LIQUID ROCKET ENGINE COMBUSTION INSTABILITY STUDIES
Abstract
Various combustion problems related to high frequency instability in liquid rocket engines were studied. Using the steady-state and instability computer programs developed under this study, a parametric investigation was conducted. This investigation determined the influence of droplet radius, droplet distribution, injection velocity, chamber pressure, and mixture ratio on the minimum threshold disturbance required to trigger combustion instability in a Transtage type engine configuration. The propellant combination considered was monomethylhydrazine/nitrogen tetroxide. Results of the study show that increases in injection velocity and droplet distribution increased stability. An increase in chamber pressure, based on constant flow rate increased stability while increases in chamber pressure, at a constant contraction ratio, decreased stability. There appears to be a droplet size for minimum stability, with changes in either direction resulting in improved stability. Results also show that due to the vapor phase reactions, monomethylhydrazine/nitrogen tetroxide vaporize at approximately the same rate. Thus, the oxidizer or fuel could be made to control the combustion process by slight changes in the injector and engine parameters. For the engine configuration studied the oxidizer vaporized slower than the fuel.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1966
- Accession Number
- AD0487242
Entities
People
- B. P. Breen
- C. F. Sanders
- M. R. Beltran
- R. J. Hoffman
- T. C. Kosvic