IMPLEMENTATION OF NEWLY DEVELOPED ALGORITHMS IN THE SIMULATION OF ATMOSPHERIC TURBULENT TRANSPORTS

The paper presents a three-dimensional transient numerical model for a tmospheric wind flow and industry and/or traffic pollutant dispersion over terrains having a complex topography. The model is based on a fin ite-volume integration of the equations governing mass, momentum, heat and pollutant transport within the earth's atmospheric boundary layer , using a collocated grid arrangement. The instability provoked by suc h a formulation was avoided by using a special pressure-velocity coupl ing. Local refinement of the grid was achieved via a domain decomposit ion method. The technique of 'porosity' used to approximate curved thr ee-dimensional boundaries is incorporated in the procedure, thus avoid ing the less accurate and more common approximation by a broken surfac e with segments parallel to the coordinate lines. The method was valid ated by simulating the how over the Attica peninsula for which measure ments of wind speed and pollutant emissions are available. (C) 1997 El sevier Science Ltd.