RESUMO
Pollutant emissions from aircraft operations contribute to the degradation of air quality in and around airports. Meeting the ICAO's environmental certification standards regarding both gaseous and particulate aircraft engine emissions is one of the main challenges for air-transportation development over the coming years. To increase the accuracy of airport air pollution monitoring and prediction, advanced decision-making tools need to be developed. In this context, the present study aimed at demonstrating the modeling capabilities of an innovative methodology that accounts for the microscale evolution of aircraft emissions, both spatially and temporally. For this purpose, 3D high-resolution CFD simulations were carried out in the CAEPport configuration (medium-size mock airport) as defined by the Committee on Aviation Environmental Protection (CAEP/8) for local air-quality assessment. The modeled domain extends up to 8 km around the airport. A spatial resolution down to 1 m was used around buildings to refine the prediction of pollutant-emission concentrations. The model accounts for ambient meteorological conditions along with the background chemical composition. NO x emissions from main engines and auxiliary power units (APUs) were individually tracked along LTO trajectories with a time resolution down to 1 s. The impact of atmospheric stability was investigated in three cases, i.e., stable, neutral, and unstable. The results show NO2 dominating in apron areas due to the low power setting of main engines along APU contribution during extended parking. Conversely, a domination of NO emissions was observed at the runway threshold due to the high power setting of the main engines. Stable atmospheric conditions promoted higher NO and NO2 concentrations as compared to both neutral and unstable cases. The use of APUs contributed to higher concentrations of both NO and NO2 emissions and especially of NO2 in terminal areas.
