横摇条件下主机隔振对船舶推进轴系横向振动的影响研究

Impact of main engine vibration isolation on marine propulsion shafting transverse vibration under lateral rolling

以典型船舶轴系试验台架为研究对象,基于有限元法,建立了该轴系的有限元模型,并通过试验对模型进行了验证,计算分析了主机隔振条件下轴系的固有特性,并从运动形式的角度出发,将横摇运动等效为重力加速度的变化,作为边界条件,对该模型进行瞬态响应分析。计算结果表明:主机隔振会降低整个系统的固有频率,但对轴段的固有特性没有影响;在横摇条件下,联轴器位置的传递力和位移显著增大,并传递至轴段部分,使轴系的振动更加严重。

A typical marine shafting test bench was investigated in this paper. A finite element model of the shafting was established based on FEM and verified by tests. Natural characteristics of the shafting with main engine vibration isolation were analyzed. Lateral rolling was treated as equivalent variational acceleration of gravity. It was applied to the FEM model for the transient response analysis as boundary conditions. The computation results indicate that main engine vibration isolation reduces the natural frequencies of the whole system but makes no difference to those of shafting. Transfer forces and displacements at coupling increase and transmit to shafting,causing much stronger vibration of shafting.