This paper presents the basic principles of the method of calculating air pollution from road traffic in an urban built-up area. The algorithm of the method is based on the numerical integration of stationary two-dimensional partial differential equations of turbulent diffusion, with boundary conditions for the street canyons. The method consists of two modules: KALIB and STREETS, which calculate ...
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 ...
The municipality of Utrecht has ten years of experience with exceeding the pollution limit values for NO2 and benzene, and offering advice for traffic plans on the effects of air pollution. Utrecht promotes prevention and integration of environmental issues in traffic plans and town planning. Utrecht has widened the use of the Dutch air pollution model for traffic (CAR) to prevent new exceeding ...
As part of an overall measurement programme to monitor road traffic noise in Århus (Denmarks second largest city), the Local Authority set up a noise measurement station on one of the major approach roads to Århus Harbour. This noise measurement station continually measures noise levels and can give a round-the-clock picture of noise level variations. Like most other districts, Århus Local ...
The new version of the Atmospheric Dispersion Modelling System for urban environments, ADMS-Urban, is based on the same up-to-date physics as the ADMS model, outlined briefly here in Section 2. The basic model has been the subject of extensive validation studies: as part of this series of European Harmonisation Workshops; sponsored by HMIP (Her Majesty's Inspectorate of Pollution, now part of the ...
A numerical simulation of the traffic pollutant transport diffusion within one busy street of Nantes city centre has been realised for a real-time duration of 24 hours, with a time step of 20 ms, in low wind, sunny conditions. It has been generated with the urban canopy model CHENSI, which includes sub-models of thermal buoyancy, traffic emission rates, car induced turbulence. A number of frames ...
Traffic management systems are commonly used to optimize traffic flow in urban areas, e.g. to prevent traffic congestion. However, the regulation of traffic flows can also be used to control traffic induced emissions and therefore affects air quality. To use a traffic management system as an instrument for the benefit of air quality, the application requires reliable information about the current ...
The Traffic Air Quality (TAQ) model is a simple tool to estimate traffic fine particulate emissions on roadways (g/km) and can be used for both real-time analysis and for localized conformity analysis (“hot-spot” analysis for nonattainment areas) as defined by 40 CFR 93.123. This paper is a follow-up to a study published earlier regarding the development of the TAQ model. This paper shows how ...
An integrated methodology was applied, within the framework of the ALPNAP Project, to study the meteorology and traffic pollutant dispersion in highly complex topography, the Frejus Alpine transect area. Three episodes, characterised by strongly critical dispersive conditions, were considered in the year 2004. The atmospheric circulation and pollutant dispersion were simulated using RMS ...
From 1991 to 1999, there were significant commitments to environmental protection in Argentina. During this period, several important cities of the country, such as Buenos Aires, Cordoba, Mendoza, Bahia Blanca, and Ushuaia, began air quality monitoring programmes. Among these cities, we have taken Cordoba as a case study because of the existence of a continuous monitoring campaign that collected ...
This paper presents an air quality study in an urban traffic hot-spot in Lisbon, Portugal, by comparing the atmospheric pollutant concentrations obtained by a numerical model with measured values. Results indicate that the mean variation of particle and gaseous concentrations followed the traffic flow rate, evidencing the occurrence of PM10 concentrations greater than the respective air quality ...
Vehicles' 'wakes' are generated as a result of vehicular movements. They are one of the dominant factors in dispersing the pollutants in 'calm' meteorological conditions when wind velocity is ...
In this paper authors compare two different approaches of 10 μm particles (PM10) dispersion modelling in urban areas. The study is focused on comparison of the Eulerian-Lagrangian approach accurately describing particle aerodynamics and the passive scalar approach representing simplified alternative for description of dispersion processes. CFD code StarCD has been used for this study as ...
This paper presents the application of the Integrated Transport Effect Modelling System (ITEMS) in the city of Kaunas, Lithuania, taking into consideration some factors such as existing vehicle fleet, traffic flows, and ambient air quality monitoring data. The objective of this study is to estimate the exhausts of CO, NOx, and SO2 released by motor vehicles in relation to predictive traffic ...
This paper evaluates the exposure of four children to carbon monoxide (CO) in two different classrooms during the time spent in school in a typical school day, using a numerical modelling approach. The study is focused on an area of 550 × 550 m 2 centred at a primary school of the city of Aveiro, in central Portugal, which is located close to a road with moderate traffic and has naturally ...
This paper introduces utilisation of the CFD technique for modelling of PM10 (particulate matter 10 µm) dispersion in urban areas, with focus on detailed description of processes in the ground surface boundary layer. The description of deposition and re–suspension processes is introduced and applied on the city–scale model of the city of Brno (pop. 400,000). The air threshold ...
In the EU 5th framework project DECADE (2001–2003), a new methodology has been developed to calculate in detail the engine power required to drive a given vehicle over any particular route. It includes the rapidly changing (transient) demands placed on the engine, an area that has proved an obstacle to accurate simulations in the past. Together with the associated speed profiles, the actual power ...
This paper presents results from a numerical study which was conducted in order to investigate the effect of the flow around moving vehicles on the dispersion and the concentration of traffic emitted pollution within the Traforo Umberto road tunnel in the city centre of Rome. A series of three dimensional numerical transient simulations were performed using the commercial CFD code Ansys CFX 5.7.1 ...
The CALINE series of models was developed to estimate pollutant concentrations from motor vehicles at roadway intersections. It includes three primary models: CALINE, CAL3QHC, and CAL3QHCR. The latter allows processing of real meteorological data (up to one year) and input of vehicular emissions, traffic volume, and signalization (ETS) data. Data reflecting traffic conditions for individual hours ...
A 3-D Eulerian-Lagrangian approach to moving vehicles is presented that takes into account the traffic-induced flow rate and turbulence. The method is applied to pollutant dispersion in an individual street canyon and a system of two street canyons forming a perpendicular intersection. The approach is based on computational fluid dynamics (CFD) calculations using a Eulerian approach for ...