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Even with all the benefits an airports brings, it may produce significant impacts on those living nearby and on the environment. Lately, interest in this problem has intensified in connection with increasing air traffic (at a mean annual rate of 5-7%) and a growing public awareness of local air quality around the airports. An aircraft is an importa...
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Context 1
... [39] also explained the revealed mechanisms and behavior of the wall jet as consequence of restricted surface impact on flow characteristics. shows that buoyancy effect parameters of exhaust gases decrease twice for wall jet (Table 2). And, the difference between the appropriate longitudinal coordinate of the buoyancy effect is nearly 30%. ...
Citations
... According to the mathematical equations used, there are many variations in the pollutant dispersion model. One of them is the Gaussian Plume model, which is most often used for various types of emission sources [5]. One of the software's applying the Gaussian plume model is AERMOD. ...
Pollutant dispersion modeling in around Yogyakarta International Airport wasconducted using AERMOD software. There is a strong positive correlation between the number of aircraft and land transportation and the number of pollutants considered. The ambient air quality at the study site for all pollutants originating from the landing and take-off (LTO) cycle is still below quality standards, but for those sourced from the combination of the LTO cycle and land transport traffic for NO2 pollutants exceed the quality standard, while for CO and hydrocarbon pollutants it is still below quality standards.
... Presently computational fluid dynamics (CFD) codes are widely used for assessments of the near-field (street-or micro-scale) atmospheric dispersion of pollutants in different air pollution studies [1][2][3][4]. When applied in urban air pollution studies such models are capable to account for the influence on atmospheric transport of the circulations created by interactions of buildings and other obstacles with airflow. ...
The OpenFoam CFD code was adapted to simulate atmospheric transport of pollutants. By performing calculations on unstructured grids and using the modifications of turbulence parameterizations to account for the influence of Earth’s rotation on PBL structure, the presented model can take into account the influence of urban obstructions and complex topography on atmospheric dispersion from a city to street-scale. The normalized mean squared error of simulated results for the conditions of the known MUST experiment was comparable with the results of other models (NMSE≈0.6). The value of turbulent Schmidt number in this experiment was estimated to be Sc≈0.4. The example of model application for the assessment of atmospheric pollution created by the industrial site of uranium production was presented.
... The analysis of emission inventories from major European and Ukrainian airports has highlighted, that aircraft are the dominant source of air pollution in most cases considered. Aircraft is a special source of air pollution due to some features [16]. ...
... Currently models (PolEmiCa [16,17], EDMS [18], LASPORT [19]) for airport air quality are based on the semi-empirical approaches for description of fluid dynamic of exhaust gases jet from aircraft engine and do not take into account an influence of the ground on jet behaviour and the interaction between the jet and the wing trailing vortex system. Eliminating the fluid mechanisms of aircraft wake vortex in considered modelling systems may overestimate the height of buoyancy exhaust gases jet from aircraft engine, underestimate its length and radius of expansion, dispersion characteristics and contaminants concentration values. ...
Purpose: Currently models for airport air quality are based on the semi-empirical approaches for description of fluid dynamic of exhaust gases jet from aircraft engine and do not take into account an influence of the ground on jet behaviour and the interaction between the jet and the wing trailing vortex system. Eliminating the fluid mechanisms of aircraft wake vortex in models of airport air quality may overestimate the height of buoyancy exhaust gases jet from aircraft engine, underestimate its length and radius of expansion, dispersion characteristics and contaminants concentration values. Evaluation the entrainment and mixing processes of the engine emissions in the plume by using CFD-code is an actual task for airport air quality studies. Methods: Numerical investigation of properties and structure of aircraft engine jets with CFD codes (OpenFOAM) will give a realistic checked material, on the base of which a necessary scientific reasoning of transportation of the contaminants by engine jets. Results: Comparison between OpenFOAM numerical results and semi-empirical jet model calculations (used by complex model PolEmiCa) show that buoyancy effect parameters of exhaust gases decrease twice for wall jet. And the difference between appropriate longitudinal coordinate of buoyancy effect is near to 30%. Discussion: using CFD tool allows to improve an airport air quality analysis by providing more objective and accurate input data for further dispersion modelling.
... Considered version of complex model PolEmiCa is based on a semiempirical model of turbulent jets and not taking into account ground surface impact on jet structure and its behavior [11]. It was argued that development of threedimensional model of exhaust gases jet from aircraft engine near the ground is an important research topic for airport LAQ [24][25][26]. ...
... The zone of ground vortices formation-between ground surface and aircraft engine exhaust nozzle-is characterized by structured mesh with higher resolution, with an aim to investigate the ground vortices generation processes and basic mechanisms of boundary layer formation, ground surface impact on fluid flow mechanics, and particularly Coanda effect occurrence. Zone of engine nozzle exhaust is discretized using a very fine structured mesh to capture the jet development pattern and its vortices structure [24,25]. ...
... LES provides an approach inside which large eddies are explicitly resolved in time-dependent simulation using low-pass-filtered Navier-Stokes equations [25]. Smagorinsky's subgrid model was set to model the smaller eddies (fluctuation component of instantaneous velocity of modeling fluid flow) that are not resolved in the LES. ...
