The MERMOSE project: Characterization of particulate matter emissions of a commercial aircraft engine

The French national project MERMOSE gathers the capabilities of seven organizations to better characterize commercial aircraft engine emissions and to better understand their impact on nucleation processes in the atmosphere. In this frame, a measurement campaign has been performed on a Snecma/NPO Saturn SaM146-1S17 turbofan. During this work, we used a complete set of on-line and off-line techniques to measure radial and angular profiles of particulate matter (PM) properties in the engine exhaust hot flow. We studied different engine thrust settings, selected to match the aircraft main operating conditions (idle, climb, take-off, approach and "ground" cruise). The mode of the emitted particles size distribution ranged from 17 nm to 55 nm and was sensitive to the thrust. The sampled PM showed a complex morphology and were formed by primary nanoparticles of about 15 rim in diameter. They were mainly composed of carbon (with traces of oxygen, sulfur and calcium) and their organic carbon to total carbon ratio (OC/TC) ratio showed a decrease as a function of the maximum thrust from similar to 80% for 30% thrust setting to similar to 12% for 100%.