A First: The Mapping of Aircraft Engine Exhaust Emissions
In order to better understand the link between aeronautical fine-particle emissions and the formation of condensation trails in aircraft wakes, ONERA has implemented, together with Snecma, the MERMOSE test campaign to finely characterize gaseous chemical species and particulate matter emissions of a complete aircraft engine.
In June 2013, at Villaroche, ONERA performed the MERMOSE test campaign in collaboration with the engine manufacturer Snecma, to characterize the emissions of the PowerJet SaM146 regional aircraft engine (co-developed by Snecma and NPO Saturn). IRSN, the French Institute for Radiological Protection and Nuclear Safety, and CiNaM, the Interdisciplinary Center of Nanosciences at Marseille, complemented ONERA’s expertise in the field of Aerosol science.
This project is supported by the French Civil Aviation Authority (DGAC) within the framework of the Civil Aeronautics Research Council (CORAC).
This campaign, a world first at this level, achieved its goal: complete mapping of engine exhaust emissions for realistic operating conditions. These measurements, the basis for new fundamental studies on soot atmospheric reactivity, will make it possible to improve the level of predictability of aerosol formation theoretical models. Addressing such an issue is part of the efforts to understand the formation of condensation trails suspected of having a detrimental effect on the climate.
The robotic probe collects the particles at different points of the engine exhaust plane
The measurements, performed using a robot carrying a probe, contribute useful knowledge for the validation of a future measurement protocol applicable to the air transport industry, allowing fine particle emissions to be quantified. The challenge: a future certification standard for aircraft engines, relating to air quality, to which ONERA can contribute its expertise in aeronautical engine emission measurement.
In addition, a series of tests allowed many items of data to be gathered regarding emissions collected during the use of an alternative aviation fuel of the national program CAER. The fuel tested was a mixture of kerosene and farnesane (10%), a product developed from sugar cane by Total and the start-up Amyris. The results of this test campaign will participate in the certification of this new line of fuel.
Finally, another campaign is planned for 2014, with the deployment of the MERMOSE measurement chain using ONERA’s M1 test bench in Palaiseau, which is a facility capable of reproducing the operating conditions of an engine at cruise. Thus, emissions downstream from a tubular sector of the combustion chamber of the SaM146 will be investigated. The comparison of the results obtained from these two campaigns is expected to highlight the differences between the emissions of a complete modern engine and those of a sector of its chamber.
For more information, see: http://mermose.onera.fr
For more information about the M1 test bench see:
http://www.airtn.eu/downloads/onera-banc-m1.pdf