Ship and Offshore Floating Platform Motions in Extreme Seas

极端海洋中的船舶和海上浮动平台运动

• 批准号: RGPIN-2014-03714
• 负责人: Qiu, Wei
• 金额: $ 1.75万
• 依托单位: Memorial University of Newfoundland
• 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=662771
• 关键词: Ship; Offshore; Floating; Platform; Motions

The objective of the proposed research is to develop numerical methods to compute motions of ships and offshore platforms in extreme seas. **With the oil and gas development in deepwater, floating systems for exploration, production and drilling are becoming increasingly important. While the offshore floating structures provide the only safe and cost effective means for the location and extraction of hydrocarbons from the sea bottom, they are likely to encounter all the extreme conditions that occur at their locations. Ships also often encounter extreme waves in their routes. The prediction of responses of ships and offshore floating structures in extreme seas is of vital importance to their safe and efficient operations. **In extreme seas, ships and offshore structures can experience highly nonlinear phenomena such as green water, slamming and wave run-ups, which involve free-surface breaking and multi-phase flows. The associated loads can cause local and global structural damages. Although great progress has been made in solving the nonlinear ship motion problems with potential-flow based methods, there are great difficulties in treating highly distorted or breaking free surfaces. With the advance of high performance computers, these difficulties can be overcome by the computational fluid dynamics (CFD) methods based on solving the Navier-Stokes equations. The proposed research will focus on the development of a CFD method for predicting ship and offshore platform motions in extreme seas. The research is summarized as follows: (1) A constrained interpolation profile (CIP)-based finite difference method will be further developed to compute the near-field flows and motions of ships and platforms considering multi-phase flow and breaking free surfaces; (2) Since CFD methods generally have limited capability for simulating the waves in the far field, a potential-flow based Rankine method will be coupled with the CIP method to take the far-field wave effect into account; (3) Validation studies will be carried out for various ships and platforms. Model tests will also be conducted for a ship model in extreme waves. The experimental results and other published data will be used to validate the numerical tool. **Through the proposed research, highly qualified personnel in the area of marine hydrodynamics with strong computational skills will be trained. The proposed research will contribute nationally and internationally to the field of ship and offshore hydrodynamics, especially the numerical studies of large-amplitude ship motions in extreme seas and breaking free surfaces.

拟议研究的目的是开发数值方法来计算极端海洋中船舶和海上平台的运动。 **随着深海石油和天然气的开发，用于勘探、生产和钻井的浮动系统变得越来越重要。虽然海上浮式结构为从海底定位和提取碳氢化合物提供了唯一安全且具有成本效益的手段，但它们很可能会遇到其所在位置发生的所有极端条件。船舶在航线上也经常遇到极端的波浪。船舶和海上浮动结构在极端海洋中的响应预测对其安全高效运行至关重要。 **在极端海洋中，船舶和海上结构可能会经历高度非线性现象，例如绿水、撞击和波浪爬升，其中涉及自由表面破裂和多相流。相关载荷可能会导致局部和整体结构损坏。尽管基于势流的方法在解决非线性船舶运动问题方面取得了很大进展，但在处理高度扭曲或破裂的自由表面方面仍存在很大困难。随着高性能计算机的进步，这些困难可以通过基于求解纳维-斯托克斯方程的计算流体动力学（CFD）方法来克服。拟议的研究将重点开发用于预测极端海洋中船舶和海上平台运动的 CFD 方法。研究工作总结如下：（1）进一步发展基于约束插值轮廓（CIP）的有限差分方法来计算考虑多相流和破碎自由表面的船舶和平台的近场流动和运动； (2) 由于CFD方法对远场波浪的模拟能力普遍有限，因此将基于势流的朗肯方法与CIP方法结合以考虑远场波浪效应； （3）针对各类船舶和平台开展验证研究。还将对船模进行极端波浪下的模型试验。实验结果和其他已发表的数据将用于验证数值工具。 **通过拟议的研究，将培训具有强大计算技能的海洋流体动力学领域的高素质人才。拟议的研究将为国内外船舶和近海流体动力学领域做出贡献，特别是极端海洋和破碎自由液面中大幅度船舶运动的数值研究。