Collaborative Research: Effect of Helicity on the Development of Free-Shear Turbulence at High Reynolds Number

合作研究：螺旋度对高雷诺数自由剪切湍流发展的影响

• 批准号: 1804214
• 负责人: Di Yang
• 金额: $ 27.81万
• 依托单位: University of Houston
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-06-15 至 2023-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1804214&HistoricalAwards=false
• 关键词: Collaborative; Research; Effect; Helicity; Development

Helicity is an inherent fluid flow property that physically relates to the local streamlines of a flow having helical-shaped structure. In the application of wind energy, a wind turbine can induce non-zero helicity in its turbulent wake. The speed of this wake flow has a strong impact on the power produced by a downstream turbine in a wind farm. This project will examine the effect of manipulating wake helicity generated by a vertical-axis wind turbine (VAWT) on the development of wake turbulence. In particular, the relationship between helicity and the turbulent entrainment of kinetic energy, which is critical to wake flow speed recovery, will be a primary focus. The project is a collaborative effort that exploits field, laboratory, and computational facilities using state-of-the-art equipment and novel methodologies to overcome the challenges of investigating highly turbulent flows. The project will also encompass education activities, such as involving undergraduate student researchers, facilitated by an emphasis on the connection between the fundamental physics of fluids and wind energy applications.The overall goal of this three-year project is to develop an understanding of the effect of helicity on the development of free-shear turbulence in high Reynolds number flows. A VAWT is employed as a 'helicity generator', where initial helicity in the turbine wake is controlled by turbine blade geometry and rotational speed, and the subsequent evolution of the turbulent wake is examined. Key components of this collaborative research effort will include: (1) field experiments to quantify wake helicity for utility-scale VAWTs in an atmospheric boundary layer flow using 3D particle tracking velocimetry, (2) wind tunnel experiments to achieve high spatio-temporal data of the VAWT wake using time-resolved stereoscopic particle image velocimetry, and (3) large eddy simulations to efficiently probe the effects of helicity by means not easily measured in the experiments. This combined effort offers an opportunity to investigate the physical effects of helicity at high Reynolds number, which contributes to basic fluid dynamics knowledge that could be used to inform turbulence models or more directly in applications such as wind farming.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.

螺旋度是一种固有的流体流动特性，其物理上与具有螺旋形结构的流动的局部流线相关。在风能应用中，风力涡轮机可以在其湍流尾流中产生非零螺旋度。这种尾流的速度对风电场下游涡轮机产生的电力有很大影响。该项目将研究操纵垂直轴风力涡轮机 (VAWT) 产生的尾流螺旋度对尾流湍流发展的影响。特别是，螺旋度与动能的湍流夹带之间的关系将成为主要关注点，这对于尾流速度恢复至关重要。该项目是一项协作努力，利用现场、实验室和计算设施，使用最先进的设备和新颖的方法来克服研究高度湍流的挑战。该项目还将包括教育活动，例如让本科生研究人员参与，并通过强调流体基础物理学和风能应用之间的联系来促进。这个为期三年的项目的总体目标是加深对影响的理解螺旋度对高雷诺数流动中自由剪切湍流发展的影响。 VAWT 被用作“螺旋度发生器”，其中涡轮尾流的初始螺旋度由涡轮叶片几何形状和旋转速度控制，并检查湍流尾流的后续演变。这项合作研究工作的关键组成部分将包括：(1) 使用 3D 粒子跟踪测速技术量化大气边界层流中公用事业规模 VAWT 尾流螺旋度的现场实验，(2) 风洞实验以获得高时空数据使用时间分辨立体粒子图像测速技术的 VAWT 尾流，以及 (3) 大涡模拟，通过实验中不易测量的方法有效地探测螺旋度的影响。这项共同努力提供了一个研究高雷诺数螺旋度物理效应的机会，这有助于获得基本的流体动力学知识，这些知识可用于为湍流模型提供信息或更直接地用于风力发电等应用。该奖项反映了 NSF 的法定使命和通过使用基金会的智力价值和更广泛的影响审查标准进行评估，该项目被认为值得支持。

项目成果

Large-eddy simulations of turbulent flows in arrays of helical- and straight-bladed vertical-axis wind turbines

螺旋叶片和直叶片垂直轴风力涡轮机阵列中湍流的大涡模拟

• DOI: 10.1063/5.0172007
• 发表时间: 2023-12
• 期刊: Journal of Renewable and Sustainable Energy
• 影响因子: 2.5
• 作者: Gharaati, Masoumeh;Wei, Nathaniel J.;Dabiri, John O.;Martínez;Yang, Di
• 通讯作者: Yang, Di

Large-eddy simulation of helical- and straight-bladed vertical-axis wind turbines in boundary layer turbulence

边界层湍流中螺旋叶片和直叶片垂直轴风力机的大涡模拟

• DOI: 10.1063/5.0100169
• 发表时间: 2022-09
• 期刊: Journal of Renewable and Sustainable Energy
• 影响因子: 2.5
• 作者: Gharaati, Masoumeh;Xiao, Shuolin;Wei, Nathaniel J.;Martínez;Dabiri, John O.;Yang, Di
• 通讯作者: Yang, Di