航空发动机叶盘结构应力和变形的概率分析

为了更准确地描述航空发动机叶盘结构的变形以及控制的合理性,提出了1种高效、高精度的概率分析方法,即极值响应面法(ERSM,Extremum Response Surface Method),在分析中考虑了典型载荷(如热载荷和离心载荷)的动态性和边界条件的非线性等因素,合理地选取输入变量且考虑了参数的随机性和不确定性等,通过确定性分析得到叶盘结构的总变形和应力分布随时间的变化规律,同时找到其变形最大点作为概率分析的输入目标。通过科学合理的概率分析,不仅获得了其可靠度、拟合样本、样本直方图、极值响应面和累计概率分布函数并且对其应力分布和总变形进行灵敏度分析,得到了叶盘结构变形和应力分布的主要影响因素,同时给出了应力与总变形的相关性。最后,将ERSM与Response Surface Method(RSM)和Monte Carlo(MC)法进行比较分析,验证了ERSM在航空发动机叶盘结构分析中的有效性。

Probability Analysis of Structure Stress and Deformation for Aeroengine Bladed Disk

By describing the reasonability of structure deformation and control for aeroengine bladed disk,a highly efficient and precise method of probability analysis called ERSM（Extremum Response Surface Method）was proposed.The classic loading＇s dynamics and nonlinear factors on boundary conditions were considered,selecting the input variant and considering the parameters＇ random and uncertainty.The changing rules of deformation and stress for bladed disk were obtained with time,and the largest deformation and stress node points of bladed disk was found.Not only its reliability,historical sample,extreme response surface and the cumulative probability distribution function were obtained,its sensitivity of stress distribution and total deformation was analyzed,the main effect factors of structure deformation and stress distribution were obtained,but also the relativity of stress total deformation was presented.Finally,ERSM is verified to be effective in the blade disk by comparatively analyzing ERSM,RSM and MC.