The Earth Atmosphere and the Aviation: Problem and Research Goals
O.Favorsky, A.Starik
The production activity of the mankind has caused during the last decades a considerable change of the gas and aerosol composition of the atmosphere. One of the sources of direct influence upon the atmosphere is the aviation. The absolute quantity of substances emitted into the atmosphere from aircraft engines is 40 to 50 times smaller than the pollution from surface sources (power generation, transport, industry, agriculture). But those emissions occur directly in the atmospheric layers which are very sensitive to any kind of disturbances (the upper troposphere and the lower stratosphere), that's why the determination of the real influence of the aviation upon atmospheric processes and upon the Earth climate is getting more and more important....
...The strategy and the main sections of the investigations of the aviation influence upon the atmosphere can be illustrated by the scheme shown in Fig. 1...
...Because the typical retention time of the gas in the combustion chamber is about 5-20 ms, and the time needed to obtain the balanced state is up to 20 s, it becomes clear that the gas composition at the combustion chamber outlet is considerably unbalanced in its small components...
...Earlier it was shown, that the engine jet of each aircraft carries electrical current ("carried-away current") caused by the charged solid phase micro-particles and ions. The ions getting into the oversaturated area of the engine jet give rise to additional condensation and usually increase the total surface of the formed aerosols. This can have an essential influence upon the characteristics of atmospheric aerosols in general. These effects are also a subject of investigations.
A key experiment was performed under laboratory conditions when ions of a corona discharge were introduced into a steam/air jet. As a result, the condensed dispersion phase (aerosol) build-up increased by 1-2 orders. The scheme of the experiment is shown in Fig. 3.sFurthermore, it was shown in a flying laboratory that additional introduction of ions by means of specially designed devices can have essential influence upon the condensation in the aircraft trace - Fig. 4...
...The aim of the present paper is to analyze the modern state of investigations of the aviation influence upon the atmospheric processes and to show the main directions of further investigations. Those could be aimed at possible improvements of the requirements to the aircraft engines exhaust gas composition (those requirements are still primitive today) and probably of the requirements to aircraft fuels and at the acquisition of more realistic input data for global simulation of the influence of jets aircrafts on the atmosphere and further on the climate and the ozone layer. All the above stated must be taken into account when choosing the influence scenarios for estimation of the aviation influence upon the atmosphere.
Oleg N. Favorsky, professor, doctor of science, Academician, Head of Department of Physical and Technical Problems of Energetic, Deputy director of Central Institute of Aviation Motors. He is a specialist on aviation engine and gas turbine energetic stations, an author of 5 monographs and 150 articles, senior manager of 5 gas turbine engine (1973-1987).
Alexander M. Starik, professor, doctor of science, Head of research group in Central Institute of Aviation Motors. He is a specialist on chemical physics, Physics of atmosphere, laser physics and nonequilibrium gasdynamic, an author of 170 articles and 60 patents.
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