Soot particle density determination from a laser extinction multipass technique
Authors
Glaros, Gregory E.
Subjects
NA
Advisors
Biblarz, Oscar
Netzer, David W.
Date of Issue
1994-09
Date
September 1994
Publisher
Monterey, California. Naval Postgraduate School
Language
en_US
Abstract
Methods of measuring soot particle densities have been of interest for several decades. Plume signature determination of both rocket and air-breathing engines is of concern when applied to pollution and theater missile ballistic defense strategies. Application of non-intrusive traditional techniques employing Bouguer's law relied on Sauter mean diameter, statistical deviation and the probability density function in order to compensate for the ambiguities present in the extension of classical Mie theory. Our investigation developed an apparatus which will determine soot particle densities by measuring extinction from absorption of light energy transmitted through an exhaust plume. The method used was a two-pass technique using an optical phase conjugator (OPC) which returned the non-absorbed portion of light energy. When the apparatus was used with a retroreflector, it produced accurate results but did not compensate for thermal blooming or beam steering. Characteristics of a photorefractive crystal used in the OPC process allowed for the return of an incident beam corrected for aberrations. Although the OPC returned the phase conjugate of the incident beam its size precluded the return of all of the transmitted data because data was lost on the blossomed beam.
Type
Thesis
Description
Series/Report No
Department
Organization
Naval Postgraduate School (U.S.)
Identifiers
NPS Report Number
Sponsors
Funding
Format
35 p.
Citation
Distribution Statement
Approved for public release; distribution is unlimited.
Rights
This publication is a work of the U.S. Government as defined in Title 17, United States Code, Section 101. Copyright protection is not available for this work in the United States.