The wave observation buoy system is widely used in wave measurement for exploiting marine oil and gas resources, in which the mooring line is one of the most critical components. At present, the design and analysis for the mooring line mainly relies on quasi-static analysis with a large dynamic magnification factor based on the engineering experience instead of dynamic analysis, resulting in high computational efficiency but inaccurate dynamic response prediction. Therefore, it is of significance to validate the deviation between quasi-static analysis and dynamic analysis for ensuring sufficient design safety. This paper carries out a series of quasi-static analysis and dynamic analysis for the mooring line of a disc-shaped wave observation buoy in regular waves. Through comparing the maximum mooring tension in the two analysis methods, it is found out that the dynamic magnification factor is related to the water depth, chain diameter, mooring length, and wave conditions. Eventually, the recommended value of dynamic magnification factor under different occasions is obtained to provide guidelines for engineering designers.
The prerequisite of developing and utilizing the tremendous ocean resources is to accurately grasp the atmospheric and oceanographic data, such as the wind velocity, current profile, wave characteristics of sea areas. These hydrometeorological data is of great significance to maritime activities. At present, one of the most reliable, effective, and important means in marine observation is based on the ocean data buoy with various measuring sensors in its substructure. Take measuring wave height and period as an example, the wave observation buoy, one kind of ocean data buoy, can provide long-term, high-precision, and real-time wave parameters through the satellite correspondence in various complex marine environments. With the rapid development in last eighty years, the ocean data buoy can be divided into disc-shaped buoy, cylindrical buoy, spherical buoy, and ship-shaped buoy according to the shape of its substructure. Among them the disc-shaped buoy is widely deployed in global sea areas because of its large effective space, superior stability, and pleasant wave following performance. Typically, the substructure diameter of the disc-shaped buoy is as large as 12~15 m and as small as 1~3 m.
