Vertical-Axis Wind Turbine Blade Vibration Modeling for Improved Reliability

垂直轴风力涡轮机叶片振动建模以提高可靠性

• 批准号: 1435126
• 负责人: Brian Feeny
• 金额: $ 25万
• 依托单位: Michigan State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-09-01 至 2019-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1435126&HistoricalAwards=false
• 关键词: Vertical; Axis; Wind; Turbine; Blade

Meeting the goal of 20 percent US energy by wind by 2030 will require a diverse fleet of wind energy harvesters. Wind turbines of various styles and of increasing size will need to be installed in a variety of environments including off shore. Maintenance and repair of very large turbines can be costly and involve significant down time, thereby challenging the development of affordable wind energy. Currently, horizontal-axis wind turbines (HAWTs) are the most popular type, with vertical-axis wind turbines (VAWTs) being the next most common. One thing that has hindered the development of VAWTs is their reputation for having vibration and fatigue problems. This reputation was established well before the development of modern blade materials. But VAWTs have some important advantages. These include independence of wind direction, reduced tower size, lower center of mass, and lower generator placement. Furthermore, HAWT size may be limited by gravity. Also, VAWT efficiency improves when placed in wind-farm arrays. Thus, VAWTs may turn out to be better for some applications, including large off-shore installations, and are therefore getting renewed interest. To date, VAWTs have been modeled in much less depth than HAWTs. These circumstances all converge to the need for better models for VAWTs, including VAWT blade vibration. The purpose of this work is to develop a model for VAWT blade vibration, and to use the model to understand the role of VAWT blade parameters on vibration, to enable the design of reliable VAWTs in the future. In this work, vibration models of H-rotor VAWT blades will be formulated. The simple geometry of H-rotor blades allows the work to focus on the complexity of the mechanics of VAWT function. The model will include nonlinear beam theory and a semi-empirical model of the nonlinear aerodynamic forces. Preliminary insight into the model suggests the existence of parametric and direct excitation, and nonlinearity, all of which together can interact to produce a variety of resonances and instabilities. Reduced-order modeling and asymptotic analysis will lead to identification of resonances and instabilities. Critical cases will be simulated numerically in more depth. The result will be an understanding of the mechanisms of resonances and instabilities of VAWT blades, as well as the role of parameters, leading to design recommendations for increased reliability, reduced maintenance costs, and less down time.

要实现到 2030 年美国 20% 的能源来自风能的目标，需要多样化的风能采集机群。 各种类型和尺寸不断增加的风力涡轮机需要安装在包括离岸在内的各种环境中。 大型涡轮机的维护和修理成本高昂，并且需要大量停机时间，从而对开发负担得起的风能提出了挑战。 目前，水平轴风力涡轮机 (HAWT) 是最流行的类型，垂直轴风力涡轮机 (VAWT) 是第二常见的类型。 阻碍垂直轴风力机发展的一件事是其存在振动和疲劳问题的名声。 这种声誉早在现代刀片材料发展之前就已建立。 但垂直轴风力机有一些重要的优势。 这些包括风向独立性、减小的塔尺寸、较低的质心和较低的发电机放置位置。 此外，HAWT 的尺寸可能受到重力的限制。 此外，当放置在风电场阵列中时，VAWT 效率也会提高。 因此，VAWT 可能更适合某些应用，包括大型海上设施，因此重新引起人们的兴趣。 迄今为止，垂直轴风力机的建模深度远低于水平轴风力机。 这些情况都集中到需要更好的 VAWT 模型，包括 VAWT 叶片振动。 这项工作的目的是开发一个 VAWT 叶片振动模型，并使用该模型来了解 VAWT 叶片参数对振动的作用，以便将来能够设计出可靠的 VAWT。在这项工作中，将制定 H 转子 VAWT 叶片的振动模型。 H 转子叶片的简单几何形状使工作能够集中于 VAWT 功能的力学复杂性。 该模型将包括非线性梁理论和非线性气动力的半经验模型。 对模型的初步了解表明存在参数和直接激励以及非线性，所有这些相互作用可以相互作用产生各种共振和不稳定性。 降阶建模和渐近分析将导致共振和不稳定性的识别。 将对关键情况进行更深入的数值模拟。 其结果将是了解 VAWT 叶片的共振和不稳定性机制以及参数的作用，从而提出提高可靠性、降低维护成本和减少停机时间的设计建议。