Potential Ozone Column Increase Resulting from Subsonic and Supersonic Aircraft NOX Emissions

The new generation of jet powered aircraft faces a significant challenge to reduce pollutant emissions while increasing fuel efficiency. Carbon monoxide (CO) and unburned hydrocarbon (HC) emissions are already very low and continued control of these pollutants is expected as engine temperatures and pressure ratios are increased. In contrast, significant system design improvements are needed to reduce oxides of nitrogen (NOx) emissions because of their harmful effect on the earth’s ozone layer. This paper discusses the prospects and technical approaches for significant NOx reductions in current and future subsonic and supersonic aircraft.

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Aircraft Gas Turbine Emissions Challenge

Volume 3C: General ◽

10.1115/93-gt-422 ◽

1993 ◽

Cited By ~ 6

Author(s):

B. L. Koff

Keyword(s):

Fuel Efficiency ◽

Harmful Effect ◽

Pollutant Emissions ◽

Nox Emissions ◽

Oxides Of Nitrogen ◽

Supersonic Aircraft ◽

Significant Challenge ◽

Unburned Hydrocarbon ◽

Hc Emissions ◽

New Generation

The new generation of jet powered aircraft faces a significant challenge to reduce pollutant emissions while increasing fuel efficiency. Carbon monoxide (CO) and unburned hydrocarbon (HC) emissions are already very low and continued control of these pollutants is expected as engine temperatures and pressure ratios are increased. In contrast, significant system design improvements are needed to reduce oxides of nitrogen (NOx) emissions because of their harmful effect on the earth’s ozone layer. This paper discusses the prospects and technical approaches for significant NOx reductions in current and future subsonic and supersonic aircraft.

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Aircraft pollution: a futuristic view

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-7-2531-2007 ◽

2007 ◽

Vol 7 (1) ◽

pp. 2531-2560 ◽

Cited By ~ 3

Author(s):

O. A. Søvde ◽

M. Gauss ◽

I. S. A. Isaksen ◽

G. Pitari ◽

C. Marizy

Keyword(s):

Southern Hemisphere ◽

Northern Hemisphere ◽

Total Ozone ◽

Transport Processes ◽

Ozone Production ◽

Aircraft Emissions ◽

Total Ozone Column ◽

Ozone Loss ◽

Supersonic Aircraft ◽

Ozone Column

Abstract. Impacts of NOx, H2O and aerosol emissions from a projected 2050 aircraft fleet, provided in the EU project SCENIC, are investigated using the Oslo CTM2, a 3-D chemical transport model including comprehensive chemistry for the stratosphere and the troposphere. The aircraft emission scenarios comprise emissions from subsonic and supersonic aircraft. The increases in NOy due to emissions from the mixed fleet are comparable for subsonic (at 11–12 km) and supersonic (at 18–20 km) aircraft, with annual zonal means of 1.35 ppbv and 0.83 ppbv, respectively. H2O increases are also comparable at these altitudes: 630 and 599 ppbv, respectively. The aircraft emissions increase tropospheric ozone by about 10 ppbv in the Northern Hemisphere due to increased ozone production, mainly because of subsonic aircraft. Supersonic aircraft contribute to a reduction of stratospheric ozone due to increased ozone loss at higher altitudes. In the Northern Hemisphere the reduction is about 39 ppbv, but also in the Southern Hemisphere a 22 ppbv stratospheric decrease is modeled due to transport of supersonic aircraft emissions and ozone depleted air. The total ozone column is increased in lower and Northern mid-latitudes, otherwise the increase of ozone loss contributes to a decrease of the total ozone column. Two exceptions are the Northern Hemispheric spring, where the ozone loss increase is small due to transport processes, and tropical latitudes during summer where the effect of subsonic aircraft is low due to a high tropopause. Aerosol particles emitted by aircraft reduce both aircraft and background NOx, more than counterweighting the effect of NOx and H2O aircraft emissions in the stratosphere. Above about 20 km altitude, the NOx (and thus ozone loss) reduction is large enough to give an increase in ozone due to aircraft emissions. This effect is comparable in the Northern and Southern Hemisphere. At 11–20 km altitude, however, ozone production is reduced due to less NOx. Also ClONO2 is increased at this altitude due to enhanced heterogeneous reactions (lowered HCl), and ClO is increased due to less NOx, further enhancing ozone loss in this region. This results in a 14 ppbv further reduction of ozone. Mainly, this results in an increase of the total ozone column due to a decrease in ozone loss caused by the NOx cycle (at the highest altitudes). At the lowermost latitudes, the reduced loss due to the NOx cycle is small. However, ozone production at lower altitudes is reduced and the loss due to ClO is increased, giving a decrease in the total ozone column. Also, at high latitudes during spring the heterogeneous chemistry is more efficient on PSCs, increasing the ozone loss.

