Non-Volatile Particle Penetration Efficiencies: UTRC Line Loss Model Validation

The SAE E-31 Aircraft Engine Gas & Particulate Emissions Measurement Aerospace Recommended Practice (ARP) 6320 {Ref. 17} describes procedures recommended for continuous sampling conditions and instrumentation for measurement of non-volatile particle number and mass emissions from the exhaust of aircraft gas turbine engines. Throughout the creation of the ARP, many tests were conducted to determine the best way to collect and measure non-volatile particulate matter from turbine engines to preserve sample integrity and minimize the losses through the system; including sampling, conditioning, and measurement. Based on the results of these tests, a system was built by Missouri University of Science and Technology (MS&T), which they own and operate. A few other in-house systems were built by other organizations, but it wasn’t until Anstalt für Verbrennungskraftmaschinen List (AVL) of Graz, Austria started to produce and manufacture an ARP6320 compliant sampling system that it was commercially available for purchase. The first prototype was delivered to Arnold Engineering Development Complex. Even though the AVL sampling system and the MS&T sampling system are compliant with the ARP6320, there were some differences between the two systems which begged the question, will each system produce the same or similar results? The Environmental Protection Agency (EPA) VAriable Response In Aircraft Non-Volatile Particulate Matter Testing (VARIAnT) 2 was established to answer these questions and more. This thesis concentrates on a small portion of this test campaign, specifically the ability of the systems to transport non-volatile or carbon black particles to instruments for measurement of mass, number, and size. The ratio of non-volatile particle concentration entering and leaving a sampling and measurement system segment is the Penetration Fraction which is the focus of this thesis.

The results in this thesis and other comparisons to the model have shown close correlation within the measurement uncertainties of 14%. The penetration efficiency model used in this work was developed by UTRC and has been improved over the years to account for various differences between measured and predicted. Using the results presented in this thesis, the UTRC model presents a better alternative to the measurements of the penetration efficiencies for the ARP compliant sampling systems.