Basic Instability Mechanisms in Chemically Reacting Subsonic and Supersonic Flows
Abstract
Stability of one-dimensional piston-supported detonation was examined both numerically and analytically. Numerical calculations were conducted for a one-step, first-order, irreversible reaction obeying an Arrhenius rate expression. An approximate linearized stability theory was also developed for the case of high activation-energy reactions and the mechanism of instability identified. Analysis demonstrates that interaction between the irreversible temperature fluctuations and the reaction zone induces an oscillatory energy- source field, which then leads to shock perturbations and thereby the temperature fluctuation. Frequencies of all the unstable and stable modes of this system can be predicted. They agree remarkably well with the findings of the numerical calculations and the observations in blunt-body flow experiments. The problem of direct initiation of gaseous detonations was examined theoretically, to determine the correlation between the critical energy and power for successful initiation, and to predict their respective threshold values. Results were found to agree well with the experimental observations of cylindrical detonations in oxy-acetylene mixtures. (edc)
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1980
- Accession Number
- ADA215032
Entities
People
- G. E. Abouseif
- T. Y. Toong
Organizations
- Massachusetts Institute of Technology