MRI: Instrumentation for Large Scale Holographic Particle Image Velocimetry with a Sample Volume of 25x25x25 cm^3, 500^3 Velocity Vectors and High Speed Data Processing System

摘要CTS-0079674 J。Katz，约翰霍普金斯大学本项目的目标是开发和实现一个大规模的全息粒子图像测速（HPIV）系统，用于测量复杂的湍流。这些数据将用于解决基本的湍流模型问题。该系统将能够测量高达25 x25 x25 cm ^3的样品体积上的瞬时三维速度分布，具有前所未有的分辨率，具有500 x500 x500的三维速度矢量阵列。湍流研究的两个主要途径提供了动力：i）高雷诺数湍流中速度增量的标度动力学和统计几何学; ii）湍流中大尺度和小尺度之间的关系及其对大涡模拟（LES）的次网格尺度建模的影响。三维数据将使PI和他的同事们能够解决高阶结构函数的异常标度行为，显着偏离Kolmogorov的预测; LES的湍流建模必须基于对各种长度尺度下湍流运动之间相互作用的理解。这样的理解需要的数据组成的分辨率很好的速度场，可以过滤，以获得亚网格尺度的应力，过滤速度及其gradients.Development和改进，这项技术最终将提供给整个社区的研究人员在广泛的领域中的传输现象是有意义的。包括涉及基础和应用流体力学、涉及气泡、颗粒和液滴输送的多相流以及环境流（如沉积物输送、大气科学（湍流和颗粒输送）和海洋学流、颗粒和浮游生物动力学等）的社区。

AbstractCTS-0079674J. Katz, Johns Hopkins UniversityThe objective of this project is to develop and implement a large scale Holographic Particle Image Velocimetry (HPIV) system for measuring complex turbulent flows. The data will be used for addressing fundamental turbulence modeling questions. The system will enable measurements of the instantaneous, three-dimensional velocity distribution over sample volumes of up to 25x25x25 cm^3, at an unprecedented resolution in scale, with arrays of 500x500x500, 3-D velocity vectors. Efficient and high speed processing tools will enable analysis of many holograms.Two main avenues of turbulence research provide motivation: i) scaling dynamics and statistical geometry of velocity increments in high Reynolds number turbulent flows, and ii) relationships between large and small scales in turbulence and their implications for subgird-scale modeling for Large Eddy Simulations (LES). The 3-D data will enable the PI and his colleagues to address the anomalous scaling behavior of high order structure functions that significantly deviate from Kolmogorov's predictions; Turbulence modeling for LES must be based on understanding of the interactions among turbulent motions at various length-scales. Such understanding requires data consisting of well-resolved velocity fields that can be the filtered to obtain the subgrid scale stresses, filtered velocity and its gradients.Development and improvements to this technology would eventually make it available to an entire community of researchers in a wide range of fields where transport phenomena are of significance. Included are communities involved in fundamental and applied fluid mechanics, multiphase flows involving transport of bubbles, particles and droplets as well as environmental flows, such as sediment transport, atmospheric sciences (turbulence and particle transport) and oceanography flow, particles and plankton dynamics, etc.).