基于Donnell-Mushtari理论的燃烧室机匣模态特性研究

Research on Modal Characteristics of Combustion Chamber Casing Based on Donnell-Mushtari Theory

基于经典的Donnell-Mushtari薄壳理论公式,推导了航空发动机燃烧室机匣在一定边界条件下的固有频率计算公式。利用多组波数建立了固有频率随周向波数n的变化规律。最后搭建了物理实验平台,将理论解与实验测试进行了对比分析,误差在10%左右。结果验证了理论计算方法的有效性,为后期燃烧室机匣减振工艺及工装设计提供了理论计算依据。

Based on the classic Donnell-Mushtari thin-shell theory formula,the natural frequency calculation formula of the combustor casing under certain boundary conditions is deduced.Using multiple sets of wavenumbers,the law of natural frequency changing with circumferential wave number n is established.Finally,a physical experiment platform is built,and the theoretical solution is compared with the experimental test,and the error is about 10%.The results verify the effectiveness of the theoretical calculation method and provide a theoretical calculation basis for the later combustion chamber casing vibration damping process and tooling design.