考虑间隙影响的涡旋压缩机转子系统动态特性研究

Study on the dynamic characteristics of scroll compressor rotor system considering the influence of clearance

针对运动副间隙对涡旋压缩机传动系统运行特性的影响问题,基于非线性弹簧阻尼模型和库仑摩擦力模型建立其运动副间隙接触碰撞模型,运用多体动力学理论分析不同间隙条件下曲柄销受力及驱动轴承角加速度等的变化规律,使用有限元方法进一步分析转子系统在不同角加速度激励下的瞬态动力响应。结果表明:间隙对转子系统的位移、角速度、角加速度的影响程度依次增加,并随着间隙的增大呈现高幅值低频率的现象;曲轴所受应力随间隙的增加而增大,曲柄销与驱动轴承的接触刚度随着间隙的增大而减小,使曲轴临界转速降低,增加了转子发生共振的危险。

In view of the influence of the joint clearance on the operating characteristics of the scroll compressor transmission system,based on the non-linear spring damping model and Coulomb friction model,the contact collision model with joint clearance was established.The multi-body dynamics theory was used to analyze the changing law of the crank pin and the angular acceleration of the driving bearing under different clearance conditions,and the finite element method was used to further analyze the transient dynamic response of the rotor system under excitation of different angular accelerations.The results show that the influence of the clearance on the displacement,angular velocity and angular acceleration of the rotor system gradually increases,and as the clearance increases,the phenomenon of high amplitude and low frequency appears.The stress on the crankshaft rises with the increase of the clearance,and the contact stiffness between the crank pin and the drive bearing decreases with the increase of the clearance,which reduces the critical speed of the crankshaft and increases the risk of rotor resonance.