Analysis of Hydrodynamic Characteristics and Dynamic Response of a New Type of Single Point Mooring Suspended Current Power Generation Device

Abstract

Based on the potential flow theory, this paper studies the hydrodynamic performance of a single point mooring suspended current power generation device by using the hydrodynamic software AQWA, and obtains the frequency-domain characteristic curves of the RAOs (Amplitude Response Operators) of each degree of freedom under the conditions of different wave direction angles and different height of gravity center. According to the results of frequency-domain analysis, considering the loads of wave and current, the time-domain coupling analysis of this single point mooring suspended current power generation device under the given sea condition is carried out, and the motion response of the system in irregular waves and the change of mooring line tension are studied. The results show that the peak value of the RAOs of surge and pitch first decreases and then increases with the increase of the wave angle. When the wave angle is small, there will be a large surge and pitch motion; the yaw motion mainly shows the low frequency resonance with the wave. The small variation of the height of the center of gravity can reduce the roll motion, but the influence is small. In a given sea condition, the single point mooring system can keep the current power generation device stable, but the RAO of yaw is large, which may affect the performance of the Savonius blade. The safety factor of mooring line is large, which can ensure the safety and reliability of power generation device.