RESEARCH STUDY OF LIGHT EMISSION CAUSED BY PRESSURE FLUCTUATIONS IN ROCKET ENGINES
Final rept. 1 Jan-31 Dec 1965
THIOKOL CHEMICAL CORP DENVILLE NJ REACTION MOTORS DIV
Pagination or Media Count:
The program was to investigate the usefulness of spectroscopy as a diagnostic technique for studying combustion instability in a rocket chamber. Main emphasis was given to investigating pressure and the 3064A OH and 4315A CH emission as a function of time in order to study the time lag between pressure and emission. The 1100 cps longitudinal mode and the 7100 cps tangential mode in a cylindrical motor 3 inches in diameter and 16 inches long were investigated. Two propellant systems were used, a premixed methane-air gaseous system and a liquid pentane-gaseous air system. Optical results were limited in reproducibility, perhaps because of local turbulent combustion phenomena. Time-averaged spectra indicated no other strong spectral lines in the 2800-4400A range but did indicate that a CO O continuum existed and became more intense as the chamber pressure increased and particularly when non- impinging jet injectors were used with pentane-air system. This intense CO O continuum obscures the CH emission and severely limits the usefulness of spectroscopy as a diagnostic tool.
- Atomic and Molecular Physics and Spectroscopy
- Rocket Engines