... The complex model PolEmiCa has been sufficiently improved with respect to the jet transport model by using a CFD package (Fluent 6.3) to investigate the physics and characteristics of ground vortices, which are generated between the ground surface and the aircraft engine nozzle, in order to assess the ground surface impact on the jet flux structure, parameters and basic mechanisms of the jet development. A three-dimensional model of a jet was generated in Fluent 6.3 by using large eddy simulation (LES) to reveal the unsteady ground vortices and turbulence characteristics of fluid flow, to investigate transient parameters of hot gases in the jet and their dispersion for further concentration evaluation (Zaporozhets et al., 2017). Thus, the longitudinal coordinate of buoyancy effect calculated by Fluent 6.3 is longer on ~30% while the height of jet rise is ~3 times lower in comparison with semi-empirical jet transport model of the PolEmiCa. ...
... The increase of longitudinal coordinate and decrease of the height of buoyancy rise of the jet leads to reduce air contaminants dilution by jet and to increase the concentration near to ground surface (Zaporozhets et al., 2017). The dispersion model is based on the solution of the turbulent diffusion equation. ...
Emission inventories analysis at European and Ukrainian airports highlighted that aircraft is a dominant source of air pollution. To evaluate the aircraft contribution in airport air quality, it is important to consider some features of the aircraft, as a special source of air pollution. For the most part of landing-take-off cycle, the aircraft is maneuvering on the ground, and it is subjected to fluid flow that can create a strong vortex between the ground and engine nozzle, which have essential influence on structure and basic mechanisms of exhaust gases jet from aircraft engine. The paper demonstrates the results of CFD modeling and analysis for the jets close to ground surface, simulating the aircraft engine jets’ performances in airport. The numerical simulation of wall jet by Fluent 6.3 was implemented for different combination of initial jet velocity and height of engine installation to evaluate the influence of the ground on jet’s parameters (height and longitudinal coordinate of buoyancy effect, length of jet penetration). Obtained results provide improvement of PolEmiCa model.KeywordsAir pollutionAircraft engine emissionsLocal air qualityAircraft engine exhaust gases jetNumerical simulations of jet
Many studies have investigated air-traffic impact on airport air quality through main-engine emissions, however very few have characterized the APU-related impact. As field-monitoring remains limited, our study used CFD simulations to provide a high-fidelity representation of 19 APU dispersion plumes in a realistic airport configuration. Results of three dominant wind configurations show that the global dispersion plume (from all APUs) was transported by incident winds. Depending on wind direction, pollutant trapping within a large downwash region was observed downstream of the terminal-building. Local differences were observed depending on source locations; emissions within the downwash region were pushed against the terminal-facade which promoted emission spillover on terminal-roof, while plumes within the unperturbed boundary layer were transported by incident winds. Quantitatively, APU pollutant concentrations dropped overall by 3–4 orders of magnitude around the terminal-building, while diluted concentrations by 5–6 orders of magnitude were monitored at the airport exit. Given source concentrations with an appropriate experimental apparatus, this model can serve as an airport air quality decision-making tool to finely characterize individual source impacts. Such information can help assist airport operation management (taxi to gate/runway, gate assignment, safe corridors for ground-handling personnel) so as to reduce/prevent the impact of pollutant hot spots depending on wind configurations.
Airport-related pollution is quantified using an idealized numerical environment. 14-hour large-eddy simulations are run over a fictitious but representative regional airport under an academic wintertime anticyclonic situation with the atmospheric model Meso-NH. A simplified photo-chemical module is used and the model is coupled with an emission inventory providing realistic traffic conditions over a 0600-2000 UTC cycle. The emission inventory only includes aircraft related pollutants sources allowing us to isolate and quantify their contribution to local pollution. Two simulations are run in order to characterize the fine scale spatio-temporal evolution of the plume under simple and double traffic activity. Starting from an idealized quiescent and clean atmosphere, the NO2 concentrations reached over the platform range from 10¹ to 10⁴μg.m⁻³. The air quality standards are transgressed near the emissions sources and over a large portion of the platform when the atmosphere is stably stratified. On a larger-scale, the airport-related emissions contribute to NO2 levels up to at least 50 μg.m⁻³ over several square kilometers. The size of the areas affected by the plume is very sensitive to the traffic activity and grows at a rate which is higher than the activity increase itself. Conversely, a twofold augmentation of the traffic results in a less than twofold NO2 concentrations increase because of the non-linearity of the photo-chemical activity. Future contributions could be conducted with a more realistic configuration in order to quantify the interactions between this airport-related plume and the surrounding emissions.
The growth of world aviation traffic leads to an increase of the impact on the environment that is now becoming one of the main factors determining the development of the aviation industry.
Computational fluid dynamics (CFD) has become an attractive tool to predict pollutant concentration in the real environment. CFD software represents the most advanced mathematics that can be applied to simulation different physical process, including the transfer and dilution of fluid flow from aircraft, vehicle and other sources. This paper is an attempt to compare numerical simulation results of exhaust gases jet from aircraft near aerodrome surface by three CFD codes: Fluent 6.3, OpenFOAM and SolidWorks. The work is also focused on assessment of the aerodrome surface influence on jet’s parameters (height and longitudinal coordinate of buoyancy effect) and on providing of initial data for further dispersion modeling. The obtained results are also aimed to improve complex model PolEmiCa.
