New Considerations on Causes for Combustion Instability in Liquid Propellant Rockets

Abstract

The droplet vaporization, wake burning, and chemical kinetics processes are investigated theoretically with a view toward explanation of a mechanism which can cause combustion instability in liquid propellant rockets. Past research efforts and a new treatment of the unsteady vaporization process are drawn together lo provide a reasonably unified picture of unsteady mechanisms. It is shown that while vaporization can be an important contributor to chamber stability criteria, it cannot be the major supporting mechanism. Other processes are indicated which hold more promise for future research.