Particle Sampling System Designed to Simulate Aging of Aircraft Exhaust Plumes

ARI is developing an aircraft exhaust sampling system that transitions condensable species to the condensed phase in a manner that mimics what happens when the exhaust is emitted into the atmosphere. Standard engine-exit plane measurements are not suitable for these volatile particles because they form downstream of the aircraft as the exhaust plume mixes with ambient air and cools. Downstream measurements are impractical because the results are highly sensitive to the ambient weather conditions. A prototype Simulated Aircraft Exhaust Plume Aging (SAEPA) probe has been developed that mimics the time-varying thermal environment experienced by exhaust plumes under standard-day conditions. Under Phase I, detailed numerical simulations of the relevant aerosol microphysical processes were used to design the SAEPA prototype, which was then fabricated and tested using a laboratory combustion source. In Phase II, we propose to conduct further design calculations, laboratory tests, and field tests necessary to transition the current prototype to a commercial product.