Considerations on the Retrieval of Plume Particle Properties from the AFRPL Transmissometer and Polarization-Scattering Experiments.
Abstract
Assessment is made of the usefulness of data currently being obtained in two particle-diagnostic experiments at Air Force Rocket Propulsion Laboratory. In one experiment, simple laser transmission measurements are made over a full diameter line of sight through the plume. It is shown that the measured degree of beam attenuation caused by plume particle absorption and scattering, and from auxiliary knowledge of the total mass loading in the plume, a measure of the mean particle size can be deduced to accuracies of < 20% even when the index of refraction and size distribution of the particles are relatively unknown. In the second experiment, measurements are made of the polarization of the laser light as it is scattered through angles of 15 to 150 degrees. It is shown, that for the conditions under which these data are currently taken, there is little hope of obtaining any information on particle size or size distribution. As a preliminary step to the assessment of the polarization/scattering diagnostic, an analysis is made of a three-color laser scattering diagnostic that could lead to successful particle size distribution retrieval.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1984
- Accession Number
- ADA145353
Entities
People
- S. J. Young
Organizations
- The Aerospace Corporation