潜艇艉轴及电机激振对电机基座加速度的影响

电机振动为潜艇噪声的重要振源，掌握其特性对于优化艇体结构设计有着重要的意义。采用结构有限元耦合流体边界元的附加质量阻尼算法，对潜艇的2种不同位置激振的工况进行水下振动计算，并对数值计算结果进行了比较和分析。从离散频率的加速度值和功率两个层面上初步讨论了低频段内艉轴激振力与电机激振力对电机基座上加速度的影响。结果表明：在艉轴激振力比电机激振力大一个数量级的情况下，艉轴激振力对电机基座加速度的影响远小于电机激振力对其的影响，因而可以忽略。在实艇航行中，当艉轴与电机激振力同时存在的情况下，确保了电机振动特征信号测量的准确性。

Analysis of the Acceleration Effects on Submarine's Engine Pedestal Produced by the Excitation Force from Propeller Shafts and Engines

The engine vibration is a major excitation source of submarine noise and requires substantial consideration during the structural design process. In this paper, an approach combining the finite element method with the boundary element method is proposed to calculate the underwater vibration of submarines with two different excitation sources - the propeller shaft and the engine. The acceleration effects on the submarine＇s engine pedestal, produced by the low frequency excitation force from the two sources mentioned above were also investigated. The obtained numerical results were compared and analyzed at different frequencies and power values. It was seen that the acceleration effects produced by the propeller shaft was quite small and could be safely neglected when the propeller shaft excitation was one order greater in magnitude than the engine vibration force. Overall, this observation could simplify and benefit the measurement of engine vibration characteristics in actual submarine applications.