Fluctuations in Flows by NMR

小行星9404778福岛 核磁共振成像（NMRI）测量两相流中的波动参数的潜在用途将进行探讨。 两相参数包括固液速度脉动、混合物密度脉动、扩散系数和速度相关系数。 关键问题是减少每次成像所需的时间。 另一个目标是开发必要的技术来解释NMRI确定的波动及其相关性，并定义该方法的局限性。 目前的光学方法不适用于大多数不透明的液-固混合物系统，特别是在工业应用中。 Lovelace研究所将提供新的设备，以减少磁铁中的涡流，这是该项目的主要硬件要求。 通过控制涡流，在初步测试中用于单独测量的梯度切换速度增加了三个数量级。 预计对于64 X64网格，在二维域中的速度成像可以在0.05秒内执行，这将在质量上上级先前的结果，并且将足够快以用于具有相对低雷诺数的湍流中的速度波动。 实验将在一个相对简单的几何结构中进行，其中有两相波动参数的参考数据。 预算包括与西雅图的华盛顿大学合作的教育类费用。 先进的NMRI作为一种通用的非破坏性测量技术，可用于控制化学制造和其他加工行业中的多相流系统。 如果成功，本项目将证明使用NMRI进行大量两相流测量的可行性，对推进多相流科学（新仪器，不透明多相系统的参考数据集）和技术（非侵入式原位传感器）具有重要影响。 ***

9404778 Fukushima The potential use of nuclear magnetic resonance imaging (NMRI) for measuring fluctuating parameters in two-phase flow will be explored. The two-phase parameters include solids and liquid velocity fluctuations, mixture density fluctuations, diffusion coefficients and velocity cross-correlations. The key issue is the reduction of the time necessary for each imaging. Other objective is developing techniques necessary to interpret the fluctuations and their correlations determined by NMRI, and to define the limits of the method. Current optical methods are not suitable for most liquid-solid mixture systems which are opaque, particularly in industrial applications. The Lovelace Institutes will provide new equipment for the reduction of eddy currents in the magnets, which is the main hardware requirement of the project. The gradient switching speed for individual measurements in the preliminary tests has been increased by three orders of magnitude by controlling the eddy currents. It is expected that velocity imaging in a two-dimensional domain could be performed in 0.05 seconds for a 64X64 mesh, which would be qualitatively superior to previous results and would be sufficiently fast to be used for velocity fluctuations in turbulent flows with relatively low Reynolds number. The experiments will be performed in a relatively simple geometry for which there are reference data on two-phase fluctuating parameters. The budget covers educational type of expenses, in collaboration with the University of Washington in Seattle. Advanced NMRI has application as a versatile non-destructive measuring technique to control multiphase flow systems in chemical manufacturing and other processing industries. If successful, the present project will demonstrate the feasibility of using NMRI to a large group of two-phase flow measurements, with important impact on advancing the science (new instrumentation, reference sets of data for opaque multiphase system s) and technology (nonintrusive in-situ sensors) of multiphase flow. ***