中文摘要：

针对某水下航行器的燃烧室，用有限元的方法对隔板抑制燃烧不稳定性的声学机理进行了初步研究。利用ANSYS软件数值计算了隔板长度变化以及隔板数目变化时，对应的燃烧室声模态，并比较了它们的变化对燃烧室声模态造成的影响。计算表明：隔板抑制燃烧不稳定主要是通过对燃烧室腔体的声学共振频率进行平移，避开了与其相耦合的频率，从而达到抑制燃烧不稳定的目的。同时随着隔板长度的增加，靠近隔板处的声腔部分的切向声模态轴向化会逐步加剧，这样就可以得到更好的抑制作用。

英文摘要：

Using finite element method （ FEM）, we studied the acoustic mechanism of restraining the combustion in stability with baffles in the combustion chamber of a marine engine. Acoustic modes of the combustion chamber were calculated with FEM software ANSYS when the length and number of baffles change, and the influences of the changes on the acoustic modes are compared. Calculation results show that the restraining of combustion instability by baffles is mainly through the modification of the oscillation frequency of the combustion chamber so that it is not coupled with the combustion process of the propellant, and that increasing the length of the baffle will improve the restraining effect.