Advances in Wind Turbine Analysis and Design for Sustainable Energy

随着中国从煤炭和天然气等传统碳基燃料转型，风能预计将成为未来几年可持续能源的主要来源。在实现国家风电机组的验收和使用之前，必须解决几个具体的技术问题。其中，最大的挑战是在保持性能的同时减少涡轮机的噪音污染。噪声的主要来源是由空气动力效应产生的，称为空气声学噪声。影响气动噪声强度的因素很多，包括进气湍流、涡轮叶片弹性和叶尖速度。对它们的相对影响的预测是非常具有挑战性的，并涉及到多个工程领域：空气动力学、湍流、结构动力学、材料和大气科学等。智力优势：这种拟议的影响将推动固定和旋转空气动力系统的计算建模技术的发展，并应用于风力涡轮机的分析和设计。在这项工作中开发的计算工具具有以下优点：(I)通过创建一种自适应的湍流建模方法来模拟壁面边界的非定常流动的保真度，(Ii)计算流体动力学和计算结构动力学(CFD-CSD)模拟之间的耦合过程的效率和精确度，因此可以在气动声学研究中包括改进的流固耦合效应，以及(Iii)自适应网格加密方法对非定常运动物体流动模拟的有效性。这些进展将通过与现有实验和计算数据的关联来验证。这些工具将在风力涡轮机社区感兴趣的设计应用中进行演示。更广泛的影响：如果成功，拟议的研究努力将对中大型风力涡轮机的有效设计产生重大而切实的影响。由于缺乏有效的预测工具，目前的设计方法严重依赖经验经验法则。转让给风能行业的技术将有助于预测和减少大型涡轮机产生的噪音污染，大型涡轮机是风力发电场部署的主要障碍，而小型涡轮机在居民区或附近使用。将噪音污染降低到不那么令人不快的水平，同时保持或改善当前的涡轮机性能特性，将使大片多风地形得到更大程度的利用，而不是完全孤立于为其提供电力的人口。靠近人口聚集区的封闭将缩短输电线路，减少相关损失。此外，更安静的叶片/叶尖将提高叶尖速度比，从而使驱动系统变得更轻，从而降低部署成本。大中型风力涡轮机的更高效设计也将对这种可持续能源的全球化产生积极影响，特别是在第三世界发展中国家。这项研究的结果将在国际会议上公布，并在期刊出版物上发表。此外，这些信息将通过GIT航空航天数字图书馆以与工程界和普通社区兼容的格式提供。研究结果还将作为范例和案例研究纳入佐治亚理工学院的研究生和本科生课程。

Wind energy is expected to be a major source of sustainable energy in the coming years as this country transitions from traditional carbon-based fuels such as coal and nature gas. Before national wind turbine acceptance and utilization can be realized, several specific technical issues must be addressed. Of these, the greatest challenge is the reduction of noise pollution by the turbines while maintaining performance. The primary source of noise is generated by aerodynamic effects and is known as aeroacoustic noise. Various factors influence the strength of the aeroacoustic noise including inflow turbulence, turbine blade elasticity and tip speeds. The prediction of their relative effects is incredibly challenging and draws upon a multiple engineering fields: aerodynamics, turbulence, structural dynamics, material and atmospheric sciences, etc. Intellectual merit: This proposed effect will advance the state-of-the-art in computational modeling techniques for both fixed and rotating aerodynamic systems, as applied to wind turbine analysis and design. The computational tools developed within this work advance the following: (i) the fidelity of wall-bounded, unsteady flow simulations by creating an adaptable turbulence modeling method, (ii) the efficiency and exact- ness of the coupling process between computational fluid dynamics and computational structural dynamics (CFD-CSD) simulations, so improved fluid-structure interaction effects can be included in aero-acoustic studies, and (iii) the effectiveness of adaptive mesh refinement methods for unsteady, moving-body flow simulations. These advances will be verified via correlations with existing experimental and computational data. These tools will be demonstrated in design applications of interest to the wind turbine community. Broader Impact: If successful, proposed research endeavor will have a significant and tangible impact on the effective design of moderate- to large-scale wind turbines. Current design methods rely heavily on empirical rules-of-thumb due to a lack of effective predictive tools. The technology transferred to the wind energy industry will assist in predicting and reducing noise pollution generated by the large turbines, a major hindrance in wind farm deployment, and by smaller turbines utilized in or near inhabited areas. Reducing the noise pollution to a less objectionable level, while maintaining or improving current turbine performance characteristics, will allow greater utilization of vast stretches of windy terrain not altogether isolated from the population for which it is providing power. Closure proximity to population areas will shorten transmission lines and reduce the associated losses. Furthermore, quieter blades/tips would enable increases in tip-speed ratios which will permit lighter drive-trains leading to lower deployment costs. More efficient design of large- and moderate-scale wind turbines will also positively impact the globalization of this sustainable energy source, in particular in developing third-world nations. The results of this research will be presented at international conferences and published in journal publications. In addition, the information will be made available via the GIT Aerospace Digital Library in formats compatible for both the engineering and general community. Results of the research will also be incorporated into both graduate and undergraduate courses at Georgia Tech as examples and case studies.