Application of the k-ε model to flow over a building placed in different roughness sublayers

Predictions of three-dimensional airflows over a building-like model with complex boundaries by solving the Reynolds averaged Navier-Strokes equations are presented. The obstacle is placed in boundary layers characterized by different roughness, and which have a main stream velocity component at different angles to the object. The pressure distributions are compared to wind-tunnel measurements. The effect of turbulent characteristics of the oncoming flow on pressure distribution is shown out-lined through the simulation of various roughness sublayers. The different results suggest that only the base pressure distribution is seriously affected by turbulence intensity and surface roughness. These two parameters are found to be of major importance in reproducing accurately a natural boundary layer. Additionally, the calculations have shown that the flow field is very sensitive to the specification of inflow conditions for the rate of dissipation of turbulent kinetic energy. (C) 1998 Elsevier Science B.V. All rights reserved.