A comparative study of two-equation turbulence models for simulating microscale wind flow

Numerical modelling of turbulence plays a crucial role in providing accurat e microscale wind fields which are necessary to predict transport and dispe rsion of pollutants in the vicinity of buildings reliably. Although more el aborate turbulence models have been developed, two-equation turbulence mode ls are widely applied in atmospheric flow and dispersion models. The large CPU time required for direct numerical simulation (DNS) and large eddy simu lation (LES) still prohibits their application to microscale wind flow simu lations of practical interest. In this study, the results obtained by the m icroscale model MIMO for the three-dimensional flow around a surface mounte d cubical obstacle, using different two-equation turbulence models, are dis cussed. The accuracy of the investigated turbulence models is assessed by c omparing the numerical results with wind tunnel measurements.