Stability rating tests for the length-optimization of baffles in a liquid propellant combustion chamber using a pulse gun

Stability rating tests using a pulse gun, one type of artificial disturbance device, have been performed to optimize and to limit the axial baffle length of a combustor. To determine whether the combustor is stable when it is exposed to strong external perturbations or pressure oscillations, the decay time and amplitude ratio have been analyzed to quantify the stabilization capacity of the combustor. A baffle not big enough to cover the flame zone considered as the collision plane of the F-O-O-F impinging injector was not able to suppress external perturbations sufficiently. The combustion stability boundary limit of the present combustor can be determined with respect to the axial baffle length.