Analysis on ship free vibration characteristics

In order to analyze the global and local vibration characteristics for training ship of Shanghai Maritime University,the empirical formula method and finite element 3D modeling method are adopted to calculate vibration modal of the whole and superstructure of the ship in two kinds of typical cases.The results of these calculation shows that free vibration characteristic of the hull is good and the first-order frequency of superstructure part is close to the dangerous range of vibration.Based on the results,some recommendations are given for the superstructure design and future research.The study shows that the calculation model can be simplified by combining empirical formula method with finite element method.