Effects of turbulent flow conditions on performance of wind and tidal turbines

英国是可再生能源的丰富来源，特别是在风能和海洋能源领域。陆上和海上风电每年贡献超过30太瓦时（TWh）的电力，相当于700多万户家庭的用电量。目前正在英国水域测试的波浪和潮汐装置的容量约为10兆瓦，比世界其他地区的总和还多。所有这些发电装置以及相关的系泊和基础都受到湍流条件的影响。这些湍流条件不仅自然存在于迎面而来的风或水流中，而且在流体流过它们时也由单个能量转换器产生。这导致了一个具有大范围重要长度和时间尺度的湍流流态，它改变了迎面而来的气流的剪切剖面和湍流强度，并对单个涡轮机和相关支撑结构的性能、疲劳和可靠性产生了巨大影响。湍流条件在改变一系列设备的相互作用方面也起着重要作用，这反过来又影响了农场的整体发电潜力。在这个项目中，我们的目标是进行一系列控制良好的实验，使我们能够系统地检查剪切和湍流对可再生能源发电的所有流体动力学相关方面的影响。目标是描述各种湍流剪切流条件下能源可用性、功率输出、推力、叶片负载和涡轮尾迹发展的变化。一个独特的流动设备，将能够独立改变剪切和湍流的特征，将被用来产生不同的速度剖面，保留大量的现实流动特征。利用先进的激光诊断技术进行高保真实验，以了解这些随需应变和可重复的湍流剪切流与模型级涡轮机之间的相互作用，这将使我们能够分离剪切和湍流对能量产生的影响。这种方法将使我们能够验证和改进当前的模型，并开发新的方法来确定能源农场的新位置，确定单个涡轮机的性能和可靠性，并预测整个风力和潮汐阵列的输出。

The UK is an abundant source of renewable power, especially in the wind and marine energy sectors. Onshore and offshore wind power contributes over 30 terawatt-hours (TWh) of electricity annually, equivalent to the electricity consumption more than 7 million homes. Wave and tidal devices that are currently being tested in the UK waters have a capacity of around 10MW, which is more than the rest of the world combined. All of these power-generating devices and associated moorings and foundations are affected by the turbulent conditions of the flow. These turbulent conditions are not only naturally present in the oncoming wind or water flow but are also generated by individual energy converters as the fluid flows past them. This leads to a turbulent flow regime that has a wide range of important length- and time-scales, which alter the shear profiles and turbulence intensities of the oncoming flow and has tremendous impact on the performance, fatigue and reliability of individual turbines and associated support structures. Turbulent conditions also play a significant role in altering the interaction in an array of devices, which in turn affect the overall energy generation potential of the farm. In this project, the aim is to carry out a series of well-controlled experiments that will allow us to systematically examine the effects of shear and turbulence on all fluid dynamically relevant aspects of renewable energy generation. The goal is to characterise the variations in energy resource availability, power output, thrust, blade loads and the wake development of turbines for a variety of turbulent shear flow conditions. A unique flow facility that will be able to vary the characteristics of shear and turbulence independently will be used to generate different velocity profiles that retain a plethora of realistic flow characteristics. High-fidelity experiments using advanced laser diagnostics will be carried out to understand the interaction between these on-demand and repeatable turbulent shear flows and model-scale turbines, which will then allow us to isolate the effects of shear and turbulence on energy generation. This approach will enable us to validate and improve the current models as well as develop new methods that can identify new locations for energy farms, determine the performance and reliability of individual turbines and predict the output of entire wind and tidal arrays.