Open AccessImpact of vehicular emissions in an urban area of the Po valley by microscale simulation with the GRAL dispersion model
Author(s) -
Sara Fabbi,
S. Asaro,
Alessandro Bigi,
Sergio Teggi,
Grazia Ghermandi
Publication year - 2019
Publication title -
iop conference series. earth and environmental science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.179
H-Index - 26
eISSN - 1755-1307
pISSN - 1755-1315
DOI - 10.1088/1755-1315/296/1/012006
Subject(s) - microscale chemistry , environmental science , traffic flow (computer networking) , meteorology , air quality index , dispersion (optics) , traffic simulation , simulation , atmospheric sciences , intersection (aeronautics) , computer science , geography , engineering , transport engineering , physics , mathematics , mathematics education , computer security , optics
This work sets out the test of the GRAL model (Graz Lagrangian Model, vs.18.1) in the urban area of Modena (Po valley, Northern Italy). The simulation domain sizes 2 000 x 3 000 m 2 and it features ‘microscale’ cells of 4 x 4 m 2 . The simulation focuses on an intersection featured by large traffic flows next to a school and a regulatory air quality monitoring station classified as an urban traffic site. The model is a lagrangian particle dispersion model and it takes into account the presence of buildings as obstacles and generating microscale wind fields accordingly, making this class of model suitable for investigating spatial pattern of atmospheric pollution in urban areas where local accumulation might occur. The simulation investigates traffic emissions of nitrogen oxides (NO x ) over the period October 29 to November 10, 2016, when direct measurements of traffic flow were collected by four one-channel doppler radar traffic counters. These counters provided continuous estimate of vehicle length, speed and number. These latter data were combined with available traffic flows at rush hour by PTV VISUM mobility software and the fleet composition of the municipality to estimate the total NOx emissions by vehicular traffic over the roads included in the simulation domain. NO x simulated concentrations showed a moderate correlation with the NO x observations at the nearby monitoring site. To have a better insight on the potential and the limitations of the GRAL model, its results will be compared with the output of the lagrangian particle dispersion model PMSS over the same area.