Accession Number : ADA264341


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


Descriptive Note : Annual rept. 1 Feb 92-31 Jan 93,


Corporate Author : YALE UNIV NEW HAVEN CT DEPT OF APPLIED PHYSICS


Personal Author(s) : Chang, Richard K ; Long, Marshall B


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a264341.pdf


Report Date : 05 Mar 1993


Pagination or Media Count : 24


Abstract : Significant progress has been made in the following areas: (1) Nonlinear spectroscopy of micrometer sized droplets, and (2) Development and application of two- and three-dimensional scalar and velocity measurement techniques in flames. In the nonlinear spectroscopy area, the following achievements are reported: (1) Fluorescence seeding of the stimulated Raman scattering (SRS) in order to increase the detectivity (by as much as 10X) of minor species in a multicomponent liquid droplet that contains a fluorescent dye; (2) Temporal precession of the SRS as a means of determining the shape distortion (7 parts out of 10(exp 3)) of a flowing droplet because of inertial force; (3) Preliminary measurements of the relative evaporation rates of 15 droplets in a segmented stream where the few lead droplets evaporate faster than the remaining droplets; and (4) Suppression of lasing by the SRS and amplification of the SRS in microdroplets, leading to an increased SRS signal. . .. Droplets, Spray, Evaporation rate, Shape distortion, Precession of cavity modes and Lasing, Premixed flames, Nonpremixed flames, Rayleigh scattering, Laser-induced fluorescences, Three-dimensional measurements, Laser diagnostics, Flow imaging, Supersonic flow, Mixture fraction and Scalar dissipation.


Descriptors :   *SPECTROSCOPY , *NONLINEAR OPTICS , *FLAMES , VELOCITY , LUMINOSITY , MEASUREMENT , LIQUIDS , TWO DIMENSIONAL , RATES , LASERS , DROPS , IMAGES , SIGNALS , RAYLEIGH SCATTERING , PARTICLES , FUELS , THREE DIMENSIONAL , CHEMICAL COMPOSITION , MIXTURES , STREAMS , SEGMENTED , RAMAN SPECTRA , SUPPRESSION , SPRAYS , DISTORTION , FLUORESCENT DYES , SUPERSONIC FLOW , EVAPORATION , PRECESSION , ACETALDEHYDE , MICROMETERS , SEEDING , CHARGE COUPLED DEVICES , METHANE , AMPLIFICATION , TOMOGRAPHY , SCALAR FUNCTIONS , FLOW , DIFFUSION , DIAGNOSTIC EQUIPMENT , CAMERAS , CAVITIES , DISSIPATION , SHAPE , QUANTITY , SCATTERING , INERTIA , FLUORESCENCE


Subject Categories : Physical Chemistry
      Atomic and Molecular Physics and Spectroscopy
      Optics
      Combustion and Ignition


Distribution Statement : APPROVED FOR PUBLIC RELEASE