Advanced Numerical Framework for Wind Turbines in Atmospheric Boundary Layer Flow

现代风力涡轮机在非常复杂的湍流大气边界层（ABL）中运行，具有宽范围的含能长度尺度和不同的大气稳定性区域。当风力涡轮机与ABL相互作用时，叶片在旋转周期期间经历负载和扭矩的显著变化。这直接影响风力涡轮机的气动性能、功率生产和叶片结构响应。当风力涡轮机排列成阵列时，这个问题就放大了。在这种配置中，任何顺风涡轮机都在逆风涡轮机的尾流中操作，这增加了功率生产的损失并且由于尾流相互作用而降低了疲劳寿命。 为了准确预测在尾流中运行的风力涡轮机的非定常空气动力学和结构行为，需要先进的数值建模和模拟。然而，现有的模拟工具，主要集中在非分层的，均匀的流动条件下，平面与刚体风力涡轮机结构的相互作用，由于高度湍流分层流与大雷诺数和复杂的多物理耦合。与此同时，由于叶片的弹性变形、多层复合结构的几何和材料非线性以及大的问题尺寸上叠加的相对运动中的部件的存在，问题被放大。 受上述挑战的激励，拟议的研究计划侧重于开发一个预测FSI框架，用于在全尺寸下计算风力涡轮机，并具有实际大气条件下的完整几何复杂性。先进的多物理场模拟将提高我们对复杂地形上不同大气稳定性区域下ABL中湍流动力学的理解，以及它如何影响空气动力学和叶片结构响应。首次对具有完整几何和材料复杂性的多台风力涡轮机进行FSI模拟，将进一步揭示尾流-涡轮机相互作用及其如何影响疲劳寿命。所提出的新的数值框架可以改善风力涡轮机的设计和优化过程，并防止故障的主要涡轮机组件，通过提供高保真度的输出量的测量是不容易获得的利益。它将作为一个有价值的工具，开发先进的风力涡轮机控制策略，以最大限度地提高功率输出。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，未来的高素质人员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，这些问题在加拿大和全球的工业，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.