基于动力吸振器的中空轴系纵向减振研究
Investigation on Longitudinal Vibration of Hollow Shaft Based on Dynamic Vibration Absorber

针对中空轴系的纵向振动，在轴系内部安置阻尼动力吸振器对其进行了减振设计。结合子结构综合法和传递矩阵法建立了附加阻尼动力吸振器复杂轴系的动力学模型，分析了阻尼动力吸振器与轴系的耦合系统在简谐激励下的动力学响应，并采用了有限元仿真，表明阻尼动力吸振器的加入使得轴系的纵向共振峰得到抑制，轴系共振频率附近的频响曲线趋于平缓。试验结果表明，附加阻尼动力吸振器后的轴系一阶纵向共振峰值下降显著，阻尼动力吸振器对轴系的纵向减振具有显著的效果。在中空轴系内部空间安装吸振器，既不占用多余的空间，又能获得较好的减振效果，可以作为船舶推进轴系纵向减振的一种新选择。
With the increasing size of ship, the damage of the longitudinal vibration of shaft is increasingly exposed. This paper adopted a damping vibration absorber to attenuate longitudinal vibration of the hollow shaft system, established the dynamic model of shaft with dynamic vibration absorber combining with the substructure synthetic method and transfer matrix method, and analyzed the frequency response function of shaft under harmonic excitation, which is verified by the traditional finite element method using ANSYS software. The theoretical calculation and simulation results showed that the frequency response function curve near the resonance frequency turned to smooth by adding dynamic vibration absorber. A dynamic vibration absorber is designed and then an experimental verification is conducted. The testing results show that the resonance peak is strongly attenuated when dynamic vibration absorber attached to the shaft, which indicates the attenuation effect of dynamic vibration absorber is obvious. Based on hollow characteristics of a large marine propulsion shafting system, a DVA can be installed into the void location of the hollow shafting, which saves space and has a good absorption performance, can be a new choice in the control of longitudinal vibration of marine propulsion shafting system in future.