火焰筒热疲劳分析与寿命估计  

THERMAL FATIGUE ANALYSIS AND LIFE PREDICTION OF COMBUSTOR LINER

作　　者：耿小亮[1] 郭运强[1] 张克实[1] 秦亮[1] 

机构地区：[1]西北工业大学工程力学系,西安710072

出　　处：《机械强度》2007年第2期305-309,共5页Journal of Mechanical Strength

基　　金：航空科学基金(04C53027);西北工业大学青年创新基金(M016202)资助~~

摘　　要：发动机火焰筒的热疲劳损伤是导致火焰筒失效的主要原因。在火焰筒温度急剧变化过程中,结构上存在温升滞后现象,热冲击载荷造成局部高温区压缩塑性变形;在持续升温与停车降温过程中,结构自身约束导致此处形成拉伸应力,引发循环塑性行为,从而产生疲劳裂纹。基于该机理,采用有限元方法模拟不均匀温升和循环过程及应力应变的变化,并结合Coffin-Manson规律对火焰筒寿命进行预测,与实际情况对比,说明该机理的合理性。Failure of combustor liners is generally produced by thermal fatigue damage. During sharply instantaneous change of temperature of the liner, there is a delay of temperature rise in the structure, and then the compressive plastic deformation at the local high temperature zones is engendered by thermal shock loading. During the continuous rising and falling of temperature by starting up and shutting down, cycles of tensile and compressive stresses are formed at these local zones and the cycles that arouse plastic damage accu- mulation will lead to the initiation of cracks. In this investigation, finite element method was applied to simulate the thermal cycle procedure and the response of stress-strain cycles. As a result, the life of the liner was calculated by using Coffin-Manson equation and the simulation appears reasonable in comparison with the experimental data.

关 键 词：火焰简 热疲劳 瞬态传热 裂纹 

分 类 号：V231.95[航空宇航科学与技术—航空宇航推进理论与工程] O346[理学—固体力学]