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Objectives The resonance changer （RC） is designed under rigid boundary condition and then applied to the elastic coupling boundary condition. This paper explores the influence of changes in boundary conditions on RC parameter design and its vibration reduction effect.Methods Considering the characteristics of the shafting rotor, a dynamic model of a shafting-hull coupling system with a RC is established. Based on the transfer matrix method, the vibration and force transfer characteristics of the system are analyzed. The structural parameters of the RC are designed according to the shafting longitudinal vibration characteristics under rigid boundary conditions, then applied to the hull.Results The results show the feasibility of the above parameter design and application scheme. The influence of the anti-resonance vibration isolation mechanism on the system can be divided into the stiffness region, anti-resonance region and mass region. Through sensitivity analysis, it is proposed that the structural parameters of the RC are adjustable.Conclusions The results of this study can provide valuable references for the application of RC to full-sized ships.

Balanced fiber-reinforced rubber (FRR) pipes not only provide displacement compensation when transporting pressurized media but also prevent additional forces and displacements from being exerted on the connected pipeline system. Investigating the balanced performance of FRR pipes and the axial stiffness of balanced pipes is crucial for optimizing pipeline design and improving the reliability of pipeline systems. This paper develops a numerical model of FRR pipes that considers the nonlinearity of the rubber material and the interaction between the rubber matrix and fiber-reinforced layers. Using this model, the balanced performance of the pipe is calculated, and its axial stiffness under combined internal pressure and axial load is analyzed. Numerical results are compared with experimental data for validation. The results indicate that the pipe's balance is achieved through the combined effects of the elongation and rotation of the reinforcing fibers and the deformation of the rubber matrix, highlighting the significant impact of the rubber matrix on the mechanical performance of the FRR pipe. Furthermore, the pipe's balanced performance and axial stiffness are highly sensitive to the winding angle of reinforcing fibers. The proposed numerical model fills the gap in using numerical methods to evaluate the balanced performance of FRR pipes and provides valuable insights for their design and optimization. [ABSTRACT FROM AUTHOR]