CAREER: Experimental studies of turbulent inflow and wake relevant to marine hydrokinetic (MHK) energy conversion

1150797-Wosnik海洋流体动力(MHK)能量转换，包括潮汐/洋流和波能，可能是环境更可持续的发电方式之一。该项目的总体目标是更好地了解与海洋水动能转换有关的尺度上的湍流流入和尾流的时空结构。将使用一套最先进的实验流体动力学仪器来表征湍流，并将使用实验室和开放水域(潮汐河口)测试设施。研究的重点是潮汐能，但其结果也适用于海洋和河流的能量转换以及波能。智能优点：MHK能量转换设备受各种湍流尺度的影响。例如，最快的潮流经常出现在复杂的水深测量区域，这在MHK设备将要安装的位置产生了复杂的边界层和流动扭曲。初步测试表明，MHK装置的性能以及结构疲劳和故障与湍流密切相关。下游，MHK装置及其支撑结构产生的湍流可能会对水柱中的环境和生物产生影响。通常用于开放水域测量的坚固的声学多普勒海流剖面仪(ADCP)由于其工作原理限制在低采样率，这导致与MHK装置相关的湍流尺度的空间分辨率不足。另一方面，具有较高时间和空间分辨率的实验技术通常仅限于实验室环境。在本项目中，首先将在一个大截面组合双波水槽中测量湍流入流和水轮机尾迹，比较ADCP、多点声学多普勒测速(ADV)和水下高帧频粒子图像测速(HFR-PIV)，以建立每个仪器如何测量时空流动结构的基线。然后，将在开放水域潮汐能试验场测量湍流入流和水轮机尾迹，比较ADCP和ADV。来自实验室和开放水域部署的数据将用于数学建模，采用低维模型和随机估计技术，根据ADCP剖面和ADV参考测量来预测湍流状态。因此，该项目将填补仪器设备？规模差距？这是目前存在的。广泛影响：该项目将产生以前无法获得的关于与MHK相关的流动的时空结构的信息。它将提高我们对不同测量技术在MHK环境中的能力的理解，并创建通用的预测工具，这将使研究海洋环境中的其他现象和过程成为可能。这项研究的结果将实现更高保真的资源评估和更准确的能量转换设备评估，为流固耦合产生以前无法访问的流动数据，为设备阵列布局生成数据，促进环境影响评估，并最终导致改进设计。这样会对美国有帮助吗？MHK行业走向成功。将通过将研究纳入可再生能源和实验流体动力学高级/研究生课程、作为研究生培训一部分的工业研究机会、外联和继续教育以及参加大学开放活动、实验室参观和演示来实现研究和教育活动的一体化。外展活动将包括与NH海岸科学中心和NH儿童？S博物馆的活动。工程学中代表性不足的群体将通过UNH多样性办公室和学生社团积极招募，作为本科生研究人员和潜在的博士生参与拟议的研究。该项目将用于吸引对可再生能源、流量测量和湍流领域感兴趣的学生，并帮助培训推动这一新行业发展所需的劳动力。

1150797-WosnikMarine hydrokinetic (MHK) energy conversion, comprised of tidal/ocean current and wave energy, is likely one of the more environmentally sustainable ways to generate electricity. The overall objective of this project is to better understand the spatio-temporal structure of the turbulent inflow and wakes at scales relevant to marine hydrokinetic energy conversion. A suite of state-of-the-art experimental fluid dynamics instrumentation will be employed for turbulence characterization, and both laboratory and open water (tidal estuary) test facilities will be used. The study will focus on tidal energy, however, the results are applicable to ocean and river current energy conversion and wave energy as well. Intellectual Merit: MHK energy conversion devices are subjected to a wide range of turbulent scales. For example, the fastest tidal currents often occur in regions of complex bathymetry, which creates complex boundary layers and flow distortions in locations where MHK devices will be sited. Initial tests have shown that the performance of MHK devices, as well as structural fatigue and failure, are closely linked to turbulence. Downstream, turbulence generated by MHK devices and their support structures can have an effect on the environment and organisms in the water column. The robust Acoustic Doppler Current Profilers (ADCPs) commonly used for open water measurements are limited to low sampling rates due to their operational principle, which results in insufficient spatial resolution for scales of turbulence relevant to MHK devices. On the other hand, experimental techniques with higher temporal and spatial resolution are typically limited to laboratory environments. For this project, turbulent inflow and hydrokinetic turbine wakes will first be measured in a large cross-section combined tow-wave tank comparing ADCPs, multi-point Acoustic Doppler Velocimetry (ADV) and underwater high frame-rate Particle Image Velocimetry (HFR-PIV), to establish baselines on how each instrument measures spatio-temporal flow structures. Then turbulent inflow and hydrokinetic turbine wakes will be measured at an open-water tidal energy test site comparing ADCP and ADV. Data from the laboratory and the open-water deployments will be used in mathematical modeling with low-dimensional model and stochastic estimation techniques to predict turbulent flow states from ADCP profiles and ADV reference measurements. The project will thus fill an instrumentation ?scale gap? that currently exists.Broader Impacts: The project will produce previously unavailable information on the spatio-temporal structure of MHK-relevant flows. It will improve our understanding of the capabilities of the different measurement techniques in an MHK environment and create general predictive tools, which will make possible the study of other phenomena and processes in the marine environment. The results of this research will enable higher-fidelity resource assessment and more accurate energy conversion device evaluation, yield previously inaccessible flow data for fluid-structure interaction, generate data for device array layouts, facilitate environmental impact assessments, and, ultimately, lead to improved designs. It will thus help the United States? MHK industry to become successful. The integration of research and education activities will be achieved through inclusion of research in senior/graduate courses in Renewable Energy and Experimental Fluid Dynamics, industrial research opportunities as part of graduate training, outreach and continuing education, and participation in university open house events, laboratory tours and demonstrations. The outreach will include activities with the NH Seacoast Science Center and the NH Children?s Museum. Underrepresented groups in engineering will be actively recruited through the UNH Office of Diversity and student societies, to work on the proposed research as undergraduate researchers and potential Ph.D. students. The project will be used to attract students interested in the fields of renewable energy, flow measurement and turbulence, and help train the workforce necessary for advancing this new industry.