Optimzation design of resonance changer for marine propulsion shafting in longitudinal vibration

  Objectives  The transmission path of the longitudinal vibration of propeller shafting can be changed and the base response attenuated via a Resonance Changer(RC)integrated in the thrust bearing, enabling the natural frequency of the shafting to be avoided by the propeller's blade frequency and multiplier frequency excitation force. In this way, the purposes of vibration reduction and frequency adjustment can be achieved.

  Methods  In this paper, the mechanical model of longitudinal vibration of propeller shafting is established and the vibration model of the propeller shaft system is calculated on the basis of the transfer matrix method. The influence of the main parameters of the RC on the vibration isolation effect of propeller shafting is analyzed by taking the force transmission rate as the index. The methods of the minimization of maximum value and parameter correction of the curve area are used to optimize the main parameters of the RC.

  Results  The results show that the vibration isolation effect of propeller shafting is significantly improved when the RC is installed, and the vibration reduction effect of the RC can be improved by using the design method of the parameter correction of the curve area.

  Conclusions  The rational design of the RC's parameters can produce a vibration isolating system with excellent vibration isolation effects.