Achieving high energy extraction with multiple vertical axis wind turbines

垂直轴风力涡轮机(VAWT)的一个新发现的优势是，它们的转子可以紧密地放置在一起，而不会显著降低效率。实验结果表明，隔开4个转子直径的涡轮的性能与孤立涡轮一样好。由多台变风量风电机组组成的风电场，其出力应明显高于现有的水平轴风电场。为了进一步演示这一概念，可以利用计算流体力学(CFD)，但需要改进CFD的现状，以达到模拟多个VAWT所需的精度和合理的计算时间。作者的初步分析还表明，三个面向风向的水轮机的功率系数都有所增加，但影响功率增加的参数仍有待确定。该研究计划将开发一种准确、快速的CFD模拟工具来研究多个VAWT之间的相互作用。需要此模拟工具来演示和量化在近距离使用多个VAWT的好处。对紧凑型变风量风电机组相关现象的了解可以导致风能行业的一场革命，因为从风电场中提取的能量可以显著增加。该研究项目将通过培养CFD和风能领域的两名博士生和三名硕士研究生来做出贡献。

A newly discovered advantage of vertical axis wind turbines (VAWT) is that their rotors can be placed close together without significant loss of efficiency. Experimental results indicate that turbines separated by a distance of 4 rotor diameters perform as well as isolated turbines. The power extraction of a wind farm composed of multiple VAWT should be significantly higher than the existing wind farms exploiting horizontal axis wind turbines (HAWT). To further demonstrate this concept, computational fluid dynamics (CFD) can be utilized but the current state of CFD needs to be improved to achieve the required accuracy and reasonable computing time to simulate multiple VAWT. An initial analysis by the author has also shown an increase of the power coefficient for three turbines facing the wind direction, nevertheless the parameters that affect the increase in power remain to be determined. The research program described in this proposal will develop an accurate and fast CFD simulation tool to study multiple VAWT interaction. This simulation tool is needed to demonstrate and to quantify the benefit of using multiple VAWT in close proximity. The understanding of the phenomena related to closely packed VAWT can lead to a revolution in the wind energy industry because energy extract from wind farms can be significantly increased. This research program will contribute by training two PhD students and three master students in the field of CFD and wind energy.