On the prediction of turbulent flows around full-scale buildings

Data from tests on a full-scale, single-span high eaves commercial glasshou se are used to quantify the uncertainties associated with the use of comput ational fluid dynamics to obtain wind load predictions for full-scale struc tures. It is demonstrated that the widely used assumption of two-dimensiona l 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 d ownstream of the windward eaves. In contrast, the industry-standard k-epsil on model is found to predict no flow separation, contrary to the experiment al observation. Finally, guidelines are suggested for suitable mesh distrib utions and for the efficient sizing of the computational domain relative to the building's dimensions. (C) 2000 Elsevier Science Ltd. All rights reser ved.