Accession Number : AD0751016

Title :   CO2 Laser Radiation Absorption in SF6-Air Boundary Layers,

Corporate Author : NAVAL ORDNANCE LAB WHITE OAK MD

Personal Author(s) : Anderson,John D. , Jr. ; Wagner,Jerry L. ; Knott,Joseph

Report Date : 01 AUG 1972

Pagination or Media Count : 70

Abstract : Previous investigators have shown that gaseous sulfur hexafluoride (SF6) is a strong absorber of radiation at 10.6 micrometers. This wavelength also corresponds to the output from common CO2 lasers. New experimental and theoretical results are presented for the 10.6 micrometers absorption coefficient and saturation properties of SF6-air mixtures at conditions near standard sea level. Variations with pressure, wavelength and temperature are measured. Results for 10 percent SF6-90 percent air at 1 atm show that such mixtures are stron absorbers of CO2 laser radiation, and that saturation intensities are larger than 10,000 watts/sq cm. Measurements of CO2 laser radiation absorption within boundary layers with SF6 injection are made on the sidewall of a small subsonic wind tunnel. The beam intensity is attenuated by several orders of magnitude due to absorption by the SF6. (Author)

Descriptors :   (*FLOW FIELDS, CONTROL SYSTEMS), GAS LASERS, INFRARED LASERS, SULFUR COMPOUNDS, FLUORIDES, ABSORPTION SPECTRA, HEATING, WIND TUNNEL MODELS

Subject Categories : Fluid Mechanics
      Optics

Distribution Statement : APPROVED FOR PUBLIC RELEASE