航空发动机叶片/机匣碰摩超瞬态行为建模方法-中国材料进展

文章信息/Info

Title:: A Modeling Method for Ultra-Transient Behavior of Aero-Engine Blade/Case Rub-Impact

Author(s):: DONG Yu; LIU Meijun; YANG Guanjun; (State Key Laboratory for Mechanical Behavior of Materials, School of Materials Science and Engineering, Xi‘an Jiaotong University, Xi’an 710049, China)

摘要:: 为了分析航空发动机叶片/机匣碰摩过程中的超瞬态摩擦热效应，基于有限元方法建立了叶片/机匣碰摩模型，研究了单次碰摩条件下界面的微区超瞬态摩擦热效应，并对模拟过程中空间尺寸与时间步长对模拟结果的影响进行探究分析。研究发现，由于叶片与机匣摩擦速度快、碰摩时间短，只在叶尖很小的范围内发生超瞬态传热，产生的摩擦热以分子量级进行传递。叶片/机匣碰摩模型建立过程中，网格尺寸划分过大、时间步长取值过大，会导致模拟结果不能真实反应碰摩过程的微区超瞬态热效应。为此，通过对建模过程中模型空间尺寸与时间步长的优化，得到了能够准确反映温度微区超瞬态特性的建模方法，阐明了网格尺寸与时间步长匹配对微区超瞬态行为的影响规律，为叶片-机匣碰摩模型的建立奠定了基础。

Abstract:: To analyze the blade/case rub-friction process of aero-engine, a blade/case rub-friction model is established based on the finite element method, and the ultratransient friction heat effect at the interface under a single rub is studied. The influence of grid size and time step on simulation results during rub-impact simulation is explored and analyzed. It is found that the ultra-transient heat transfer occurs only in a small range of blade tip due to the high friction speed and short rubbing time between blade and casing. At the same time, the friction heat generated by rubbing is transferred by the order of molecular size in space dimension. During model building, grid size and time step have a significant influence on simulation results. Therefore, by optimizing the grid size and time step in the modeling process, a correct modeling method that can accurately reflect the ultra-transient characteristics of the temperature micro-zone is obtained. The influence of grid size matching with time step on micro-zone super-transient behavior is clarified, which establishes the foundation for the model of blade-case rub-impact friction.