RIASSUNTO
Abstract
In this study, the behavior of the coupled mooring system and floating body is analyzed. The related works are introduced for the mooring analysis of the floating body. The Equations motion are introduced for calculating mooring force connected with the floating body. For formulating equations of motion, the concept of the constrained force is applied for compact expression of it. The input and output data of the module for calculating mooring force is defined. The static analysis and quasi-static analysis are performed. For the analysis, equilibrium equation for elastic catenary mooring line is used by employing finite element method, and the C# solver is developed in this research. The analysis results are validated by comparing with other research results.
Introduction
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. The analysis of mooring line is performed using non-linear finite element method (FEM).