Urban Atmospheric Flow Modeling Using a Lattice Boltzmann Model

As a part of the ABLE (Atmospheric Boundary Layer Environmental) modeling system, a Lattice Boltzmann Model (LBM) prototype was developed recently at the US Army Research Laboratory to simulate the complex turbulent flows in urban areas. The model can accommodate mechanical and thermal forcing due to buildings and the ground surface. The drag forces of tree canopies in urban can also be accounted for in the model.  As initial verification, we used the LBM to simulate turbulent boundary layer flows over a simplified urban area.  Examples of thermally driven flows are also used to demonstrate the capability of thermal energy coupling for convective and stably stratified flows. The flow in a forested area is also included in the simulation examples.