**Abstract**

Although airports provide several benefits for our society, communities in the vicinity of airports are subjected to the deterioration of air quality. Currently, the basic objects of attention are NOx and ultrafine PM due to airport-related emissions. Considered environmental problems are intensified in connection with increasing air traffic, rising tensions of airports expansion and growing cities closer and closer each other, and accordingly growing public concern with air quality around the airport. Aircraft are the dominant and special source of emission and air pollution at airports in most cases under consideration. So, to evaluate the aircraft contribution in LAQ assessment of the airports accurately, it is important to take in mind few features of the aircraft during their landing-takeoff cycle (LTO), which define emission and dispersion parameters of the considered source. The complex model PolEmiCa allows the calculation of the inventory and dispersion parameters of the aircraft engine emissions during the LTO cycles of the aircraft in the airport area. But a clear quantification of aircraft emission contribution to total air pollution is the actual task for development of cost-effective strategies to improve local air quality according to the vicinity of the airport, and to meet regulatory requirements.

**Keywords:** aircraft engine emission, exhaust gases jet, airport air pollution, local air quality, modeling of air pollution, emission inventory

### **1. Introduction**

Despite significant economic and social benefits the aviation brings, its activities also contribute to local air quality impact and correspondingly affect the health and quality life of people living near the airports. The number of flights has increased by 80% between 1990 and 2014 and is forecasted to grow by a further 45% between 2014 and 2035. Consequently, the future growth in the European aviation sector will be inextricably linked to its environmental sustainability [1].

During the last decade, a lot of studies have also focused on the aircraft emissions impact on local and regional air quality in the vicinity of airport [2–7]. The basic objects of attention are extremely high concentration of toxic compounds (including nitrogen oxides (NOx), particle matter (PM with various sizes: PM10, PM2.5, and ultrafine), unburned hydrocarbons (UHC), and carbon monoxide (CO)) due to airport-related emissions and their significant impact on the environment [2, 8] and health of the people living near the airport [3, 4].

*Estimated ground-level airport-related emissions from Heathrow Airport.*

Ground-level emissions associated with the airport have the biggest impact on local air quality, whereas elevated aircraft emissions have less impact because they take place at increasing height. **Figure 1** shows aircraft produce approximately 54% of ground-level emissions, whereas airport-related traffic is estimated to emit a

*The emissions inventory of NOx (a) and PM10 (b) within Boryspil International Airport with an intensity*

Analysis of inventory emission results at major European (Frankfurt am Main, Heathrow, Zurich, etc.) and Ukrainian airports highlighted that aircrafts (during approach, landing, taxi, takeoff and initial climb of the aircraft, engine run-ups, etc.) are the dominant source of air pollution in most cases under consideration [6, 9, 10], **Figures 2** and **3**. More than 50% of total NOx emissions inventory inside airport area is released by aircraft engines. As shown in **Figures 2(b)** and **3(b)**,

Considered problems are intensified in connection with rising tensions of expansion of airports and growing cities closer and closer each other (the most urgent is for Ukrainian airports, such as Zhulyany, Boryspil, Lviv, Odessa, and Zaporizhzhia) and accordingly growing public concern with air quality around

the contribution of aircraft emission to total airport PM emissions is

further 28% [5].

*oftakeoffs and landings 50,000 per year.*

*Modeling of Air Pollution at Airports*

*DOI: http://dx.doi.org/10.5772/intechopen.84172*

**Figure 3.**

sufficiently high.

the airport.

**95**

#### **Figure 2.**

*The emissions inventory of NOx [(a) annual emissions: 3.284 tons/year] and PM10 [(b) total emissions: 25 tons/year] within the Frankfurt International Airport for 2005 with an intensity of takeoffs and landings, 1300 per day.*

*Modeling of Air Pollution at Airports DOI: http://dx.doi.org/10.5772/intechopen.84172*

#### **Figure 3.**

**Figure 1.**

**Figure 2.**

**94**

*1300 per day.*

*Estimated ground-level airport-related emissions from Heathrow Airport.*

*Environmental Impact of Aviation and Sustainable Solutions*

*The emissions inventory of NOx [(a) annual emissions: 3.284 tons/year] and PM10 [(b) total emissions: 25 tons/year] within the Frankfurt International Airport for 2005 with an intensity of takeoffs and landings,*

*The emissions inventory of NOx (a) and PM10 (b) within Boryspil International Airport with an intensity oftakeoffs and landings 50,000 per year.*

Ground-level emissions associated with the airport have the biggest impact on local air quality, whereas elevated aircraft emissions have less impact because they take place at increasing height. **Figure 1** shows aircraft produce approximately 54% of ground-level emissions, whereas airport-related traffic is estimated to emit a further 28% [5].

