EAGER: Visualizing Land-to-Atmosphere Exchanges due to Wind Turbines Under Stratified Flows

对于风力涡轮机阵列，通过引入大气热稳定或不稳定分层来增强陆地-大气交换。稳定的大气湍流边界层（ATBL）减少了流动湍流。据称，风力涡轮机阵列在稳定条件下（通常在傍晚）使土地干燥，因此可能对农业产生影响，也可能影响风蚀。了解复杂的相互作用的分层ATBL和风力涡轮机阵列是本研究的目标。为了获得正确的理解，风电场内发生的能量和热通量之间的关系以及它们与风力涡轮机产生的周期性尾流之间的相互作用至关重要。在这项研究中，风洞实验在波特兰州立大学计划可视化的分层湍流边界层的混合过程，并没有风力涡轮机。实验的目标是控制分层仔细和参数化，然后在生成的流进行流动可视化。单个风力涡轮机和ATBL之间的湍流垂直运动/交换将指导关于陆地-大气交换的结论，从而激发进一步的问题。这项研究可能会对大规模部署此类技术所需的理解产生重大影响。这些初步的可视化将激发进一步研究这些流动的一个更大的实验套件，考虑到风力涡轮机阵列，而不是一个单一的涡轮机。这些初步信息将有助于为未来提交NSF流体动力学计划和/或NSF可持续发展能源计划准备更详细的计划，以详细研究这种相互作用。

0953053CalFor wind turbine arrays, a land-to-atmosphere exchange is enhanced by introducing atmospheric thermal stable or unstable stratification. The stable atmospheric turbulence boundary layer (ATBL) reduces flow turbulence. Wind turbine arrays have been claimed to dry the land during stable conditions (typically during evening), thus having a possible impact on agriculture, also possibly affecting wind erosion. Understanding complex interactions of a stratified ATBL and a wind turbine array is the goal of this study. To acquire the proper understanding, the relationship between the energy and heat fluxes occurring within the wind farm and their interactions with the periodic wake generated by the wind turbine is vital. In this study, wind tunnel experiments at Portland State University are planned to visualize the mixing processes of a stratified turbulent boundary layer with and without a wind turbine. The experimental objectives are to control stratification carefully and parametrically and then perform flow visualization in the generated flows. Vertical motions/exchanges of turbulence between a single wind turbine and ATBL will guide conclusions about the land-to-atmosphere exchanges, thus motivating further questions. This study can have significant impact on understanding needed for large-scale deployment of such technology. These preliminary visualizations will motivate further studies of these flows for a larger suite of experiments, taking into account wind turbine array rather than a single turbine. This preliminary information will help prepare more detailed plans for future submissions to NSF-Fluid Dynamics program and/or the NSF-Energy for Sustainability program to study such interactions in detail.