Our recent work has focused on developing a comprehensive stability algorithm that can be used as a diagnostic tool in the developmental stages of large combustors. The newly developed algorithm is based on the latest technological advances that suggest incorporating the effects of acoustical, thermal and vortical waves into the energy equation.
The new representation of chamber acoustics permits estimating the growth or decay of the system energy with most rotational flow effects accounted for. In the process, a generalized mean-flow description that mimics realistic chamber conditions is obtained. This representation enhances the accuracy of both linear and nonlinear stability equations used in industry. The improvements in acoustic energy gains also help to explain experimental findings that elude the present stability assessment methodology. Furthermore, our work explains the origins of several injection-driven instabilities observed in solid, liquid, and hybrid rocket tests. Our team is currently engaged in evaluating a generalized framework that encompasses the breadth of contributing factors to combustion instability that must be incorporated to fully quantify the stability characteristics in a rocket engine.
