Suppression of axial combustion instability in solid rocket motors

A numerical model for the prediction of undesirable axial combustion instability symptoms in solid-propellant rocket motors is utilized in the process of demonstrating various approaches for suppressing this instability behaviour. The unsteady interior one- or two-phase flow in the motor chamber, the oscillation of the surrounding structure of the propellant and motor casing, and the corresponding transient combustion process, are all incorporated within this comprehensive model. Example numerical results are presented for a cylindrical-grain motor having differing characteristics with respect to particle loading and grain geometry (fore and aft cross-sectional area changes), in illustrating the effectiveness of the particular suppression technique being applied.