Investigation of Superradiant LDV Markers and Three-Component Velocity Mapping.
Abstract
Consider high intensity laser beam interactions with single transparent micrometer size droplets flowing in the linear stream applied to real time diagnostics of the chemical species contained within droplets of sprays. Research efforts are directed toward exploring the limits of high intensity irradiation of micrometer size transparent droplets. Two effects are considered: (1) the intensity dependent index of refraction of the liquid, which can lead to self focusing of the laser beam within the droplet and to broadening of the Raman radiation and elastic scattering due to phase modulation within the droplet; and (2) laser induced dielectric breakdown, which can occur either in the gas surrounding the droplet or in the liquid within the droplet. The breakdown generates a shock wave and/or an optical detonation wave which causes material to stream from the droplet and form plumes. Success was achieved in developing an optical technique with potential of proving three component velocity mapping in three dimensions. A time coded five pulse volume holography of silver coated hollow spheres seeded in a cold flow has been recorded, and an automated pattern recognition technique (Hough transform) has been adapted to identify straight lines formed by the five exposures of the same silver coated particles, which were sparsely seeded in a nozzle flow.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 30, 1987
- Accession Number
- ADA179732
Entities
People
- Richard K. Chang
Organizations
- Yale University