Real-time prediction of urban flow and dispersion

We propose a CFD algorithm for real-time prediction of urban flow and dispersion based on large-eddy simulation (LES). To efficiently handle complex urban building geometry, we implement a modified immersed boundary method (IBM), which can be applied to bluff building boundary on a staggered grid. For an introduction of proper inflow condition, we apply a synthetic-eddy method to the periodic domain, which is necessary for direct solving of Poisson equation for pressure. All these implementations are conducted on GPU system for a significant reduction of calculation time for real-time prediction. For validation of our algorithm, we test our model in the prediction of flow and dispersion in urban area in Seoul against wind-tunnel experiment result and other simulation using fire dynamics simulator (FDS). Our model simulation results of flow and dispersion show good agreement with them. Simulation time is reasonably short to warrant real-time prediction of flow and dispersion.