Time-resolved tomographic particle image velocimetry (PIV) system

时间分辨断层扫描粒子图像测速 (PIV) 系统

• 批准号: RTI-2021-00385
• 负责人: Mohammadian, Majid
• 金额: $ 10.87万
• 依托单位: University of Ottawa
• 依托单位国家: 加拿大
• 项目类别: Research Tools and Instruments
• 财政年份: 2020
• 资助国家: 加拿大
• 起止时间: 2020-01-01 至 2021-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=718550
• 关键词: Time; resolved; tomographic; particle; image

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.

该提案提出了一种时间分辨层析粒子图像测速（TR-TOMO-PIV）系统，用于在环境流体力学、海岸和河流工程领域进行前沿研究。该系统可以帮助研究气候变化影响导致的基础设施需求变化。它可以高频测量体积而非平面上的 3D 速度场。时间分辨系统的频率为1000Hz，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）、污水与环境水域的混合（包括在各种条件下在沿海流和河流流中的混合）如并流和横流。特别是，拟议的设备对于在渥太华大学液压实验室的新玻璃墙水槽进行的专业研究特别重要，并为基础设施的安全设计提供了必要的详细信息。拟议的设备补充、加强和扩展了申请人目前正在进行的各种研究流，并使探索新的研究途径成为可能。该系统可以详细测量量化湍流特性所需的速度场，从而更好地了解高度湍流及其对液压基础设施周围的流动的影响，以及此类流动对结构影响的详细机制。在使用拟议设备的几个研究流可能性中，这里重点介绍三个研究流：1-工业排污口引起的羽流扩散，2-研究受海啸、快速风暴潮和山洪爆发影响的结构上的高度湍流超临界流，3-河流泛滥洪水事件中的能量耗散。提高对风暴和洪水等环境威胁的基础设施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。所提出的设备可以通过提供高分辨率（时间和空间）数据来支持增强型数值模型的开发，这些数据用于通过量化详细的湍流特征（例如湍流模型中的高阶项）来校准和验证数值模型。此外，可以使用 TR-TOMO-PIV 来估计湍流能量耗散，这可以提高对详细湍流机制和能量耗散的理解。与此处提出的研究流和拟议设备相关的可用数据有限，这将有助于更好地理解流体动力场形成的过程、更准确的模拟和卓越的基础设施设计。