The numerical prediction of pollution dispersion in urban environments by means of solution of the statistically steady
Reynolds Averaged Navier Stokes (RANS) equations is known to be strongly dependent on the turbulence models. In the case of
pollution dispersion turbulence models do not only have to be used for the Reynolds stresses but also for the turbulent scalar fluxes.
While the influence of several turbulence models for the Reynolds stresses on the dispersion in urban environments has been
examined already several times, the turbulent scalar fluxes were exclusively modelled by the simple gradient diffusion assumption.
In the present work therefore the influence of more advanced, anisotropic algebraic models for the turbulent scalar fluxes on the
dispersion in the MUST wind tunnel experiment is examined. To that end, three anisotropic algebraic flux models were
implemented in the commercial software FLUENT 6.3. All these models together with the simple gradient diffusion model (with
two turbulent Schmidt numbers) are performed and compared using statistical performance measures to assess their predictive
capability
