Physical and CFD model used in the analysis of particles dispersion.

Air pollution, representing one of the major environmental crises affecting us all, is responsible for half a million deaths each year in Europe. This research shows a numerical model based on Computational Fluid Dynamics (CFD) and a methodology for its validation allowing to know the evolution of particles in open urban environments. In this case, the model represents an area of Gijón (Asturias), specifically chosen as it serves to highlight a location at which the daily limit values of PM10 set by the regulations are most frequently exceeded. A numerical model has been developed at a scale of 1:10,000 to simulate the dispersion of pollutants, including particulate emissions. A physical model at the same scale was built using 3D printing. This model was tested in a wind tunnel and analysed in the four main wind directions. To carry out the tests, a particle generation system was designed and manufactured, and the necessary infrastructure was built to take measurements using an optical particle meter. Results show that the numerical model meets the expected objectives and is capable of predicting the behaviour of particle dispersion in the air. The numerical model produces results in the same order of magnitude as the physical model, although there is a tendency to underestimate the maximum values with respect to the measured ones.

CFD model to study PM[Formula: see text] dispersion in large-scale open spaces.

Air pollution has become a major concern in industrial or highly populated areas. Although legislation has been enacted to limit pollution levels, air quality monitoring still needs to be carried out by stations which are located at fixed points unable to provide the spatial evolution of pollutants. This research, focused on the city of Gijón (Asturias), includes a Computational Fluid Dynamics model capable of simulating the dispersion of pollutants in a large urban environment (12x18 km[Formula: see text]). Different wind conditions were simulated with two sources of emission. The results show the influence of the terrain on the dispersion of pollutants in open spaces whilst simultaneously scrutinizing the origin of diffuse industrial pollution circulating over the city of Gijon. The simulation allows us to set limits in the areas with higher levels of contamination or to analyse the variations of particle concentration in height. Therefore, this research defines and validates a methodology to generate numerical models which grant us the opportunity to observe the spatial evolution of pollutants in large areas. This result endorses further use in other lines of research, such as the evaluation of corrective measures to improve air quality in highly polluted environments.