Non-Volatile Particulate Matter Control for Aviation

Current regulations to control aircraft exhaust particulates employ the SAE Smoke Number Measurement ARP1179 technique to evaluate the visibility of the exhaust at the exit plane of gas turbine engines. Particulate Matter (PM)... [ view full abstract ]

Current regulations to control aircraft exhaust particulates employ the SAE Smoke Number Measurement ARP1179 technique to evaluate the visibility of the exhaust at the exit plane of gas turbine engines. Particulate Matter (PM) consists of volatile and non-volatile components. It is proposed to regulate submicron non-volatile Particulate Matter (nvPM) emissions in the near future due to public concerns of their impact on global warming and human health effects around the airports. More detailed measurement of the mass and number count of these particle emissions are required than the SAE Smoke Number. Responding to the regulatory agency requests, AIR6241 describes measurement techniques that are well developed and can be applied to the measurement of aircraft engine exhaust particulate matter.

To be supportive of a sustainable global environment and clean air quality around local airports, Pratt & Whitney Canada initiated a GARDN funded project that followed this SAE AIR procedure to build an nvPM measurement system. The subsystems were constructed and verified with a soot generator at the university. The completed system was then installed at a P&WC engine test cell. A separate nvPM measurement reference system was also set up in the same test cell. A small gas turbine engine was run with the two nvPM measurement systems applied back-to-back in two consecutive days to obtain PM emissions data at the engine exhaust plane. This was the first test of the entire measurement system on a real gas turbine engine using the emissions probes mandated by ICAO exhaust gas sampling requirements. Test data were analysed and compared. It was concluded that the above engineering experiments, according to the AIR6241 specifications and procedures, produced engine data that agreed to within 24% of the reference system. This project provided additional experimental information for considering the developed methodology as the routine aircraft engine measurement for future PM regulations. Transport Canada and P&WC are collaborating to support the development of international regulations to control aircraft pollutants through ICAO.