Numerical Analysis And Experimental Research On Hydroelastic Response Of The Very Large Floating Structure

The21st century is the century of ocean, the vast ocean contains rich marine resources. In recent years, with the development and improvement in marine science and technology, the exploitation of ocean has gradually covered ocean oil and gas industry, ocean chemical industry and some new and promising industry area. Speeding up the development of the ocean economy with efficient exploration and exploitation of the marine resources has a tremendous impact on our national economy. Facing the current situation, it is necessary for us to enhance the research and design on very large floating structures(VLFS).The key factor of the design of VLFS is the analysis of the hydrodynamic characteristics, Traditional marine floating structures are considered as rigid body, which neglects the impact of fluid and applies rigid body theory when deal with the dynamic problems. Different from traditional floating structures, VLFS are a kind of very flat floating structures with large flexibility and the elastic deformation is even more important than the rigid motion and cannot be ignored. The interaction between VLFS and fluid is very complicated structure-fluid interaction problem. the motion of VLFS changes the fluid field and the fluid in turn leads to the elastic deformation of the VLFS. In order to tackle this interaction problem, VLFS and fluid need to be coupled with the theory of hydroelasticity. Based on the two-dimensional potential theory, the theory of hydroelasticity is applied to forecast the hydroelastic responses of the VLFS.The interaction system between VLFS and fluid is symmetric and the system is divided into three parts. Before calculating the potential of the fluid field, eigenfunction expansion-matching method is applied to calculate the symmetric potential and the asymmetric potential of the fluid field. Using the thin plate theory to deduce the motion equation of the VLFS before calculate the hydroelastic responses of the VLFS. A model experiment is conducted to justify the analytical results. Twenty one displacement sensor are applied in the experiment to get the displacement of the VLFS. The comparisons between the analytical results with foreign experimental results and the experimental results in the thesis justifies the theory in the thesis. The impact of several environmental factors on the hydroelastic responses of the VLFS is analyzed and a comparison among three different modal functions is made, which provides reference for latter research.