In this study, the behavior of the coupled mooring system and floating multibody body is analyzed. The equations of motions for multibody and mooring line are introduced. To formulate combined equations of motion, the concept of the constrained force is applied. The combined equations of motion are compact, and it is easy to manipulate. The input and output data of the module for calculating mooring force is defined. The static analysis, quasi-static analysis and dynamic analysis were performed. For development of this simulator, C# language is used in this research. The analysis results are validated by comparing with other research results.
Needs for accurate analysis of dynamic behavior have been increasing in many engineering fields, including the shipbuilding industry. There are several simulation tool which is focused on the traditional mechanical systems, such as car and machinery. In general, however, shipbuilding and offshore industry is different from conventional mechanical system in aspect of their purpose, size, and shape. Therefore, there are some limits to apply analysis tools, which are developed for conventional mechanical system, to the shipbuilding and offshore industry. Fig. 1 shows several kinds of the offshore operations in shipbuilding industry.
Due to these reasons, simulation tools are developed in several researches for the dynamic analysis of the shipbuilding and offshore operation process (Ku et al., 2014, Roh et al., 2014). The simulation programs developed from these researches can deal with multibody system, so that more accurate dynamic analysis can be completed.
These programs define the mooring line as a linear spring, and the spring constants are determined with some assumption and linearization. However, in some offshore operation, such as installation and decommissioning, mooring analysis can be one of the most important analysis point. Therefore, this paper presents about dynamic analysis for the moored floating multibody system. Dynamic analysis of mooring line is performed using non-linear finite element method(FEM).
