采用模型试验方法，研究了雷诺数为2．5×10^3～2×10^4范围内张力腿平台的涡激运动问题。试验中设计了一套考虑水平和垂向系泊刚度的锚泊方案，捕捉到涡激运动中的“锁定”和“两支”等现象；试验结果表明：横流向和顺流向均...采用模型试验方法，研究了雷诺数为2．5×10^3～2×10^4范围内张力腿平台的涡激运动问题。试验中设计了一套考虑水平和垂向系泊刚度的锚泊方案，捕捉到涡激运动中的“锁定”和“两支”等现象；试验结果表明：横流向和顺流向均发生了频率锁定现象，横向达到锁定范围的折合速度为 Ur ＝4．0～7．0，顺流向为 Ur ＝6．0～7．0，且横向运动居主导地位；在 Ur≤4．0的非锁定区，涡激升力模型满足斯特哈尔关系；而当 Ur ＞4．0时，该公式不再适用。试验结果也表明：流向角是影响平台运动轨迹的关键因素，当流向角为0°时，平台运动呈正“8字形”；15°时，运动轨迹为“香蕉形”；45°时，为略向左侧弯曲的扁“8字形”。展开更多
A numerical simulation and an experimental study on vortex-induced motion（VIM） of a new type of deep draft multi-columns floating drilling production, storage and offloading（FDPSO） are presented in this paper. The...A numerical simulation and an experimental study on vortex-induced motion（VIM） of a new type of deep draft multi-columns floating drilling production, storage and offloading（FDPSO） are presented in this paper. The main dimension, the special variable cross-section column and the cabin arrangement of the octagonal pontoon are introduced based on the result. The numerical simulation is adapted to study the effects of current incidence angles and reduced velocities on this platform’s sway motion response. The 300 m water depth equivalent truncated mooring system is adopted for the model tests. The model tests are carried out to check the reliability of numerical simulation. The results consist of surge, sway and yaw motions, as well as motion trajectories. The maximum sway amplitudes for different types of offshore platform is also studied. The main results show that the peak frequencies of sway motion under different current incidence angles and reduced velocities vary around the natural frequency. The analysis result of flow field indicates that the change of distribution of vortex in vertical presents significant influences on the VIM of platform. The trend of sway amplitude ratio curve of this new type FDPSO differs from the other types of platform. Under 45° current incidence angle, the sway amplitude of this new type of FDPSO is much smaller than those of other types of offshore platform at 4.4 ≤ V;≤ 8.9. The typical ‘8’ shape trajectory does not appear in the platform’s motion trajectories.展开更多
文摘采用模型试验方法，研究了雷诺数为2．5×10^3～2×10^4范围内张力腿平台的涡激运动问题。试验中设计了一套考虑水平和垂向系泊刚度的锚泊方案，捕捉到涡激运动中的“锁定”和“两支”等现象；试验结果表明：横流向和顺流向均发生了频率锁定现象，横向达到锁定范围的折合速度为 Ur ＝4．0～7．0，顺流向为 Ur ＝6．0～7．0，且横向运动居主导地位；在 Ur≤4．0的非锁定区，涡激升力模型满足斯特哈尔关系；而当 Ur ＞4．0时，该公式不再适用。试验结果也表明：流向角是影响平台运动轨迹的关键因素，当流向角为0°时，平台运动呈正“8字形”；15°时，运动轨迹为“香蕉形”；45°时，为略向左侧弯曲的扁“8字形”。
基金financially supported by the National Natural Science Foundation of China(Grant No.51779109)the Natural Science Foundation of Jiangsu Province(Grant No.BK20171306)
文摘A numerical simulation and an experimental study on vortex-induced motion（VIM） of a new type of deep draft multi-columns floating drilling production, storage and offloading（FDPSO） are presented in this paper. The main dimension, the special variable cross-section column and the cabin arrangement of the octagonal pontoon are introduced based on the result. The numerical simulation is adapted to study the effects of current incidence angles and reduced velocities on this platform’s sway motion response. The 300 m water depth equivalent truncated mooring system is adopted for the model tests. The model tests are carried out to check the reliability of numerical simulation. The results consist of surge, sway and yaw motions, as well as motion trajectories. The maximum sway amplitudes for different types of offshore platform is also studied. The main results show that the peak frequencies of sway motion under different current incidence angles and reduced velocities vary around the natural frequency. The analysis result of flow field indicates that the change of distribution of vortex in vertical presents significant influences on the VIM of platform. The trend of sway amplitude ratio curve of this new type FDPSO differs from the other types of platform. Under 45° current incidence angle, the sway amplitude of this new type of FDPSO is much smaller than those of other types of offshore platform at 4.4 ≤ V;≤ 8.9. The typical ‘8’ shape trajectory does not appear in the platform’s motion trajectories.
