SEAKEEPING TEST OF THE TAIDAFLOAT OFFSHORE FLOATING PLATFORM
Journal
Journal of Taiwan Society of Naval Architects and Marine Engineers
Journal Volume
42
Journal Issue
3
Date Issued
2023-01-01
Author(s)
Abstract
The free decay and seakeeping model tests of the TaidaFloat offshore semi-submersible floating platform with a mooring system were conducted in this study. The weights of the wind turbine and tower were distributed uniformly among the three column supports. Free decay tests of six degrees of freedom, including surge, sway, heave, roll, pitch, and yaw, were conducted. The natural frequencies and damping ratios were derived from the free decay tests. The damping ratios of the six degrees of freedom are approximately linear with the initial velocity. Response amplitude operators of six degrees of freedom were obtained from the seakeeping tests. Seakeeping involves testing for surge, sway, and yaw cannot be conducted by the wavemaker when the wave frequency falls below 0.3Hz. The RAO of surge, sway, and heave increases as the wave frequency de-creases, according to the seakeeping test results. The surge RAO has a local maximum value at a non-dimensional frequency of 1.4, which is induced by pitch motion. The roll RAO increases as the frequency decreases, and it continues to increase as the frequency decreases further. It may be due to the unbalanced forces of the mooring lines in the long-wave conditions. The pitch RAO has a maximum value at the natural frequency, and there is a local maximum value at a non-dimensional frequency of 0.8, which is near the natural frequency of heave. The yaw RAO increases as the frequency of the wave decreases, which is a normal trend.
Subjects
Damping Ratio | Floating Offshore Wind Platform | Free Decay | Natural Frequency | Response Amplitude Operator | Seakeeping Performance
Type
journal article