Characterization of Simulated Weather and Turbine Exhaust nvPM Mass

Hypersonic missile and glider development have become of paramount importance and has accelerated as a result of recent announcements regarding deployments by other countries. With flight speeds as high as Mach 10 to 27, atmospheric particulate including water droplets, snow, ice particles, graupel, etc. can impart severe damage to these vehicles with the potential of initiating failure in flight. Investigations of such impact characteristics and the development of protection systems involves extensive ground testing in hypersonic ranges. These tests require reliable in situ measurements of the various atmospheric particulate. Under this proposed program, advanced imaging systems are proposed that can characterize the atmospheric particulate for the development of a complete database of the size, shapes, and mass of particles that may be encountered by the hypersonic vehicles. These data on the atmospheric particulate will then be simulated in ground test facilities. High-speed imaging systems will be developed and made available to characterize these particulates to ensure that accurate simulations will be available. This effort will lead to the development of advanced three-dimensional imaging systems for the AEDC G-Range facility to provide data on simulated particulates. An airworthy high-speed imaging (HSI) flight probe will be developed for acquiring the in situ atmospheric particulate data needed for the simulations. A hardened imaging system for hydrometeor characterization will be developed to meet the requirements of the Holloman AFB HSTT to help the design of simulated rain conditions on the hypersonic test track.  There is a compelling need to characterize the total emissions from aircraft engines including CO2, NOX, SOX, aerosol, and nonvolatile particulate matter (nvPM). Methods to characterize nvPM concentrations, size distributions, and number density that are fast and reliable are in high demand. Under this program, laser induced incandescence (LII) instruments will be refined and evaluated for measuring nvPM mass emissions and will provide additional information on the particulate specific surface area. This development will result in the refined LII instrument and the evolution of calibration means that will ensure reliable and accurate mass emissions characterizations. Integration of the LII instrument with the differential mobility analyzer (DMA), the condensation particle counter (CPC) and CO2 monitor will result in the availability of instrumentation to fully characterize nvPM emissions. These instruments will be refined in the laboratory and then will undergo thorough testing at AEDC/UTSI using the J 85 jet engine and operated on a wide range of fuels. Questions to be addressed include problems with calibration means and soot generation, possible dependencies on soot aggregate particle size and primary particle size, and consistency in the calibration means when the instrument is applied to a range of combustion systems.