轴系校中状态对艉轴承力传递特性影响

船舶轴系的弯曲振动通过艉轴承传递到船体引发船体艉部振动并产生噪声,是影响船舶舒适性和安全性的主要因素之一。船舶轴系由于较大的自重和出于对轴承保护的原因必须进行轴系校中,校中过程中轴承垂向位置的变化将会改变各轴承所受载荷,继而改变轴承刚度,影响轴系振动特性及轴承处的力传递特性。为此,利用传递矩阵法建立轴系校中和弯曲振动模型,对一轴系实例分别进行直线校中和以艉轴后轴承静载最小为目标的优化校中,求得两种不同校中状态下各轴承处受力响应,研究发现两种校中方式低频段相差微小,在高频段有明显区别。

Effect of Shaft Alignment on Stern-bearingForce Transmission Characteristics

The transmitting of ship shaft lateral vibration to the ship body through stern bearings will induce the vibration of ship stern and noise, which is the major factor for ride comfort and safety. Ship shaft alignment must be conducted because of its own heavy weight and protection for bearings. The load of every bearing will be changed with the change of bearing height in the process of shaft alignment, which will also change the bearing stiffness and influence the shaft vibration characteristic and bearing transmitting force. In order to solve this problem, shaft alignment and lateral vibration are modeled by the transfer matrix method. According to a shaft example, line alignment and optimal alignment of minimum rear bearing static load are conducted respectively. The result shows: the bearing force responses of these two methods are narrowly different in the low frequency band, but have an obvious difference in high frequency band.