Generating a wind environment for large eddy simulation of bluff body flows

Large eddy simulations (LES) of turbulent flow past a bluff body placed in a wind environment requires that time-dependent inflow boundary data be generated to describe the surrounding wind environment. The important wind parameters are the Jensen number (or roughness ratio), the turbulence intensity, the turbulence integral length scale ratio, and the Reynolds number: an LES model with parameters appropriate for a full-scale urban wind environment with a roughness scale of 0.3-0.8 m and able to accommodate a building of 10-20 m height is described in detail, including computed mean velocity profile, turbulent intensity profiles, auto-correlation functions and the turbulence integral scale, and the turbulence spectra. The Reynolds number is sufficiently large for the flow past the building to be effectively Reynolds number independent. (C) 1999 Elsevier Science Ltd. All rights reserved.