Advanced Numerical Framework for Wind Turbines in Atmospheric Boundary Layer Flow

现代风力涡轮机运行在非常复杂的湍流大气边界层（ABL）中，具有广泛的含能长度尺度和不同的大气稳定机制。当风力涡轮机与ABL相互作用时，叶片在旋转周期中经历了载荷和扭矩的显著变化。这直接影响到风力机的气动性能、发电量和叶片结构响应。当风力涡轮机排成阵列时，这个问题就会放大。在这种配置下，任何顺风涡轮机都在顺风涡轮机的尾流中运行，这增加了电力生产的损失，并且由于尾流相互作用而降低了疲劳寿命。******要准确预测在尾流中运行的风力涡轮机的非定常气动和结构行为将需要先进的数值模拟和模拟。然而，由于大雷诺数的高湍流分层流动和复杂的多物理场耦合，现有的模拟工具大多集中在与刚体风力机结构相互作用的平面上的非分层均匀流动条件。同时，由于叶片弹性变形叠加的相对运动分量、多层复合材料结构的几何非线性和材料非线性以及较大的问题尺寸，使问题进一步放大。******在上述挑战的激励下，拟议的研究计划侧重于开发一个预测的FSI框架，用于在实际大气条件下全尺寸和全几何复杂性的风力涡轮机计算。先进的多物理场模拟将提高我们对复杂地形下不同大气稳定机制下ABL湍流动力学的理解，以及它如何影响气动和叶片结构响应。这是首个具有完整几何和材料复杂性的多台风力涡轮机的FSI模拟，将更多地揭示尾流与涡轮机的相互作用及其对疲劳寿命的影响。提出的新型数值框架可以改善风力涡轮机的设计和优化过程，并通过提供高保真的输出来防止风力涡轮机主要部件的故障，而这些量是不易测量的。它将作为开发复杂风力涡轮机控制策略以最大化功率输出的宝贵工具。拟议的跨学科研究计划还将创建一个有价值的数据集，可供其他研究人员用于数值工具验证。******使用该计划，未来的高素质人才将在复杂工程问题的多物理场模拟方面发展强大的专业知识，这在加拿大和全世界的工业，国家实验室和学术界的需求日益增加。

Modern wind turbines operate in the very complex turbulent Atmospheric Boundary Layer (ABL) with a wide range of energy-containing length scales and with different atmospheric stability regimes. When wind turbines interact with the ABL the blades experience significant variations of the loading and torque during the rotation cycle. This directly affects the wind turbine aerodynamic performance, power production and blade structural response. The problem amplifies when wind turbines are arranged in arrays. In this configuration any downwind turbines operate in a wake of upwind turbines, which increase losses of power production and reduce the fatigue life due to wake interaction.******To accurately predict the unsteady aerodynamic and structural behavior of wind turbines operating in a wake will require advanced numerical modeling and simulations. Existing simulation tools, however, mostly focus on non-stratified, uniform flow conditions over flat surfaces interacting with rigid-body wind turbine structures due to highly-turbulent stratified flow with large Reynolds number and complex multi-physics coupling. At the same time the problem is amplified by presence of the components in a relative motion superimposed on elastic deformation of the blades, geometric and material nonlinearity of the multilayer composite structures and large problem size.******Motivated by the above challenges, the proposed research program focuses on the development of a predictive FSI framework for computation of wind turbines at full scale and with full geometrical complexity subjected to realistic atmospheric conditions. The advanced multiphysics simulations will improve our understanding of the turbulence dynamics in the ABL over complex terrain under different atmospheric stability regimes and how it affects the aerodynamic and blade structural response. The first-of-a-kind FSI simulations of multiple wind turbines with full geometric and material complexity will shed more light on wake-turbine interaction and how it affects fatigue life. The proposed novel numerical framework can improve design and optimization process of wind turbines and prevent failure of main turbine components by providing high-fidelity outputs for quantities of interest for which measurements are not readily available. It will serve as a valuable tool for developing sophisticated wind turbine control strategies to maximize power output. The proposed interdisciplinary research program will also create a valuable dataset that can be used by other researchers for numerical tools validation. ******Using this program the prospective highly qualified personnel will develop strong expertise in multiphysics simulations of complex engineering problems that is in increasing demand in industry, national laboratories, and academia in Canada and worldwide.