复合随机因素下航空发动机结构的可靠性分析

STRUCTURAL RELIABILITY ANALYSIS OF AN AEROENGINE WITH COMPLEX UNCERTAINTY

同时考虑航空发动机材料的随机性，结构几何形状的随机性，随机载荷和随机边界条件，研究复合随机因素下的概率有限元，在摄动法的基础上推导出结构的随机应力场，并建立相应的可靠性理论。分析随机因素的特征后，导出现有的航空发动机结构可靠性分析的各种计算方法，并进行了航空发动机的轮盘的可靠性分析。

Random meterial properties,geometrical shapes,forces and displacement boundary condition of an aeroengine are directly introduced into functional variational formulations and a unified random variational principle and the probabilistic finite element method with the small parameter perturbation method are provided.Based on second-order perturbation technique,the formulations for the random stresses and the reliability of the aeroengine′s structures are derived.According to analysis the characteristics of these random parameters,the simple methods for analyzing the aeroengine structural reliabilty are obtained.At last,the reliability of a rotating disk of the aeroengine is analyzed with a simple numerical example.