NMR imaging of flow velocity in porous media
NMR imaging of flow velocity in porous media
复制标题
多孔介质中流速的核磁共振成像
DOI：
10.1002/aic.690450302
复制
发表时间：
1999
期刊：
影响因子：
3.7
通讯作者：
A. T. Watson
中科院分区：
文献类型：
--
作者：
Chii;A. T. Watson
评价了两种基于脉冲梯度场激励回波技术的核磁共振速度成像方法在多孔介质渗流测量中的应用。选择速度成像实验的空间分辨率和动态尺度来表征流体分子复杂运动的宏观行为。数据解释的理论公式，并证明了在玻璃珠包和砂岩样品的水流实验数据。研究的速度成像方法包括使用流动引起的相移和空间分辨速度分布的测量。结果表明，相移法不适用于某些多孔介质。相比之下，空间分辨速度分布的测量不仅允许确定平均速度的图，而且还提供关于图像的每个基本体积内的速度场的信息。
Two NMR velocity imaging methods based on the pulsed field gradient stimulated-echo technique are evaluated for the measurement of fluid flow in porous media. The spatial resolution and dynamic scale of velocity imaging experiments are chosen to represent the macroscopic behavior of the complex motion of fluid molecules. A theoretical formulation for data interpretation is presented and demonstrated with experimental data for water flow in a glass-bead pack and sandstone samples. Velocity imaging methods investigated include the use of flow-induced phase shifts and the measurement of spatially resolved velocity distributions. The results show that the phase-shift method is not suitable for some porous media. By contrast, the measurement of spatially resolved velocity distributions not only allows a map of mean velocity to be determined, but also provides information about the velocity field within each elemental volume of the image.