Nonlinear Spectroscopy of Multicomponent Droplets and Two- and Three- Dimensional Measurements in Flames

Abstract

Our progress in the area of nonlinear spectroscopy of droplets includes the following: 1) development of a fluorescent imaging technique which is capable of demarcating the liquid phase of the deformed and ejected droplets from the vapor phase of the ejected material; 2) determination that the absorption of the laser-induced plasma quenches the stimulated Raman process and sets an upper limit on the incident intensity which can be used to generate stimulated Raman scattering (SRS) within droplets; 3) completion of a statistical study of the SRS from single droplets which are irradiated at a fixed input laser intensity (from a single-mode or a multi-mode laser); 4) conclusion that, for single-mode laser excitation, SRS is pumped by the stimulated Brillouin radiation, not directly by the laser radiation; and 5) initiation of studies on the phase-matching requirement for four-wave mixing processes in droplets and on the phase velocity of waves on a morphology- dependent resonance. Keywords: Nonlinear optical diagnostics; Fluorescence imaging; Stimulated Raman scattering; Phase-matching conditions; Phase velocity of modes; Laser diagnostics; Turbulent flames; Premixed flames; Three- dimensional flow measurements; Burning velocity.

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Document Details

Document Type
Technical Report
Publication Date
Jan 15, 1990
Accession Number
ADA218569

Entities

People

  • Marshall B. Long
  • Richard K. Chang

Organizations

  • Yale University

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Carbon Dioxide Lasers
  • Combustion
  • Detectors
  • Diffusion
  • Electro-Optics
  • Frequency
  • Laser Applications
  • Laser Beams
  • Laser Pulses
  • Laser Spectroscopy
  • Lasers
  • Optics
  • Raman Scattering
  • Rayleigh Scattering
  • Spectroscopy
  • Wave Mixing
  • Yag Lasers

Fields of Study

  • Physics

Readers

  • Combustion science or combustion engineering.
  • Molecular Photonics/Laser Physics
  • Wave Propagation and Nonlinear Chaotic Dynamics.

Technology Areas

  • Directed Energy