海洋恶劣风环境下深海平台上层高耸结构风致动力效应分析及其数值模拟和试验研究

For the fulfillment of the national strategic demand for the exploitation of sea oil & gas, oriented by the objective of wind resistance design and disaster reduction of the high-rising truss tower structures stood upon deep sea platforms, which are highly sensitive to wind actions, the investigation on the interaction between high-rising truss tower structures stood upon the deep sea platform system and extremely sea environmental wind actions are carried out in this proposal, by using theoretical analysis and numerical/experimental simulations with introducing the sea wind data records. The scientific issues of the present proposal are focused on the research of the multi-scale wind-induced effects and its mechanism of the wind-sensitive truss tower structures and the analysis of dynamic wind action under sea environment. The key aspects include the following: studing/revealing the spatiotemporal traits, the characteristics oriented to engineering application and wind power spectrums of wind field near the sea surface, based on the sea wind/typhoon historical data records; investigating the advanced wind simulation technique based on the power spectrum, constituting a three dimensional time series model of the strong wind/typhoon applicable for engineering computation with high efficiency and high accuracy; establishing a refined multi-scale mechanical model and its modification, as well as the governing equation of the non-linear structural vibrations for high-rising truss tower structures stood upon deep sea platforms; proposing a identification tactic for the structural wind sensitivity and a refined time-frequency identification method for the structural dynamic responses, and revealing the key wind-induced effect and the dynamic time-dependent behaviors of the high-rising truss tower structures; realizing the physical simulation of the wind field near water surface in sea water pond/channel laboratory and performing a wind tunnel experiment investigation of structural modelling of high-rising truss tower. In brief, this research is expected to provide theoretical and technical supports for the wind-resistance safety design for high-rising truss tower structures stood upon deep sea platforms under sea wind environment.

面向海洋油气开发重大需求，以深海平台高耸风敏感结构抗风减灾和安全性为目标导向，以东海南海为背景，采用理论分析、数值计算、模型实验、实测数据运用等方法，开展海洋恶劣风环境下深海平台上层高耸结构风效应分析及其数值模拟与物理试验研究。科学问题紧扣深海平台风敏感结构多尺度关键风效应机理和海洋恶劣风环境作用。研究内容旨在揭示基于强/台风实测数据的近海面风环境时空特性和工程应用特征，提出强/台风风功率谱；建立风模拟方法，提出快速高精、工程适用的强/台风三维风时程模型；提出深海平台高耸塔架多尺度建模方法，建立精细化多尺度力学模型与模型修正及非线性振动控制方程；提出结构风敏感性判别策略和结构动力响应精细时频识别方法，揭示结构风致关键效应和动力时变行为；在大型风洞循环水槽海洋水池试验环境下，实现近水面风场物理模拟，开展深海平台塔桅气弹模型风洞试验研究。以期为深海平台高耸结构的抗强/台风安全提供理论与技术支撑

面向海洋油气资源开发需求，以深海平台抗风减灾和安全性为目标，开展了海洋风环境下深海平台及其上层高耸结构风浪致效应分析。研究了海洋近海面风环境与风特性，构建了海洋风风功率谱；揭示了风生浪物理耦联机制，构建了风浪耦联模型和风、浪荷载时程。以半潜式海洋平台为对象，开展了半潜式海洋平台系统的近海面风压风载数值模拟，建立了平台结构整体系统力学模型和动力方程，分析了半潜式海洋平台风浪致动力效应，开展了基于小波分析的动力效应时-频识别，揭示了平台结构系统的风致关键效应特性和动力时变行为。提出了改进多尺度扩展有限元法及其算法，并模拟了弹塑性材料疲劳破坏过程中宏观与微观裂纹的相互影响，微观夹杂与主裂纹的相互作用，揭示了构件材料的疲劳和损伤机理。提出了适用于钝体绕流和流固耦合分析的流体稳定化有限元法ICBS-ALE格式、3-TCBS格式和ICBS-SA格式，以及分区子迭代耦合算法格式和改进结合界面边界方法。建立了超长柔性立管流固耦合分析的高精度预测模型，揭示了轴向变截面波浪形三维圆柱水动力学特性。系统研究了典型钝体（群）的绕流形态和流致效应机理，主要包括并排静止双方柱绕流性态、三角形截面柱均匀流下的绕流与流致效应、静止四圆柱和三圆柱钝体的绕流性态、顺排静止方柱-振动圆柱的绕流和尾激振动、圆柱（群）钝体在均匀流和剪切流下的涡激振动效应与绕流性态等。此外，基于改进延迟分离涡模拟方法，研究了垂直轴风力机气动特性和波浪致纵摇运动下的漂浮式风力机气动特性。本项目研究成果可为深海平台结构系统的抗风浪安全性设计分析提供理论与技术支撑。