Time-resolved tomographic particle image velocimetry (PIV) system

本文提出了一种时间分辨层析粒子图像测速（TR-TOMO-PIV）系统，用于环境流体力学、海岸和河流工程的前沿研究。该系统可以帮助研究由于气候变化的影响而不断变化的基础设施需求。它可以在高频率下测量体积而不是平面上的3D速度场。时间分辨系统的频率为1000 Hz，以便能够捕获速度场中的高频过程。该系统可用于广泛的应用，包括沿海流和水利基础设施周围的速度场测量、超临界流、河流流（包括漫滩洪水）、流出物与环境沃茨的混合（包括在各种条件下（如顺流和横流）在沿海流和河流流中的混合）。特别是，拟议的设备可以在新的玻璃壁水槽在渥太华大学的水力实验室进行的专业研究，并提供必要的基础设施的安全设计的详细信息是特别重要的。拟议的设备补充、加强和扩大了申请人目前正在进行的各种研究，并使其有可能探索新的研究途径。该系统允许对速度场进行详细测量，所述速度场用于量化湍流特性，所述湍流特性用于更好地理解高度湍流的流动及其对水力基础设施周围的这种流动的影响以及这种流动对结构的影响所涉及的详细机制。在几个研究流的可能性，使用拟议的设备，三个研究流在这里强调：1-分散的羽流引起的工业排污口，2-调查的高度湍流超临界流的结构受到海啸，快速风暴潮和山洪暴发，3-能量耗散在河流漫滩洪水事件。加强对基础设施在风暴和洪水等环境威胁下的脆弱性的理解和建模尤为重要。此外，还需要研究改进上述各种应用中的数值模型。拟议的设备可以通过提供高分辨率（时间和空间）数据来支持增强的数值模型的开发，这些数据将用于通过量化详细的湍流特性（例如湍流模型中的高阶项）来校准和验证数值模型。此外，利用TR-TOMO-PIV技术可以估算湍流能量耗散，从而加深对湍流机理和能量耗散的理解。有限的数据是可用的研究流在这里提出的和拟议的设备，这将导致更好地理解的过程中形成的水动力场，更准确的模拟，和上级基础设施设计。

A time-resolved tomographic particle image velocimetry (TR-TOMO-PIV) system is proposed in this proposal to conduct cutting-edge research in environmental fluid mechanics, coastal, and river engineering. The system can help study the changing needs of infrastructure as a consequence of the effects of climate change. It can measure a 3D velocity field over a volume rather than a plane at a high frequency. The frequency of the time-resolved system is 1000Hz to be able to capture high-frequency processes in the velocity field. The system can be used for a wide range of applications including velocity filed measurement in coastal flows and around hydraulic infrastructure, supercritical flows, river flows including overbank flood flows, mixing of effluents with ambient waters including mixing in coastal and river flows in various conditions such as co-flow and crossflow. In particular, the proposed equipment can be of particular importance for the specialty research conducted at the new glass-walled flume at the Hydraulic Laboratory at the University of Ottawa and provide detailed info necessary for safe design of infrastructures. The proposed equipment complements, strengthens and expands various research streams currently in progress by the applicants and makes it possible to explore new research avenues. The system allows for detailed measurement of the velocity field required for quantifying turbulence characteristics required for better understanding of highly turbulent flows and their effects such flows around hydraulic infrastructure as well as detailed mechanisms involved in impact of such flows on the structure. Among several research stream possibilities using the proposed equipment, three research streams are highlighted here: 1- Dispersion of plumes caused by industrial outfalls, 2- Investigation of highly turbulent supercritical flows on structures impacted by tsunami, rapid storm surges and flash floods, 3- Energy dissipation in river overbank flood events. Improving the understanding and modeling of infrastructure vulnerability against environmental threats such as storms and floods is of particular importance. Moreover, research is needed in improvement of the numerical models in various above-mentioned applications. The proposed equipment can support development of enhanced numerical models via providing high-resolution (temporal and spatial) data to be used for calibration and validation of numerical models by quantifying detailed turbulence characteristics such as higher order terms in turbulence models. Moreover, turbulent energy dissipation can be estimated using the TR-TOMO-PIV which can improve understanding about detailed turbulence mechanism and energy dissipation. Limited data is available related to the research streams proposed here and the proposed equipment which will lead to a better understanding of the processes shaped by hydrodynamic fields, more accurate simulations, and superior infrastructure design.