连接刚度对船舶减振支架振动疲劳寿命的影响

Influence of connector stiffness on vibration fatigue life of vibration damping bracket in ship

当船舶动力设备受到各种交变载荷的作用时,易导致其支撑结构发生振动,从而失效甚至破坏.但目前对船舶减振支架结构的振动疲劳和弹性体刚度对其影响的研究较少.文中建立了船舶减振支架的有限元分析模型,对其进行模态分析和频率响应分析,然后基于功率谱密度法对该支架结构进行了振动疲劳分析.通过改变连接齿轮箱与支架的弹性体刚度,来分析其对减振支架结构振动疲劳寿命的影响.由分析可知,连接齿轮箱与支架的弹性体刚度对船舶减振支架结构的振动疲劳寿命有较大影响,并得出了支架刚度与寿命之间的关系,为更加合理可靠地进行结构振动疲劳寿命分析提供了相关理论依据.

When ship power equipment is subjected to various alternating loads,their supporting structures are prone to vibrate distinctly,leading to being invalid or being destroyed sometimes.Currently,researches concerning about the vibration fatigue of vibration damping bracket in ship and the effect of the elastic stiffness on its fatigue life are in shortage.First of all,the finite element model of the bracket is established in this paper,then the analyses of modal and frequency response are carried on and the vibration fatigue life is analyzed on the basis of the power spectral density method.Finally,the effect of stiffness on the vibration fatigue life is analyzed with different elastic stiffness of the elastomers connecting the gearbox and the bracket.The results show that the connector stiffness has significant influence on the vibration fatigue life,and the relations between the connector stiffness and the life of the bracket are obtained.This study provides theoretical basis for life analysis of vibration fatigue.