The vibration dissipation mechanism of the rotating blade with a dovetail joint is studied in this paper. Dry friction damping plays an indispensable role in the direction of vibration reduction. The vibration level is reduced by consuming the total energy of the turbine blade with the dry friction device on the blade-root in the paper. The mechanism of the vibration reduction is revealed by the variation of the friction force and the energy dissipation ratio of dry friction. In this paper, the flexible blade with a dovetail interface feature is discretized by using the spatial beam element based on the finite element theory. Then the classical Coulomb-spring friction model is introduced to obtain the dry friction model on the contact interfaces of the tenon-mortise structure. What is more, the effects of the system parameters (such as the rotating speed, the friction coefficient, the installation angle of the tenon) and the excitation level on blade damping characteristics are discussed, respectively. The results show that the variation of the system parameters leads to a significant change of damping characteristics of the blade. The variation of the tangential stiffness and the position of the external excitation will affect the nonlinear characteristics and vibration damping characteristics.

研究了带燕尾榫接头的旋转叶片的振动消散机理。干式摩擦阻尼在减振方向上起着不可或缺的作用。通过消耗带有干式摩擦装置的涡轮叶片在纸根上的总能量来降低振动水平。通过摩擦力和干摩擦的能量耗散率的变化揭示了减振的机理。本文基于有限元理论，利用空间梁单元离散了具有燕尾形界面特征的柔性叶片。然后引入经典的库仑弹簧摩擦模型，得到榫榫结构接触面的干摩擦模型。更，分别讨论了系统参数（如转速，摩擦系数，榫的安装角度）和激励水平对叶片阻尼特性的影响。结果表明，系统参数的变化导致叶片阻尼特性的显着变化。切向刚度和外部激励位置的变化将影响非线性特性和减振特性。