航空发动机叶片/机匣碰摩不对称热效应和升温曲线研究-中国材料进展

文章信息/Info

Title:: Asymmetric Thermal Effect and Temperature Rise Curve of Blade/Case Rub-Impact of Aero-Engine

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

Keywords:: blade; case; rubbing; asymmetric thermal effect; temperature rise curve

摘要:: 基于有限元模拟对航空发动机压气机叶片与机匣碰摩过程中的摩擦热效应和温度变化进行了研究。研究发现，在单次碰摩过程中，叶尖截面小，热流密度大，温度高；机匣面积大，热流密度小，温度低；叶尖与机匣的碰摩热效应存在不对称现象。在转子旋转一周内，每个叶片只受到一次碰摩，而机匣要受到多个叶尖的碰摩，因此，在转子旋转一周之内，叶片与机匣的碰摩热效应同样存在不对称现象。这种多次不对称热效应使得叶尖与机匣温度分布与变化规律呈现出明显差异，叶尖的升温只发生在碰摩过程中，在不接触的剩余时间内由于空气的对流换热，叶尖温度持续降低；对于机匣，在与叶尖碰摩过程中，机匣温度上升，在与相邻两个叶尖碰摩的间隙时间内则通过空气对流换热进行降温，因此，机匣的升温曲线具有明显的波动增加的变化规律。

Abstract:: Based on finite element simulation, the friction-heating effect and temperature variations during rub-impact between blade and casing of rotor were studied. During a single rub-impact process, the asymmetric thermal effect exists due to the radiant area difference of the blade and the case. During a cycle of blade rotation, there is also an asymmetric thermal effect during the process due to different rubbing times of the blade and the case. This multiple asymmetric thermal effect makes the temperature distribution and change curve of the blade tip and the case appear distinct. The temperature rise of the blade only occurs in the process of rub-impact, and the temperature of the blade continues to decrease due to the convective heat transfer of air in the remaining time. However, the temperature of the case increases slowly because the case rubs with different blades, and the temperature drops during the interval time of the casing rubbing with two adjacent blade tips. Therefore, the temperature rise curve of the case increases in a fluctuating manner.