Analysis of inventory emission results at major European (Frankfurt am Main, Heathrow, Zurich, etc.) and Ukrainian airports highlighted that aircrafts (during approach, landing, taxi, takeoff and initial climb of the aircraft, engine run-ups, etc.) are the dominant source of air pollution in most cases under consideration [6, 9, 10], **Figures 2** and **3**. More than 50% of total NOx emissions inventory inside airport area is released by aircraft engines. As shown in **Figures 2(b)** and **3(b)**, the contribution of aircraft emission to total airport PM emissions is sufficiently high.

Considered problems are intensified in connection with rising tensions of expansion of airports and growing cities closer and closer each other (the most urgent is for Ukrainian airports, such as Zhulyany, Boryspil, Lviv, Odessa, and Zaporizhzhia) and accordingly growing public concern with air quality around the airport.

1. **engine emission model**—emission assessment for aircraft engines, including

2. **jet transport model**—transportation of the contaminants by the jet plume

3. **dispersion model**—dispersion of the contaminants in atmosphere due to

The emission inventory of aircraft emissions are usually calculated on the basis of certificated emission indexes, which are provided by the engine manufacturers and reported in the database of the International Civil Aviation Organization (ICAO) [16]. The emission indices rely on well-defined measurement procedure and conditions during aircraft engine certification. Under real circumstances, however, these conditions may vary and deviations from the certificated emission indices may

• the life expectancy (age) of an aircraft—emission of an aircraft engine might vary significantly over the years (the average period is 30 years); usually aging aircraft/engine provides higher emission indices in comparison with same

• the type of an engine (or its specific modification, for example with different combustion chambers) installed on an aircraft, which can be different from an

• meteorological conditions—temperature, humidity, and pressure of ambient

So, the analysis of several measurement campaigns for idling aircraft at different European airports (London-Heathrow in 1999 and 2000, Frankfurt/Main in 2000, Vienna in 2001, and Zurich in 2003) [7] concludes that the largest difference between emission indices' measurement data and the ICAO data for CO for the RB211-524D4 engine was caused due to quite long life expectancy of B747-236 (aging aircraft and engines) (**Figure 5**). The oldest aircraft with an emission index of 52.9 g/kg was 25 years old; the other two were built in 1987 and 1983. Mean values

*Comparison measured EICO by FTIR emission and absorption spectrometry during measurement campaign for*

engine operated in an engine test bed (during certification); and

air, which can be different for certification conditions.

influence of operational factors;

*DOI: http://dx.doi.org/10.5772/intechopen.84172*

*Modeling of Air Pollution at Airports*

from the engine exhaust nozzle; and

turbulent diffusion and wind transfer.

occur due to the impact factors such as

type but new ones;

**Figure 5.**

**97**

*idling aircraft at the European airports.*

**2.1 Emission model**

#### **Figure 4.**

*Jet structure for jet transport model. ΔhA, XA are the height and longitudinal coordinate of jet axis rise due to buoyancy effect, m; hEN is the height of engine installation, m; RB is the radius of jet expansion, m; X1 is the longitudinal coordinate of first contact point of jet with ground, m; and X2 is the longitudinal coordinate of a point of jet lift-off from the ground due to buoyancy effect, m.*

Aircrafts are a special source of air pollution due to some features.

**First of all**, aircrafts are a moving (on the ground and in flight) pollution source with varying emission factors during landing and takeoff (LTO) as well as ground operation (engine start after maintenance and run-ups to check the correct operation of the flight system). At the airport, engine operation may change from idle to maximum thrust. Accordingly, temperature, exhaust gas velocity, and emissions of an aircraft engine may change within a wide range [11].

**Second**, the most important feature is the presence of a jet of exhaust gases, which can transport pollutants over rather large distances because of high exhaust velocities and temperatures (**Figure 4**). Such a distance is determined by the engine power setting and installation parameters, mode of airplane movement, and meteorological parameters. The results of jet model calculations show that depending on initial data, the jet plumes from aircraft engines range from 20 to 1000 m and sometimes even more [11].

So, to evaluate the aircraft contribution in Local Air Quality assessment of the airports accurately, it is important to take in mind few features of the aircraft during their landing-takeoff cycle (LTO), which define emission and dispersion parameters of the considered source.

#### **2. Modeling of air pollution produced by aircraft engine emissions**

Modeling of airport air pollution includes two parts: emission inventory and dispersion calculation.

ICAO Doc 9889 [12] recommends few tools for air quality analysis—to model emission inventory from every character groups of the spatially distributed sources as well as atmospheric concentrations resulting from emission dispersion: EDMS is based on Gaussian plume model (AERMOD) [13], LASPORT is based on Lagrangian particle model (LASAT) [14], and ALAQS–AV provides to use both Gaussian and Lagrangian approaches for dispersion calculations [12].

A complex model Pollution and Emission Calculation (PolEmiCa) for assessment of air pollution and emission inventory analysis, produced within the airport boundaries, has been developed at National Aviation University (Kyiv, Ukraine) [15]. It consists of the following basic components:

