Design and Vibration Suppression Performance of a

To address the need for high-efficiency vibration isolation in marine rotary pump units, this paper proposes a coupled isolation system that integrates vibration isolators and flexible connectors, and systematically investigates its vibration suppression performance. By combining experimental parameterized modeling with full-scale test platform validation, an efficient analytical framework capable of accurately predicting the system’s broadband vibration isolation performance has been established. This framework provides a reference for engineering design that balances model reliability and practical applicability. The study first obtained the transfer complex stiffness of the isolators through mechanical impedance experiments and, combined with the stiffness parameters of the flexible connectors measured by an MTS testing machine, established a nonlinear spring-damper equivalent model for the isolators and flexible connectors. A three-dimensional finite element model of the rotary pump unit coupled isolation system was developed using the explicit dynamics method, and the vibration transmission characteristics of the coupled isolation system under complex excitation from the rotary pump were analyzed using the vibration acceleration level difference between the “machine foot” and “foundation” as the evaluation index. To verify the reliability of the model, a full-scale rotary pump unit isolation test platform was constructed, and multi-condition vibration tests were conducted. The results show that the finite element model of the coupled isolation system can effectively predict the vibration response, with the overall vibration level error between numerical calculations and experiments within ±3 dB. Under various operating conditions involving changes in rotational speed and water pressure, the system demonstrates good broadband isolation performance, with the maximum vibration acceleration level difference reaching 29.32 dB.