施加轴向力的旋转轮盘低循环疲劳试验

为满足配装某型飞机的发动机在外场使用的需要,利用传统安全寿命法对航空发动机轮盘进行了低循环疲劳试验.通过有限元方法计算轮盘在发动机工作条件下的应力状态,结合失效分析,确定了轮盘的关键部位和相应的标准循环.针对该轮盘的应力状态受轴向力影响大的特点,运用类比法确定了试验参数,设计的试验装置实现了在旋转条件下对轮盘施加轴向力.研究表明:轮盘关键部位的确定不仅与应力水平有关,还与结构和失效模式有关.试验设计须考虑轴向力对轮盘应力状态产生的影响.试验装置通过调节油量控制轴向力,可同时满足不同试验参数的新盘和外场使用盘的需要.

Low cycle fatigue test of rotating disc under axial loading

In order to meet the outfield service requirement of the engine assembled in a aircraft, the research was conducted on low cycle fatigue test of aero-engine disc based on traditional safety life method. The stress state of disc under engine working conditions was calculated using finite element method, while the critical positions and the corresponding standard cycle were confirmed with failure analysis. According to the feature that the disc's stress state was affected by axial loading, the test parameters were confirmed through analogy, and the test rig was designed to apply axial loading to the disc under rotating condition. The research shows: the critical position of the disc is not only related to stress level, but also depends on structure and failure mode. Test design needs to consider the impact on the stress state by axial loading. By adjusting the amount of oil, the test rig can control the axial loading and meet the requirement of various tests with different parameters for the new disc and the used one after outfield service.