Scientists from Novosibirsk State Technical University (NSTU) conducted a numerical simulation assessment of the spread of pollutants generated by aircraft engines. The results can be used in calculating sanitary protection zones around airports.
Sanitary protection zones (SPZ) are established to protect residential buildings from negative chemical and physical effects. They create an environmental barrier, ensuring the safety of the public during the regular operation of the airport. SPZS are established, among other things, on the basis of calculations of the dispersion of pollutants generated during the operation of aircraft engines, taking into account background pollution. The boundaries are defined so that the maximum surface concentration of harmful substances on the outer boundary of the zone does not exceed 1 MPC.
According to Anna Turchinovich, Associate Professor of the Department of Environmental Engineering at NSTU-NETI, Candidate of Technical Sciences, the work on creating an approach for assessing the level of pollution from aircraft was carried out in two directions. A software product has been developed to calculate the dispersion of pollutants from moving sources. Using the program, you can calculate the level of pollution at different stages of the take-off and landing cycle.
"Each stage has its own characteristics. At the taxiing stage, the engines operate at low throttle, at the take—off stage - at maximum power, which leads to a change in the composition and amount of emissions. In addition, the ecological footprint of each airport is individual and depends on the intensity of flights, type of aircraft, infrastructure (geometry of taxiways, slope of runways) and geographical location, which affects the parameters of the atmosphere and, consequently, the nature of the dispersion of pollutants," explained Anna Turchinovich.
By uploading the airport territory to a program developed by NSTU NETI scientists, it is possible to plot the trajectory of the aircraft and calculate the emissions of pollutants by aircraft during the take—off and landing cycle, and using isolines to visualize their concentration level. The emission calculation method is based on a system of gas dynamic equations that describes the process of impurity propagation, taking into account diffusion and transport.
The second area of work of NSTU-NETI scientists within the framework of this project is to assess the level and nature of the spread of pollutants, taking into account their chemical activity and interaction with a deflecting device (gas collector). In aviation, there is such a thing as an "engine race" — a routine check of the performance of power plants in various modes performed on the ground. A mandatory element for the safe conduct of tests are gas collectors, which deflect and disperse a powerful stream of air.
"Using existing software systems, we simulated fuel combustion at maximum engine operation and low-thrust mode, taking into account the design of the gas collector (solid / cellular) and its location relative to the nozzle of the aircraft. Parametric calculations of the efficiency of the gas collector were performed with varying removal and the distance was determined, which significantly affects the dispersion of pollutants. The simulation results can be used in designing the location of the deflecting device," said Anna Turchinovich.
A software product created by university scientists to assess the level of pollution resulting from aircraft take-off and landing operations allows calculations for the design of sanitary protection zones of airports.