RESEARCH STUDY OF LIGHT EMISSION CAUSED BY PRESSURE FLUCTUATIONS IN ROCKET ENGINES
Abstract
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.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1966
- Accession Number
- AD0632439
Entities
People
- B. Hornstein
- C. Budnik
- W. Courtney