考虑轴承动刚度的船舶集成减振系统纵向传递特性研究

Research on longitudinal transmission characteristics of marine integrated vibration isolation system considering thrust bearing dynamic stiffness

运用传递矩阵法建立推力轴承边界条件改变后的轴系纵振模型,以试验室轴系台架参数为算例,开展推力轴承集成减振系统低频动态传递特性仿真分析和实船推力轴承纵向动刚度测试,重点讨论集成减振系统设计参数对传递特性的影响规律,结果表明:集成减振系统能有效衰减螺旋桨叶频和1倍频引起的推力轴承纵向低频振动,质量设计参数应大于轴系5倍以上,刚度设计参数优先考虑气囊固有频率,实船推力轴承纵向动刚度数值处在8E8~3E9N/m范围内,且主要影响二阶纵振固有频率,对20~70 Hz低频范围内减振效果影响较小。

The longitudinal vibration model of the shafting after the boundary conditions of the thrust bearing are changed is established by using the transfer matrix method.Taking the parameters of the shafting bench in the laboratory as an example,the simulation analysis of the low-frequency dynamic transmission characteristics of the integrated damping system of the thrust bearing and the longitudinal dynamic stiffness test of the real ship thrust bearing are carried out,and the influence of the design parameters of the integrated damping system on the transmission characteristics is emphatically discussed.The results show that the integrated damping system can effectively attenuate the longitudinal low-frequency vibration of the thrust bearing caused by the propeller blade frequency and the first harmonic frequency.The mass design parameters should be more than 5 times larger than the shafting.The stiffness design parameters give priority to the natural frequency of the airbag.The longitudinal dynamic stiffness of the thrust bearing of the real ship is in the range of 8Es~3E'N/m,and mainly affects the natural frequency of the second-order longitudinal vibration,with little impact on the damping effect in the low-frequency range of 20~70 Hz.