New SAE International Standard Details Process for Estimating Non-Volatile Particulate Matter of Aircraft Gas Turbine Engines

SAE International announces the new Aerospace Recommended Practice “ARP6481: Procedure for the Calculation of Non-Volatile Particulate Matter Sampling and Measurement System Losses and System Loss Correction Factors.”

This new standard describes a method for assessing size dependent particle losses in a sampling and measurement system of specified geometry utilizing on the non-volatile PM (nvPM) mass and number concentrations measured at the end of the sampling system. The penetration functions of the sampling and measurement system may be determined either by measurement or by analytic computational methods. Loss mechanisms including thermophoretic (which has a very weak size dependence) and size dependent losses are considered in this method along with the uncertainties due to both measurement error and the assumptions of the method. The results of this system loss assessment allow development of estimated correction factors for nvPM mass and number concentrations to account for the system losses facilitating estimation of the nvPM mass and number at the engine exhaust nozzle exit plane.

The body of the ARP6481 details the recommended calculation method, uncertainties and limitations of the system loss correction factors. It explains, in detail, the required inputs and outputs from the supplied Excel® software tool.

To learn more about this new standard, or to purchase it, visit
Credentialed members of the media may request to review a copy of ARP6481 by emailing or calling 724-772-8522.

ARP6481 was developed by the SAE E-31 Aircraft Emissions Measurement committee. The E-31 committee addresses all facets of aircraft exhaust emissions measurement–tools, methods, processes, and equipment. It is responsible for standardizing measurement methods of emissions from aircraft, including isolated combustor systems. The group is comprised of four subcommittees dedicated to creating, preparing, and maintaining all relevant specifications, standards, and requirements for aircraft exhaust emissions measurement.

SAE International is a global association committed to being the ultimate knowledge source for the engineering profession. By engaging nearly 200,000 engineers, technical experts and volunteers, we drive knowledge and expertise across a broad spectrum of industries. We act on two priorities: encouraging a lifetime of learning for mobility engineering professionals and setting the standards for industry engineering. We strive for a better world through the work of our philanthropic SAE Foundation, including programs like A World in Motion® and the Collegiate Design Series™.
- -
  Continue reading »