Hydrodynamic Analysis of Lap Type Offshore Wind Turbine Installation Vessel

This paper mainly studies the transformation technology, kinematics and dynamics characteristics of a new offshore wind turbine installation ship. The transformation process is mainly for the semi-submersible barge, through the installation of "lap joint device" and jacket platform on the bow, and the deployment of anchor, ballast water and mooring cable on the stern, to ensure that the installation of offshore wind turbines meet the requirements of the specification. Research on kinematics and dynamics based on potential flow theory and establish frequency domain-time domain model of wind power installation ship by using hydrodynamic analysis software AQWA to verify the numerical model and provide test data for real sea state operation through peak response; finally, further analyze different influencing factors under the working sea area with AQWA, including exploring the kinematic and dynamic response of wind speed, wind wave current angle, wave period and other parameters to the working conditions. The results show that the lapping installation method is suitable for the installation of wind turbines due to its small amplitude of motion and dynamic response of the hull under the environmental conditions in the offshore waters of China. It also shows that this reform method has engineering application value. The response amplitude of the hull is less affected by the wind speed; the angle of wind, wave and current will have a greater impact on the response amplitude of the installation vessel, the amplitude in the direction of facing wave is smaller, while the amplitude in the direction of beam wave and following wave is larger; as the peak period of wave spectrum increases from 6 s to 10 s, the response amplitude becomes larger and larger. Beam waves and sea conditions with large periods shall be avoided as far as possible during engineering operations.