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Aircraft Cruise Nitrogen Oxides (NOx) Emissions Prediction and Environmental Pollution Factor

Energy & Environment ◽

10.1260/0958-305x.18.5.565 ◽

2007 ◽

Vol 18 (5) ◽

pp. 565-575 ◽

Cited By ~ 2

Author(s):

Louis Tsague ◽

Thomas Tamo Tatietsé

Keyword(s):

Nitrogen Oxides ◽

Data Bank ◽

Health Concern ◽

Nox Emissions ◽

Commercial Aircraft ◽

Supersonic Aircraft ◽

Limit Value ◽

Pollution Factor ◽

Predictive Correlation ◽

Set Up

Nitrogen oxides (NOx) emitted at low altitude increase ozone formation, thus potentially affecting local air quality. On the other hand supersonic aircraft NOx emitted in the lower stratosphere deplete the ozone layer, which represents a serious health concern according to Richard Miake Lyea and Ulrich Schumannb). The necessity to evaluate aircraft NOx production at cruise is urgent, since ICAO standard on NOx limitations has not yet taken into account cruise NOx emissions. The purpose of this work is to solve the problem of aircraft cruise NOx emissions regulation. The evaluation of nitrogen oxides production according to operational time in mode is realized with the ICAO data bank from different types of aircraft engines. Cruise NOx production is compared to LTO NOx production. A predictive correlation linking cruise NOx production to flight distance is developed and evaluated with good accuracy. Although cruise NOx production prediction is very important, alone it may not be enough to settle a limitation regulation on cruise NOx emissions, then the maximum flight range and the maximum take off weight, as those important factors influencing the NOx emissions are taken into account to develop a specific NOx production parameter which can enable the commercial aircraft classification according to their pollution factor, by so doing, ICAO NOx emissions regulation can be completed using the approach we propose to set up a limit value on aircraft cruise NOx emissions.

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Reduction of Stratospheric Ozone from High-flying Aircraft, Studied in a Two-dimensional Photochemical Model with Transport

Canadian Journal of Chemistry ◽

10.1139/v74-231 ◽

1974 ◽

Vol 52 (8) ◽

pp. 1592-1598 ◽

Cited By ~ 20

Author(s):

Eigil Hesstvedt

Keyword(s):

Reasonable Agreement ◽

Column Density ◽

Stratospheric Ozone ◽

Two Dimensional ◽

Dimensional Model ◽

Supersonic Aircraft ◽

Stratospheric Ozone Layer ◽

Two Dimensional Model ◽

Flight Level ◽

Ozone Column

A steady state two-dimensional model of the stratospheric ozone layer is presented. Chemical reactions involving oxygen, hydrogen, and nitrogen are considered along with the effect of a parameterized, two-dimensional transport, by mean motion and by eddies. The model is in reasonable agreement with observed ozone data. The reduction of ozone from emission of NOx from high flying aircraft is studied, assuming a fleet of 500 supersonic aircraft in transatlantic operation, flying at given altitudes. The effect is found to depend critically upon flight level. For mid-latitude, summer, the ozone column density is reduced by 0.3% for a flight level of 18 km. For flight levels of 23 and 28 km the reduction is 2 and 5%, respectively. Accordingly, the increase in u.v. radiation amounts to approximately 0.6, 4, and 10% for the same flight levels.

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Aircraft Turbine Engine NOx Emission Limits: Status and Trends

Volume 2: Aircraft Engine; Marine; Microturbines and Small Turbomachinery ◽

10.1115/92-gt-415 ◽

1992 ◽

Cited By ~ 3

Author(s):

D. W. Bahr

Keyword(s):

Nox Emission ◽

Future Generations ◽

Nox Emissions ◽

Aircraft Engines ◽

Turbine Engine ◽

Supersonic Aircraft ◽

Status And Trends ◽

Civil Aircraft ◽

Percent Increase ◽

Emission Limits

Within recent years, the NOx emissions of aircraft engines have received increased attention. More stringent limits on the NOx emissions of future subsonic civil aircraft engines are being considered. A 20 percent increase in the stringency of the existing ICAO standard has been proposed and, for the longer-term, the possibility of further increased stringency is being studied. For future supersonic civil aircraft engines, very stringent goals have been established. To meet these goals, combustor designs with ultralow NOx levels are required. Extensive efforts are, therefore, underway to develop low NOx combustors for use in future generations of both subsonic and supersonic aircraft engines.

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