An evaluation of several turbulence schemes for the prediction of mean and turbulent fields in complex terrain

摘要: A prognostic three-dimensional mesoscale model has been developed andused in one- and two-dimensional modes to evaluate ten local turbulenceclosure schemes. The schemes ranged from first-order the two-equationprognostic Predictions by models were compared for aone-dimensional convective boundary layer using mixed scaling andmeasurements interpret results. Two-dimensional simulations alsoperformed a sea-breeze flow over hill. results showedthat all of considered, minor differences produced themean meteorological fields vertical scalar fluxes, but majordifferences apparent velocity variances dissipation rate.Predicted tracer concentrations very sensitive turbulence modelformulation dispersion point source boundarylayer, particularly prediction maximum concentrations. Predictedtracer surface volume two-dimensionalsimulations similar models, although degree mixing themorning growth period some differences. Generally, good forthe mean can be obtained with schemes, evenif they underpredict magnitude reasonable also thesemodels provided near-source effects are not important. performed best theconvective layer.