Study on Local Vibration Control of the 100 m X-BOW Polar Exploration Cruise Ship

Abstract

A finite element model of a 100 m X-BOW polar exploration cruise ship has been developed. The ship’s frequency response analysis was conducted, with the simulated results closely matching the test data. The maximum discrepancy was 22%, equating to a negligible 0.24 mm/s difference in terms of comfort. This indicates that the simulation meets the standards of engineering precision and validates the model’s accuracy. Utilizing a global modal equivalent mass solution approach, in conjunction with the spatial distribution of local modal mass, a method for calculating the equivalent mass of a single local mode in mixed modes has been devised. This method was applied to determine the equivalent mass of the local vibration region of the 100 m X-BOW ship. Tuned mass dampers (TMDs) were then designed based on this equivalent mass. Analysis reveals that the TMDs achieve a 31 dB vibration absorption effect at a frequency of 13.4 Hz with a mass ratio of 0.05. They also provide a control effect at 10 Hz and 18.8 Hz, corresponding to 3 dB and 2 dB reductions, respectively. The control frequency band is broad, flat, and robust, indicating the effectiveness of the TMDs in mitigating vibrations across a wide range of frequencies.

Keywords

• polar exploration cruise
• frequency response analysis
• modal equivalent mass
• tuned mass dampers
• mass ratio