E ect of "uctuating wind direction on cross natural ventilation in buildings from large eddy simulation

A large eddy simulation (LES) program with the Smagorinsky subgrid-scale model has been used to study cross natural ventilation in buildings, which has experimental data available from on-site measurements and a wind tunnel. Since natural wind changes direction over time, it is hard to reproduce this e ect in a conventional wind tunnel where the “wind” direction is 8xed. There are discrepancies between the on-site and wind-tunnel cases for the wind-pressure di erence across the buildings, the eddy size behind the buildings, and the wind speed distribution inside an apartment with cross ventilation. LES can successfully simulate both cases by changing or 8xing incoming wind direction, and the simulated results agree reasonably with the corresponding experimental data