운동량 플럭스 비의 변화에 따른 기체 중심 스월 동축형 분사기의 기체 가진 동특성 연구

Abstract

Abstract Combustion instability is critical problem in developing liquid rocket engine. There have been many efforts to solve thisproblem. In this study, the method was sought through the injector as part of these efforts to suppress combustion instability.If the injector can suppress the disturbance coming from the supply line as a kind of buffer it will serve to reduce combus-tion instability. Especially we target at gas propellant oscillation in gas-centered swirl coaxial injector. The phenomenon issimulated with acoustic excitation of speaker. The film thickness response at injector exit was measured by using a liquidfilm electrode. Also the response of spray to the disturbance was observed by high-speed photography. Gas-liquid momentumflux ratio and the frequency of feeding gas oscillation were changed to investigate the effect of these experimental parame-ters. The trend of response by varying these parameters and the cause of weak points was studied to suggest the better designof injector for suppressing combustion instability.