Numerical Simulation of Ocean Environmental Change Due to Very Large Offshore Structures in a Bay

海湾超大型近海结构引起的海洋环境变化的数值模拟

• 批准号: 05302057
• 负责人: KYOZUKA Yusaku
• 金额: $ 5.06万
• 依托单位: KYUSHU UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Co-operative Research (A)
• 财政年份: 1993
• 资助国家: 日本
• 起止时间: 1993 至 1994
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-05302057/
• 关键词: HUGE OFFSHORE STRUCTURE; OFFSHORE AIRPORT; TIDAL SIMULATION; DIFFUSION CALCULATION; ENVIRONMENTAL ASSESSMENT; POSITIONING CONTROL SYSTEM; MULTIPLE CONNECTED BODY; WAVE DRIFTING FORCE; 海洋環境; 潮流解析; 多重連帯浮体; 波漂流力; 相互干渉理論; 海洋環境変化; 汚染物質の拡散

Fundamental studies on ocean environmental changes due to a huge offshore structure are carried out in this project. An offshore airport in Ariake Bay is taken as an example and tidal simulations are conducted in the bay with/without the offshore airport. The deffusion simulations of COD from rivers are also conducted and the results of COD density patterns are compared. In tidal simulations, the moving effects of water on the tidal marsh are taken into account by the quasi-stastic approximation. In 1993, three location of a reclaimed airport and a simplified floating airport are compared in assessment functions which are defined by the area affected in tidal level and current velocity by the construction of the airport. The location of the airport is found to be very important in the tidal currents and deffusion of COD in the bay. In 1994, a new numerical program is developed for a pontoon type floating airport. Results of a floating airport show that it gives less effects on ocean en … More vironmental changes than reclaimed airports.A dynamic positioning system of a mooed floating platform is studied. Mooring is used to maintain the position of a floating platform against quasi-constant external forces induced by current and wind, and thrusters control slow drift oscillation. The LQI (Linear Quadratic with Integral) control system was adopted to prevent this oscillation.Simulations of motions in irregulay waves, currents and wind were carried out and the performance of LQI control system was presented.The wave drifting forces acting on a very large floating structure consisting of multiple barge type modules is studied theoretically and experimentally. The wave drifting forces on the multiple floating structure are estimated for two module connectors, a rotationally-hinge connector and a rotationlly-rigid connector. The effects of connector conditions and the number of bodies on wave drifting forces are presented graphically.A new method for computation of the hydrodynamic forces acting on a floating body in a harbor of arbitrary geometry is developed. The method is composed of the finite element method (FEM) for solving the harbor response and the boundary element method (BEM) for the floating body response. Some numerical results are presented for a barge in a rectangular harbor. Less

本项目开展了大型近海构筑物引起的海洋环境变化的基础研究。以有明湾某近海机场为例，对有无近海机场的海湾进行了潮汐模拟。本文还对河流中COD的扩散进行了模拟，并对模拟结果进行了比较。在潮汐模拟中，采用准静态近似法考虑了水对潮汐沼泽的移动效应。在1993年，我们比较了一个填海机场和一个简化的浮动机场的三个位置的评估功能，这些评估功能是根据机场建设对潮位和流速的影响来定义的。机场的位置对海湾内的潮流和COD扩散有重要影响。1994年，开发了一种新的浮桥式浮动机场的数值计算程序。研究结果表明，水上机场对海洋环境的影响比填海机场小，对环境的影响比填海机场大。研究了移动浮式平台的动态定位系统。系泊用于维持浮动平台的位置，以抵抗由电流和风引起的准恒定外力，推力器控制缓慢漂移振荡。采用LQI（线性二次积分）控制系统来防止这种振荡。进行了在不规则波浪、水流和风中的运动仿真，并介绍了LQI控制系统的性能。本文从理论和实验两方面研究了由多个驳船型模块组成的超大型浮式结构的波浪漂移力。对两种模块连接器——旋转铰链连接器和旋转刚性连接器——在多浮结构上的波浪漂移力进行了估计。用图形表示了接头条件和体数对波浪漂移力的影响。提出了一种计算任意几何形状港口浮体水动力的新方法。该方法由求解港口响应的有限元法和求解浮体响应的边界元法组成。给出了矩形港内驳船的数值计算结果。少

项目成果

M.NAKAMURA and W.KOTERAYAMA: "APPLCATION OF DYNAMIC POSITIONING SYSTEM TO A MOORED FLOATING PLATFORM" PROC.4TH INT.OFFSHORE AND POLAR ENG.CONF.VOL.1. 190-197 (1994)

M.NAKAMURA 和 W.KOTERAYAMA：“动态定位系统在系泊浮动平台上的应用”PROC.4TH INT.OFFSHORE and POLAR ENG.CONF.VOL.1。

M.Takaki and Y.Tango: "Wave Drifting Forces on Multiple Connected Floating Structures." Proc.Int.Conf.Hydroelasticity in Marine Technology. 403-415 (1994)

M.Takaki 和 Y.Tango：“多个相连浮动结构上的波浪漂移力”。

経塚 雄策、横山 和豊: "内湾の大規模海洋構造物が周辺海域に及ぼす海況変化について" 第12回 海洋工学シンポジウム. 485-492 (1994)

Yusaku Kyozuka，Kazutoyo Yokoyama：“关于周围海域内湾大型海洋结构引起的海况变化”第12届海洋工程研讨会485-492（1994）。

Y.Kyozuka and K.Yokoyama: "Ocean Environmental Change Due to an Offshore Airport in Ariake Bay" Techno-Ocean'94 Int.Symp.Proc.Vol.1. 69-74 (1994)

Y.Kyozuka 和 K.Yokoyama：“有明湾近海机场导致的海洋环境变化”Techno-Ocean94 Int.Symp.Proc.Vol.1。

K.KYOZUKA and K.YOKOYAMA: "OCEAN ENVIRONMENTAL CHANGE DUE TO AN OFFSHORE AIRPORT IN ARIAKE BAY" TECHNO-OCEAN'94 INT.SYMP.PROC.VOL.1. 69-74 (1994)

K.KYOZUKA 和 K.YOKOYAMA：“有明湾近海机场导致的海洋环境变化”TECHNO-OCEAN94 INT.SYMP.PROC.VOL.1。