the dispersion of buoyant, heavy and neutral gases. As a part of this presentation, Aeolus will be validated using Joint Urban 2003 field data, with the model results for wind field and tracer compared to available field data. The model will be run using both RANS and LES mode and the results will be discussed. Results from model validation for complex terrain and dispersion of heavy gas also will be presented.

This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. The Department of Homeland Security sponsored part of the production of this material.