Collaborative Research: Large-scale kinetic energy entrainment in the wind turbine array boundary layer - understanding and affecting basic flow physics

合作研究：风力涡轮机阵列边界层中的大规模动能夹带 - 理解和影响基本流动物理

• 批准号: 1133800
• 负责人: Charles Meneveau
• 金额: $ 29.48万
• 依托单位: Johns Hopkins University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-01-01 至 2015-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1133800&HistoricalAwards=false
• 关键词: Collaborative; Research; Large; scale; kinetic

1133800 PI Meneveau/1133993 PI CastilloThe objective of this project is to develop and apply experimental and computational tools for predicting and improving wind farm performance by placing particular attention on large scales of turbulence and vertical fluxes of kinetic energy that are of great significance for large arrays of wind turbines. Much effort has been devoted in recent years to increasing the efficiency of individual wind turbines, assuming a given inflow in front of the turbine. Also, understanding how wakes affect the performance of downstream turbines and modeling superpositions of multiple such wakes has received considerable attention; however, there has been relatively little fundamental understanding of how a large array of wind turbines interacts with the turbulent atmospheric boundary layer at larger scales in the wind turbine array boundary layer (WTABL). Recent research has demonstrated that an important performance-limiting factor for large wind farms is the rate at which kinetic energy can be entrained into the array from the flow aloft, above the wind turbines. No matter how efficient an individual wind turbine is, or how well it can adapt to an upstream wind turbine, ultimately it is the vertical flux of kinetic energy into the overall array that largely determines how much power can be extracted from the atmospheric flow. The questions addressed in this project aim at better understanding the limiting factors and the effects of different scales of turbulence on vertical entrainment processes. The resulting models should guide wind turbine placement strategies and possible flow modifications so that vertical entrainment rates can be increased. Specifically, wind tunnel experiments coupled with large-eddy simulations (LES) will be employed to address the following research questions: (a) What are the essential differences between the developing and the fully developed WTABL? (b) What is the relative contribution from streamwise large-scale coherent vortices to vertical entrainment of kinetic energy? (c) What are the space-time correlations of hub-height velocity and power output between different wind turbines in the array? (d) Are there particular arrangements of wind turbines in the array that increase, on average, the entrainment? and (e) Can large-scale flow structures be affected through rotor modifications to increase such entrainment? Addressing such questions requires the ability to experiment under the highly controlled and reproducible conditions that can be afforded in the wind tunnel experiments and computer simulations. The data will be supplemented with comparisons with relevant new field data from a large wind farm. Broader impacts: The robust growth of wind energy implies the possibility that large portions of the land and near-shore surface of the US and the world may ultimately be used for large wind farms. Predicting and better understanding the physical processes coupling the modified surface and atmosphere under such conditions is a timely and critical area of research. Through project activities the PIs will help train the next generation of engineers and scientists with the necessary tools and insights to help reach the US goal of 20% wind energy by 2030. Graduate education/mentoring will stress the interplay between wind tunnel experimentation, computer simulation and field data analysis. International (Switzerland, Spain) and industrial experiences (General Electric) will also be emphasized in this project. Recruiting and outreach will leverage both PIs' ongoing efforts to recruit US Hispanic graduate students through contacts in Puerto Rico (NSF-AGEP and LSAMP), as well as an IGERT at JHU on modeling complex systems. A GK-12 at RPI on energy and environment will leverage NSF resources in training teachers on wind energy issues. The PI's ongoing outreach to a Baltimore high school will be continued, providing research experiences for high-school juniors and seniors.

1133800 PI MENEVEAU/1133993 PI CASTILLOTHE该项目的目标是开发和应用实验和计算工具，通过将大量的湍流和垂直磁力范围放在风力涡轮机阵列中具有重要意义，以预测和改善风电场性能。 近年来，假设在涡轮机前的流入，近年来已经大量努力提高了单个风力涡轮机的效率。同样，了解唤醒的方式如何影响下游涡轮机的性能和对多个此类唤醒的叠加的建模也受到了极大的关注。但是，对大量风力涡轮机如何与风力涡轮机阵列边界层（WTABL）较大尺度上的湍流大气边界层相互作用的基本了解相对较少。最近的研究表明，大型风电场的重要性能限制因素是可以从高高的风力涡轮机上方的流动流入阵列中的动能的速度。无论单独的风力涡轮机有多效率，或能够适应上游风力涡轮机的能力，最终，动能的垂直通量向整体阵列中的垂直通量很大程度上决定了从大气流中提取多少功率。 该项目中解决的问题旨在更好地理解不同湍流对垂直夹带过程的限制因素和影响。 最终的模型应引导风力涡轮机放置策略和可能的流动修改，以便可以提高垂直夹带率。具体而言，将采用风洞实验以及大涡模拟（LES）来解决以下研究问题：（a）开发与完全开发的WTABL之间有什么基本差异？ （b）流向大规模相干涡旋到动能垂直夹带的相对贡献是什么？ （c）阵列中不同风力涡轮机之间的集线器高速速度和功率输出的时空相关性是什么？ （d）阵列中风力涡轮机的特殊排列平均增加了吗？ （e）大规模流量结构是否可以通过转子修改影响以增加这种夹带？解决此类问题需要在风洞实验和计算机模拟中可以提供的高度控制和可重复的条件下进行实验。这些数据将与来自大型风电场的相关新现场数据进行比较。 更广泛的影响：风能的强大增长意味着最终将大部分土地和近岸表面的大部分地区用于大型风电场。预测并更好地理解在这种条件下将修饰的表面和大气耦合的物理过程是及时且关键的研究领域。通过项目活动，PI将帮助培训下一代工程师和科学家的必要工具和见解，以帮助达到20％的风能到2030年的目标。研究生教育/指导将强调风洞实验，计算机模拟和现场数据分析之间的相互作用。国际（瑞士，西班牙）和工业经验（通用电气）也将在该项目中得到强调。招募和外展将通过波多黎各的联系（NSF-AGEP和LSAMP）以及JHU的IGERT进行建模复杂系统，从而利用PIS的持续努力来招募我们的西班牙裔研究生。 RPI的GK-12关于能源和环境将利用NSF资源在培训风能问题的培训教师中。 PI将继续向巴尔的摩高中进行持续的宣传，为高中生和老年人提供研究经验。