Exploiting the Wind Energy Resource through Aeroelastic Vibration and Torsional Flutter

风能是美国可再生能源计划的重要组成部分。作为这项工作的一部分，对大型系统（陆上和海上风力涡轮机）进行了彻底的研究。在“光谱”的另一边，微型风能已经被研究用于部署自给自足和自我充电的小型传感器。这两项技术都达到了高度成熟。相比之下，中尺度范围，即单户家庭或街区的中等规模，在很大程度上尚未开发，具有良好的增长和创新潜力。该项目使用简单紧凑的风能收集器，解决了中尺度水平对清洁能源的需求。发电机利用了叶片-翼型装置的扭转气动弹性不稳定性（即扭转颤振）。这项技术是可行的，因为它的操作机制比其他类似的收割技术更简单。研究计划将包括制造和测试一个缩小尺寸的原型装置。项目结果将展示该设备如何在城市环境中实施，并为电力和机械系统提供宝贵的能源。该项目将研究利用扭转颤振的风能采集器的技术可行性。扭转颤振是一种单模态气动弹性失稳现象，引起柔性体的发散振动。该项目将利用初步结果，其中一个数值模型被用来预测机械振动和感应电流。调查将包括分析、数值和实验阶段。本文的研究目标是：1)推进颤振能量“清除”的现有理论和分析模型；2)用于实验室验证和验证研究的原型装置的组装；3)对该单位进行全面部署和监控。第一个目标将考虑后临界动力学建模，非线性气动弹性力和响应，以及风能采集器关键参数的校准。第二个目标将通过设计一个缩小规模的装置来实现，然后通过风洞试验进行验证和验证，这将包括操作效率。最后，探索性研究将通过在建筑屋顶上的全尺寸部署进行。教育计划包括一系列面向不同受众（如学生、工程师）的拓展活动和演示。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Wind energy is an important component of the United States program for renewable energy. As part of this effort, large-scale systems (onshore and offshore wind turbines) have been thoroughly investigated. On the opposite side of the “spectrum”, micro-scale wind energy has been examined for the purposes of deployment of small sensors that are self-sufficient and self-recharging. Both technologies have reached an advanced maturity. In contrast, the meso-scale range, i.e., the intermediate scale of a single-family household or a street block, is largely unexplored and has good potential for growth and innovation. This project addresses the need for clean energy at the meso-scale level, using a simple and compact wind-based energy harvester. The power generator exploits the torsional aeroelastic instability (i.e., torsional flutter) of a blade-airfoil apparatus. The technology will be viable since its operational mechanism is simpler than other, similar harvesting technologies in the recent past. The research plan will include fabrication and testing of a reduced-scale prototype unit. The project results will demonstrate how the apparatus can be implemented in urban settings and provide a valuable energy source for electric and mechanical systems.The project will examine the technical feasibility of the wind energy harvester that exploits torsional flutter. Torsional flutter is a single mode aeroelastic instability phenomenon, which triggers a diverging vibration of a flexible body. The project will make use of preliminary results, in which a numerical model was employed to predict mechanical vibrations and induced currents. The investigation will include analytical, numerical and experimental stages. The objectives of this research are: 1) advancement of the current theory and analytical modeling of flutter energy “scavenging”; 2) assembly of a prototype unit used in the verification and validation studies in the laboratory; and 3) deployment and monitoring of the unit at full scale. The first objective will consider the modeling of post-critical dynamics, nonlinear aeroelastic force and response, and the calibration of the key parameters of the wind energy harvester. The second objective will be accomplished through the design of a reduced-scale unit, followed by validation and verification through wind tunnel tests, which will include operational efficiency. Finally, an exploratory study will be carried out through the deployment at full scale on a building roof. The educational plan includes a set of outreach activities and demonstrations for various audiences (e.g., students, engineers).This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.