Laura E. Venegas

Traffic pollution modelling in a complex urban street

This study explores for the first time, the applicability of the Danish Operational Street Pollution Model (OSPM) in the city of Buenos Aires where street canyons are very irregular. The model is applied in an irregular and asymmetric street canyon of a five-lane avenue near a street intersection. Urban background concentrations estimated by the DAUMOD model are considered. Meteorological information registered at the domestic airport located in the city is used in calculations. Three months of hourly NOx, NO2 and CO estimated concentrations are compared with measurements inside the street canyon. Statistical evaluation of model results shows that OSPM performance is quite good.

Study of natural and traffic-producing turbulences analysing full-scale data from four street canyons

Parameters related with natural and traffic producing turbulences are estimated for four street canyons considering all wind directions. Available data include air pollution concentrations measured in Gottinger Strasse (Hannover, Germany), Schildhornstrasse (Berlin, Germany), Jagtvej (Copenhagen, Denmark) and Hornsgatan (Stockholm, Sweden), background pollution, wind speed and direction measured on the roof of a nearby building and information of traffic flow. Results show that coefficients a and b, related to natural- and traffic- produced turbulences, vary with wind direction. The variation of critical wind speed with traffic density and wind direction is also studied for each street canyon.

Air pollution in a street canyon estimated considering different parameterisations of vehicle-induced turbulence

Leeward air pollutant concentrations (C) are estimated by incorporating four parameterisations of traffic-produced turbulence (TPT) into the scaling of C inside a street canyon. Three parameterisations consider expressions previously introduced by other authors, based on a theoretical formulation of TPT and a semi-empirical approach already incorporated in an operational street model. The fourth scheme introduces an empirical expression of TPT derived from four full-scale street canyon datasets. Hourly NO x concentrations are calculated for an asymmetric street canyon in Buenos Aires, using meteorological observations at local airport and modelled background concentrations. Statistical indicators show that the performance of the four schemes is satisfactory.