Accession Number:

ADA329579

Title:

Nonlinear Laser Diagnostics for Combustion and Plasma Processes.

Descriptive Note:

Final rept. 15 Apr 94-14 Apr 97,

Corporate Author:

SRI INTERNATIONAL MENLO PARK CA

Report Date:

1997-06-11

Pagination or Media Count:

37.0

Abstract:

Significant milestones for quantitative laser-based diagnostics of reacting flows were reached on two separate tasks 1 the extension of laser-based diagnostics to shorter vacuum ultraviolet vuv wavelengths and 2 the development of amplified spontaneous emission ASE diagnostics for light atoms. For the first task, phase-matching was applied to produce significant increases in vuv laser intensities, producing over 5 mu J at Lyman alpha 121.6 nm in a mixture of krypton and argon. Factors affecting the long-term stability of vuv powers were studied. The diagnostic potential of two-photon excited ASE of atomic hydrogen and oxygen was explored in a variety of low-pressure flames. Direct ASE gain measurements gave oxygen concentrations. A model of the ASE signal was developed, and a new understanding of both ASE and laser-induced fluorescence of two-photon excited atoms emerged from this model.

Subject Categories:

  • Lasers and Masers
  • Plasma Physics and Magnetohydrodynamics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE