Accession Number : AD0742101

Title :   Vibrational Relaxation of CO2 in Expanding Flows.

Descriptive Note : Final technical rept. 1 May 67-31 Dec 71,

Corporate Author : CORNELL AERONAUTICAL LAB INC BUFFALO N Y

Personal Author(s) : Russo,Anthony L.

Report Date : JAN 1972

Pagination or Media Count : 56

Abstract : Vibrational relaxation of CO2 with Ar, N2, and CO and the vibrational relaxation of pure CO have been studied in shock-tube driven, quasi-steady supersonic expansion flows in a two-dimensional wedge nozzle. The experiments were conducted over a range of reservoir temperatures of about 2500K to about 4000K and at a reservoir pressure of about 20 atm. The diagnostic technique was based on quantitative measurements of infrared radiation from CO2 and the CO fundamental vibration-rotation band. The results indicate that the vibrational relaxation of CO(v3) in the expansion flows proceeds at a rate nearly that obtained from shock wave studies. The efficiency of argon in deexciting CO2 vibration is estimated. CO is found to relax vibrationally about two orders of magnititude faster than anticipated on the basis of shock-wave results. The results of CO/CO2 mixtures indicate strong coupling of the vibrational deexcitation of these species. (Author)

Descriptors :   (*CARBON DIOXIDE, RELAXATION TIME), EXCITATION, INTERACTIONS, ELECTRON TRANSITIONS, ARGON, NITROGEN, CARBON MONOXIDE, SHOCK WAVES, VIBRATION, MOLECULAR ENERGY LEVELS, EMISSIVITY, GAS LASERS, INFRARED LASERS

Subject Categories : Lasers and Masers
      Atomic and Molecular Physics and Spectroscopy

Distribution Statement : APPROVED FOR PUBLIC RELEASE