Review: Particulate Matter Emissions from Aircraft

Abstract

The contribution of aircraft operations to ambient ultrafine particle (UFP) concentration at and around airports can be significant. This review article considers the volatile and non-volatile elements of particulate matter emissions from aircraft engines, their characteristics and quantification and identifies gaps in knowledge. The current state of the art emission inventory methods and dispersion modelling approaches are reviewed and areas for improvement and research needs are identified. Quantification of engine non-volatile particulate matter (nvPM) is improving as measured certification data for the landing and take-off cycle are becoming available. Further work is needed: to better estimate nvPM emissions during the full-flight; to estimate non-regulated (smaller) engines; and to better estimate the emissions and evolution of volatile particles (vPM) in the aircraft exhaust plume. Dispersion modelling improvements are also needed to better address vPM. As the emissions inventory data for both vPM and nvPM from aircraft sources improve, better estimates of the contribution of aircraft engine emissions to ambient particulate concentrations will be possible.

Comparison of Particle Sizers and Counters with Soot-like, Salt, and Silver Particles

“…European regulations introduced the particle number (PN) method and many other Asian countries followed [6][7][8]. PN measurements are also conducted in the aviation field [9] and are under discussion for brakes from vehicles [6]. The PN concentration is determined with a condensation particle counter (CPC) [10,11].…”

Uncertainties in mitigating aviation non-CO2 emissions for climate and air quality using hydrocarbon fuels

“…At present, RQL combustion systems are more widely used and based on the physical understanding of the processes in the combustor, the tradeoff between NO x and nvPM should be more signicant than for lean burn engines. 41 Water injection has also been suggested as a means to limiting NO x emissions. 42 Water ingestion into the air stream ahead of the combustor will lower the temperature of the air entering the combustor and will therefore reduce the formation of NO x .…”

“…At present, RQL combustion systems are more widely used and based on the physical understanding of the processes in the combustor, the tradeoff between NO x and nvPM should be more significant than for lean burn engines. 41…”

Breathing Fresh Air in the City: Implementing Avenue Trees as a Sustainable Solution to Reduce Particulate Pollution in Urban Agglomerations

“…These procedures, which can change a particle’s makeup or enlarge it, proceed in three phases. The formation of the first nuclei or particles in the atmosphere occurs in the nucleation mode [ 80 ], which is dependent on gas concentration, temperature, and humidity in the atmosphere [ 81 ], as well as the conversion of the gaseous phase to a liquid or solid by condensation or chemical reaction [ 62 ]. Primary aerosols are created in the second stage, which is the condensation of heated gases.…”