Study on Hydrodynamic Forces and Safety of Huge Floating Body

为了充分利用海洋空间，浮式超大型近海结构物已成为当今人们关注的焦点。可以解决噪音、有限的土地空间和生态问题的浮动机场就是一个例子。为了实现这种超大型海上结构，必须准确评估其在海洋环境中的安全性和可靠性，包括在波浪中的性能。为此，必须准确了解风、浪、流等水动力外力，估算浮体的水弹性特性，并将其反馈到规划设计中。本研究以在巴西作业的涉油浮式海上结构为基础，针对大型海上结构的模具受力、水弹性响应、安全性、可靠性和姿态控制等问题进行研究。在本研究中，研究人员相互授权，海上结构的运行和实验的执行相互搜索。通过研究，可以了解柱间相互作用、姿态控制等水动力特性。在姿态控制方面，我们提出了气动执行机构。在作动器布置不均匀的情况下，通过模态组成表示弹性变形的数值模拟，得到了较好的控制效果。此外，采用7m长度模型进行模型试验，验证了姿态控制的可能性及其局限性。

For the utilization of ocean space, floating type very large offshore structures are taking into account today. A floating airport, which can resolve the problems of noise, limited land space and ecology, will be one example.In order to realize such kind of very large offshore structure, safety and reliability in ocean environment including behavior in waves must be evaluated accurately. For that purpose, hydrodynamic external forces like wind, waves and current must be known exactly and hydro elastic characteristics of the floating body must be estimated and feed backed to the planning and design. This research is aiming at the evaluation of die external forces, hydro elastic responses, safety, reliability and attitude control of very large offshore structure based on the oil related floating offshore structures operated in Brazil. For this research, researchers are delegated each other, and operation of offshore structures and execution of experiments are searched each other. From the research, we could know the characteristics of hydrodynamic forces like interaction between columns and attitude control. About attitude control, we proposed pneumatic actuator. For the case of non-uniform actuator arrangement, the optimal control could give relatively good results by carrying out numerical simulation expressing elastic deformation by modal composition. Furthermore, the possibility of attitude control and its limitation were examined by carrying out model test using 7m length model.