The laying of submarine pipelines is a crucial aspect of marine oil and gas resource development.Traditional towed methods struggle to adapt to the variability of ocean depths and complex environments.In response to Acergy's proposal for a wave towing method in the Girassol project,this study analyzes its application in the laying of a 2.0 km-long seabed pipeline.Firstly,considering the characteristics of deep-sea marine environments,a numerical model for pipeline towing is established using the concentrated mass method.Mechanical calculations for the pipeline,tow cable,and floatation devices,as well as hydrodynamic load calculations,are introduced.Secondly,a modeling of the towing process using the nonlinear finite element software OrcaFlex is conducted to simulate the actual project's towing process.Next,the dynamic mechanical performance variations of the pipeline and tow cable are explored by comparing two towing methods:single-wave and double-wave towing under similar conditions.Finally,sensitivity analysis is performed on factors such as buoyancy-to-weight ratio,towing speed,tow cable length and sag angle,as well as current velocity and direction.The results indicate that the wave towing method effectively reduces the tension demand on the tow cable during construction but may increase local bending and stress response of the pipeline.Compared to single-wave towing,double-wave towing shows advantages in mitigating local damage effects caused by variations in towing speed and is better suited to different water depths.The influence of complex ocean current conditions on the mechanical performance of the pipeline during towing is significant,emphasizing the importance of selecting appropriate laying windows before construction to prevent pipeline damage.
关键词
海底管道/波浪式拖管法/管道铺设/集中质量法/拖航参数/海洋油气开采
Key words
submarine pipeline/wave towing method/pipeline laying/concentrated mass method/towing parameters/marine oil and gas extraction
维普
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