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)进行了彻底的调查。在“光谱”的另一边，为了部署自给自足和自我充电的小型传感器，已经对微尺度风能进行了研究。这两项技术都已经达到了高度成熟。相比之下，中观范围，即单户家庭或街道街区的中等规模，在很大程度上尚未开发，具有良好的增长和创新潜力。该项目利用一台简单紧凑的风能收割机，解决了中尺度上对清洁能源的需求。该发电机利用叶片-翼型装置的扭转气动弹性不稳定性(即扭转颤振)。这项技术将是可行的，因为它的运行机制比最近过去的其他类似收获技术更简单。研究计划将包括制造和测试一个缩小规模的原型单元。该项目的结果将展示如何在城市环境中实施该设备，并为电气和机械系统提供宝贵的能源。该项目将检验利用扭转颤振的风能收集器的技术可行性。扭转颤振是一种引起柔体发散振动的单模气动弹性失稳现象。该项目将利用初步结果，其中使用了一个数值模型来预测机械振动和感应电流。研究将包括分析、数值和实验阶段。这项研究的目标是：1)发展颤振能量“清除”的现有理论和分析模型；2)组装用于实验室验证和确认研究的原型单元；3)全面部署和监测该单元。第一个目标将考虑风能收集器的后临界动力学、非线性气动弹性力和响应的建模以及关键参数的标定。第二个目标将通过设计一个缩小规模的装置来实现，随后将通过风洞试验进行验证和验证，其中将包括运行效率。最后，通过在建筑物屋顶上的全面部署进行探索性研究。该教育计划包括一系列面向不同受众(如学生、工程师)的外展活动和示范。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势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.