An Offshore Wind Energy Design Challenge: The Influence of Wind and Wave Load Combinations on the Extreme Response of Wind Turbines

本研究项目的主要目标是开发一个概率框架，该框架将包括以下特征：(a)描述叶片扫掠区域上流入湍流结构的随机场的时域模拟；(b)相关波浪运动学和推导的水动力载荷（与(a)中的风场一致）；(c)风力涡轮机的空气动力学响应（将模拟2至5兆瓦的公用事业规模的涡轮机）；(d)转子/叶片载荷和支撑结构（塔）载荷的随机描述；(e)有限载荷数据的统计外推，以预测与目标使用寿命（20年左右的回复期）相关的长期设计载荷。很少发表的研究涉及到海上风力涡轮机的基于站点特定可靠性的设计，并且唯一可用的（国际）设计规范规定了一个过于保守的设计负载情况的检查范围。这个项目将试图回答这个领域的一些悬而未决的问题。更广泛的影响：这项研究工作的核心是对研究生和本科生的教育，他们将发展统计建模、风和波场模拟、气动弹性和结构分析以及海上风力涡轮机在极限（极端）极限状态下的安全设计程序方面的技能。这些技能虽然不是典型课程的一部分，但对于我国快速发展的风能行业来说是迫切需要的，并且可以减少我们对西欧工程师技术咨询援助的日益依赖。教育和研究活动将集中在围绕风力涡轮机的空气动力学行为和近岸地点的复杂水动力载荷建模的领域。桑迪亚国家实验室将为学生提供实习机会；数据集和分析软件；技术监督;以及他们的工程师和PI及其学生之间的研究合作机会。在PI所在机构的工程机会均等办公室的帮助下，少数民族学生将通过德克萨斯研究经验（TREX）项目被选中作为本科生研究助理，并提供桑迪亚大学的暑期实习机会。

The main objective of this research project is to develop a probabilistic framework that will include the following features: (a) time-domain simulation of the random field describing the inflow turbulence structure over the swept area of the blades; (b) correlated wave kinematics and derived hydrodynamic loads (consistent with the wind field in (a)); (c) aerodynamic response of the wind turbines (utility-scale 2 to 5 MW turbines will be modeled); (d) stochastic descriptions of rotor/blade loads and support structure (tower) loads; and (e) statistical extrapolation of limited loads data to predict long-term design loads associated with the target service life (return periods on the order of 20 years). Very little published research relates to site-specific reliability-based design of offshore wind turbines, and the only (international) design code available prescribes an overly conservative envelope of design load cases for checking. This project will seek to answer some open questions in this area. Broader Impact: At the heart of this research effort is the education of graduate and undergraduate students who will develop skills in statistical modeling, wind and wave field simulation, aeroelastic and structural analysis, and safe design procedures for offshore wind turbines against ultimate (extreme) limit states. These skills, while not part of a typical curriculum, are urgently needed for a rapidly growing wind energy industry in this country and to limit our increased dependence on technical consulting assistance from engineers in Western Europe. Education and research activities will be focused in areas surrounding the modeling of the aerodynamic behavior of wind turbines and the complex hydrodynamic loading at near-shore sites. Sandia National Laboratories will provide internship opportunities for students; data sets and analysis software; technical oversight; and collaboration opportunities in research between their engineers and the PI and his students. With the help of the Equal Opportunity in Engineering (EOE) office at the PI's institution, minority students will be selected through the Texas Research EXperience (TREX) program as undergraduate research assistants and also offered summer internship opportunities at Sandia.