As the vibration reduction effect of the floating raft vibration isolation system is not good in the low-frequency range, in order to improve the vibration isolation performance of the floating raft vibration isolation system, the pneumatic butterfly valve is introduced into the floating raft system. The dynamic models of floating raft isolation system with dynamic pneumatic butterfly valve, self tuning damper and active self tuning damper are established respectively by using the substructure admittance synthesis method. Taking power flow as an index, the influence of vibration absorber on power flow transmission characteristics of floating raft system under single frequency excitation is studied. The floating raft vibration isolation device has good vibration and noise reduction performance, and is widely used in the vibration isolation of ship equipment. The floating raft vibration isolation device is usually equipped with multiple machines, so it is subject to multi frequency disturbance.
The traditional research on floating raft regards the floating raft as a rigid body, ignoring the influence of the elastic motion of the raft on the dynamic transmission characteristics of the system.
The vibration of the floating raft system includes not only the rigid body vibration of each subsystem, but also the elastic body vibration of the raft frame and foundation, as well as the rigid flexible coupling vibration of each subsystem. Therefore, the floating raft must be considered as a complex elastic coupling system. Since the vibration reduction effect of the floating raft vibration isolation system is not good in the low-frequency range, in order to improve the vibration isolation performance of the floating raft system, dynamic vibration absorbers, self tuning vibration absorbers and active self tuning vibration absorbers are introduced to suppress the low-frequency vibration of the floating raft vibration isolation system. The dynamic vibration absorber has good reliability, but its structural parameters are fixed and the effective vibration absorption frequency band is narrow. The self tuning vibration absorber is between the passive vibration absorber and the active vibration absorber. By changing its structural parameters, the vibration absorption frequency is kept consistent with the external excitation frequency of the main vibration system to achieve the ideal vibration absorption effect. It has both the reliability of the passive vibration absorber and the adaptability and high performance of the active vibration absorber. Whether the pneumatic butterfly valve is a vulnerable part depends on the normal road conditions. If the pneumatic butterfly valve moves with frequent bumps, it will stretch at a high frequency, and the oil temperature in the pneumatic butterfly valve will gradually rise, which is not conducive to the long-term use of the pneumatic butterfly valve.