Numerical evaluation of wind pressures on flat roofs with the k- model

The results of an investigation regarding the numerical evaluation of wind pressures on flat roofs by using the Reynolds averaged Navier-Stokes equations and the standard k- turbulence model are presented. A low and a taller building model are considered and wind blowing from different directions is assumed. Data are presented for roof edges and corners. Experimental measurements are also carried out in a boundary layer wind tunnel and results are compared with the computed data. Over most of the roof surface area, the comparisons are good for normal wind conditions and the low building model. However, the present approach does not seem to yield adequate representations of available experimental data in the high vorticity region near the windward roof edges of the building, particularly for oblique wind conditions. The influence of proximity of grid points to the roof surface is examined in detail.