Numerical analysis of surface pressure coefficients for a building with balconies

Knowledge of the pressure distribution on building walls is essential to evaluate wind-induced natural ventilation and to assess wind loads on building walls and building components. Computational Fluid Dynamics (CFD) can be a valuable tool for determining mean wind pressure coefficients on building facades. However, while many CFD studies of mean wind pressure on buildings have been performed in the past, the vast majority of these studies focused on simple building geometries without facade details. This paper presents a systematic evaluation of 3D steady RANS CFD for predicting mean wind pressure distributions on windward and leeward surfaces of a medium-rise building with and without balconies. The evaluation is based on a grid-sensitivity analysis and on validation with windtunnel measurements. The impact of several computational parameters is also investigated, including the resolution of the computational grid, the turbulence model and building balconies. The results show that steady RANS can accurately reproduce the mean wind pressure distribution across the windward facade. 3D steady RANS CFD has also been shown to provide accurate predictions of the mean wind pressure at the leeward wall in case of a perpendicular approach flow wind direction. This however is not the case for oblique flow.