• CN:11-2187/TH
  • ISSN:0577-6686

机械工程学报 ›› 2019, Vol. 55 ›› Issue (13): 102-112.doi: 10.3901/JME.2019.13.102

• 特邀专栏:航空发动机健康监测与故障诊断 • 上一篇    下一篇

一种用于航空发动机热端部件三维裂纹行为分析的数值方法

刘鹤1, 杨晓光1,2, 石多奇1,2   

  1. 1. 北京航天航天大学能源与动力工程学院 北京 100191;
    2. 北京航天航天大学先进航空发动机协同创新中心 北京 100191
  • 收稿日期:2018-07-11 修回日期:2018-12-24 出版日期:2019-07-05 发布日期:2019-07-05
  • 通讯作者: 杨晓光(通信作者),男,1962年出生,博士,教授,博士研究生导师。主要研究方向为高温结构强度及材料的疲劳与断裂、本构理论及疲劳寿命预测等。E-mail:yxg@buaa.edu.cn
  • 作者简介:刘鹤,男,1990年出生,博士研究生。主要研究方向为高温结构强度及材料的疲劳与断裂。E-mail:liu_he@outlook.com
  • 基金资助:
    国家重点基础研究发展计划(973计划,2015CB057401)和国家自然科学基金(S1775019)资助项目。

A Numerical Approach to Investigate 3D Crack Behavior on Aeroengine Hot-end Components

LIU He1, YANG Xiaoguang1,2, SHI Duoqi1,2   

  1. 1. School of Energy and Power Engineering, Beihang University, Beijing 100191;
    2. Collaborative Innovation Center of Advanced Aero-engine, Beihang University, Beijing 100191
  • Received:2018-07-11 Revised:2018-12-24 Online:2019-07-05 Published:2019-07-05

摘要: 裂纹在航空发动机热端部件服役过程中不可避免,裂纹行为的准确预测对于服役安全和寿命管理具有重要意义,针对热端部件上三维裂纹行为特征的研究有着巨大需求。面向航空发动机热端部件结构,对复杂几何和应力状态下的三维裂纹的理论从数值应用方面进行了系统总结,并对数值分析中应用的关键技术进行了研究。通过对各型裂纹应力强度因子分量的求解,并选择恰当的裂纹扩展方向准则,实现了复杂的三维复合型裂纹行为的模拟。裂纹尖端单元类型的选取将会影响计算结果的精度,通过对奇异性单元特征尺寸的控制保证了三维裂纹参量求解的准确性。为了获取模拟过程中裂纹前沿曲线的演化,应用"逐个点"的节点增量法作为更新策略重构裂纹前沿,同时裂纹尖端的三层单元环结构的使用保证了网格的稳定更新。通过对比表面裂纹的解析法和数值计算结果,验证了该方法对裂纹驱动力参量的求解精度。最后以高压涡轮叶片为实例,通过数值模拟计算得到了涡轮叶片不同位置裂纹扩展的规律。

关键词: 复合型裂纹, 航空发动机热端部件, 节点增量法, 裂纹前沿曲线重构, 奇异性单元特征尺寸, 三维裂纹, 数值方法

Abstract: Cracks are inevitable during the service of aeroengine hot-end components. The accurate prediction of crack behaviour is of great significance for service safety and life management, thus there is a great demand for research on the behaviour of three-dimensional cracks on hot end components. Focusing on the structure of the aero-engine hot-end components, the three-dimensional crack theories under complex geometry and stress conditions are systematically summarized from numerical application, and the key technologies employed in numerical analysis are studied. By solving the stress intensity factor components of mixed-mode cracks and selecting the appropriate crack growth path criterion, the complicated three-dimensional crack behaviour is simulated. The type of element around crack tip affect the accuracy of the calculation, and the accuracy of the three-dimensional crack parameter solution is ensured by controlling the feature size of the singular element. In order to obtain the evolution of the crack front curve in the simulation, the "point-by-point" node increment method is used as an updating strategy to reconstruct the new crack front. At the same time, the use of a three-layer element ring structure around crack tip ensures a stable remesh. By comparing the analytical method of surface cracks and numerical results, the accuracy of the method to solve the crack driving force parameters is verified. Finally, using the high pressure turbine blade as an example, the law of crack propagation at different positions of the turbine blade is obtained by numerical simulation.

Key words: 3D crack, aeroengine hot-end components, characteristic size of singularity element, crack front remodeling, mixed-mode crack, node increment method, numerical approach

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