Internal solitary wave-induced sediment resuspension and offshore infrastructure loading

内部孤立波引起的沉积物再悬浮和海上基础设施负荷

• 批准号: RGPIN-2017-04568
• 负责人: Boegman, Leon
• 金额: $ 2.99万
• 依托单位: Queen's University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=645696
• 关键词: Internal; solitary; wave; induced; sediment

Internal solitary waves are ubiquitous features of the coastal ocean. Propagating on subsurface density interfaces, these waves have ~1 km wavelengths, ~100 m amplitudes and >1 m s-1 currents; thereby transporting significant energy shoreward from their offshore generation sites. Where the internal solitary waves shoal, the associated near-bed turbulence re-suspends and re-distributes bottom sediment, pumping organic matter, nutrients and contaminants vertically through the water-column. The suspended sediment creates nepheloid (turbidity) layers that are 100s of m thick and forms immense dune fields with ~100 m wavelengths on the ocean floor. Internal solitary waves also apply hazardous loads to subsea infrastructure, with wave impacts leading to broken drill strings and anchor chains, lost remote operated vehicles and listing of rigs, causing millions of dollars in repositioning costs and lost revenue. Moreover, present subsea pipeline design criteria require costly secondary stabilization and increased pipeline wall thickness in solitary wave breaking zones. Reduced uncertainty in estimation of the associated design criteria will save $10s of millions.******The proposed research will train 4 PhD, 6 MSc and 5 undergraduate students, who will perform laboratory experiments and numerical simulations to investigate internal solitary wave shoaling in the coastal ocean. They will: (1) develop models to parameterize the dynamic effects of internal solitary waves on sediment resuspension and quantify the associated sediment transport; (2) determine whether bottom roughness is preventing high-resolution computer simulations from reproducing laboratory-generated solitary waves; (3) measure the design loads (force, torque and stress) applied by internal solitary waves to offshore oil and gas infrastructure (vertical columns and horizontal pipelines).******This research will develop solutions to address critical needs of (1) Oceanographers, who require laboratory data to predict wave resuspension and breaking locations in the field; (2) Numerical Modellers, who require laboratory data for model validation; (3) Government Agencies that manage fisheries, navigation and develop building codes; (4) aspiring MetOcean engineers, who require advanced graduate training to work in the oceanography and resource sectors; and (5) Resource and Engineering Companies that manage rigs and lay pipeline in internal solitary wave impacted waters, using costly secondary stabilization and conservative pipeline wall thicknesses.

内部孤独波是沿海海洋的无处不在特征。 在地下密度界面传播，这些波的波长约为1 km，幅度约为100 m和> 1 m s-1电流。从而从其离岸一代地点运送大量的能源岸。 在内部孤立的波浪浅滩的地方，相关的近床湍流重新悬浮并重新分发底部沉积物，泵送有机物，营养物质和污染物，并垂直通过水柱。 悬浮的沉积物会产生100s厚的肾上腺素（浊度）层，并形成巨大的沙丘田，海底的波长约为100 m。 内部孤独波还将危险负荷施加在海底基础设施中，波浪撞击导致钻孔和锚定链，损失的远程操作车辆和钻机上市，从而导致数百万美元的重新定位成本和损失的收入。 此外，目前的海底管道设计标准需要昂贵的次要稳定，并增加了孤立波动区域的管道壁厚。估计相关设计标准的不确定性降低将节省100亿美元。******拟议的研究将培训4博士学位，6个MSC和5名本科生，他们将进行实验室实验和数值模拟，以调查沿海海洋中内部单独的波浪鞋。 他们将：（1）开发模型，以参数化内部孤立波对沉积物重悬的动态影响并量化相关的沉积物传输； （2）确定底部粗糙度是否阻止了高分辨率的计算机模拟再现实验室生成的孤立波； （3）测量由内部孤立波施加的设计负载（力，扭矩和压力），用于近海油气基础设施（垂直柱和水平管道）。 （2）数字模块，他们需要实验室数据进行模型验证； （3）管理渔业，导航和开发建筑法规的政府机构； （4）有抱负的Metocean工程师，他们需要高级研究生培训才能在海洋学和资源领域工作； （5）使用昂贵的次要稳定和保守的管道壁厚厚度，在内部孤立波浪中管理钻机和铺设管道的资源和工程公司。