Abstract: Thrust bearing is one of the most important components which affect the coupled vibration of the shafting-hull coupled structure. Its impedance characteristics affect the transmission characteristics of the longitudinal oscillatory force from the propeller to the hull structure directly. So, the thrust bearing’s oil film stiffness in the ship propulsion system has a critical influence on the coupled vibration of the shafting-ship hull structure. The thrust bearing’s dynamic characteristics have been investigated in this paper and the thrust bearing’s oil film stiffness at different propulsion speeds is obtained, which is further applied to the dynamic model of the shafting-hull structure. The coupled vibration of the shafting-hull structure at different propulsion speeds is analyzed. The results show that the thrust bearing’s oil film stiffness at the low and medium propulsion speeds is the leading factor that affects the transmission of the longitudinal oscillatory force from the propeller to the hull structure, hence it must be considered in the prediction and control of the hull-structure’s vibration and acoustic radiation induced by the longitudinal oscillatory force.

Key words: vibration and wave, thrust bearing, oil film stiffness, structural vibration, acoustic radiation

摘要： 在轴系－艇体结构耦合系统中，推力轴承是轴系与艇体结构振动耦合的关键部件之一，其阻抗特性直接决定了纵向脉动力到艇体结构的传递特性，对系统的耦合振动有着至关重要的影响。对推力轴承的动力学特性进行研究，得到在螺旋桨不同转速下的推力轴承油膜刚度，并将其应用于轴系－艇体结构耦合系统的动力学模型中，进而对不同转速下的轴系－艇体结构耦合振动进行分析。结果表明，推力轴承油膜刚度在中低转速条件下是纵向脉动力向艇体结构传递的重要影响因素，因而对螺旋桨纵向脉动力诱导的艇体结构振动与声辐射的预报和控制必须对其加以考虑。

关键词: 振动与波, 推力轴承, 油膜刚度, 结构振动, 声辐射