弹性支承对船舶轴系的影响分析

船舶推进轴系引起的船体振动问题日益突出,为了减小推进轴系传递给船体的振动,从改变振动传递路径的角度提出一种轴系整体弹性支撑方案。建立有限元模型,改变支撑平台结构刚性和隔振器刚度分别计算轴承基座间相对位移和轴承载荷。所选取的平台方案中,在重力下轴承基座间最大相对位移为1.216 mm。推力作用下当推力大于500 kN时,采用1阶弯曲频率在18.2 Hz及以上的平台方案时,轴承基座间最大相对位移小于0.3 mm,隔振器刚度变化则对轴承载荷影响不大。通过调整平台刚度和隔振器刚度,可以将弹性支撑系统对轴系影响控制在标准范围内,保证轴系安全运行。

Analysis of the influence of elastic mounting on marine propulsion shaft

The hull vibration caused by ship propulsion shafting is becoming more and more serious.To reduce the vibration of the propulsion shafting to the hull,an overall elastic support scheme of shafting is proposed with changing the vibration transmission path.Establishing the finite element model calculate relative displacement of bearing pedestals and bearing load by changing the rigidity of supporting platform and vibration isolator.The maximum relative displacement is 1.216 mm under gravity in all selected platform schemes.When the thrust is greater than 500 kN under the action of thrust,The maximum relative displacement less than 0.3 mm in the platform scheme thats’first order bending frequency greater than 18.2 Hz.The change in vibration isolator stiffness has no obvious diffierence on bearing load.The influence of elastic support system on shafting can be controlled within the standard range to ensure the safe operation of shafting by adjusting platform stiffness and vibration isolator stiffness.