On the prediction of turbulent flows around full-scale buildings

Data from tests on a full-scale, single-span high eaves commercial glasshouse are used to quantify the uncertainties associated with the use of computational fluid dynamics to obtain wind load predictions for full-scale structures. It is demonstrated that the widely used assumption of two-dimensional flow field in the mid-span leads to serious overestimation of the suction pressures over the roof and on the leeward wall. It is further shown that the use of a Reynolds-stress closure enables the capture of flow reversal downstream of the windward eaves. In contrast, the industry-standard k}e model is found to predict no flow separation, contrary to the experimental observation. Finally, guidelines are suggested for suitable mesh distributions and for the e$cient sizing of the computational domain relative to the building’s dimen