基于连续体旋转梁模型的碰摩故障动力学特性分析  

Dynamic characteristics of a continuous rotating beam model with a rubbing fault

作　　者：太兴宇[1] 马辉[1] 谭祯[1] 闻邦椿[1] 

机构地区：[1]东北大学机械工程与自动化学院,沈阳110819

出　　处：《振动与冲击》2013年第18期43-48,共6页Journal of Vibration and Shock

基　　金：国家科技支撑计划项目(2009BAG12A01-F01-3);中央高校基本科研业务费专项资金资助项目(N100403008);中央高校基本科研业务费专项资金资助(N120603001);教育部新世纪人才支持计划(NCET-11-0078)

摘　　要：针对弹性叶片与刚性机匣的碰摩故障,以直板叶片为研究对象,将叶片简化为考虑旋转的悬臂梁模型,并据哈密顿原理及变分方程推导出悬臂叶片的解析模型。再据叶盘与机匣的偏心关系,推导出叶尖与机匣的间隙变化函数,判定碰摩是否发生。考虑离心刚化、旋转软化及科氏力影响,采用Newmark-β显式数值积分算法,对单叶片-机匣碰摩进行数值仿真。结果发现,由于科氏力的存在,使叶片轴向位移与横向位移间发生耦合,碰摩力消失后,轴向位移会以弯曲动频做自由振动;高转速时,横向位移对轴向位移影响减弱,而弯曲方向振动则随机性较大。Aiming at a rubbing fault between a flexible blade and a rigid casing, taking a bar blade as a studying object, the blade was simplified as a rotating cantilever beam model. In addition, its analytic model was deduced using Hamilton＇s principle and a variational equation. According to the decentration relation between a disc and a casing, the clearance changing function between a blade tip and a casing was derived, it was used to figure out if a rubbing occurs. Considering the effect of centrifugal rigidization, spinning softening and Coriotis force, the numerical simulation of a bladecasing rubbing was performed by using Newmark-β explicit numerical integral algorithm. The results showed that due to Coriolis force, the coupling occurs between the blade＇s axial displacement and its transverse displacement; after the rubbing force disappears, the free vibration frequency of the blade＇s axial displacement is its bending dynamic one ; at high rotating speed, the influence of the blade＇s transverse displacement on its axial displacement is weakened, and the randomness of the blade＇s bending vibration becomes larger.

关 键 词：叶片 悬臂梁 碰摩故障 动力学特性 科氏力 

分 类 号：TK4[动力工程及工程热物理—动力机械及工程]