%0 Journal Article %J Magnetic Resonance Imaging %D 2007 %T Dispersion measurements using time-of-flight remote detection MRI %A Granwehr, J. %A Harel, E. %A Hilty, C. %A Garcia, S. %A Chavez, L. %A Pines, A. %A Sen, P. N. %A Song, Y. Q. %K flow %X

Remote detection nuclear magnetic resonance and magnetic resonance imaging can be used to study fluid flow and dispersion in a porous medium from a purely Eulerian point of view (i.e., in a laboratory frame of reference). Information about fluid displacement is obtained on a macroscopic scale in a long-time regime, while local velocity distributions are averaged out. It is shown how these experiments can be described using the common flow propagator formalism and how experimental data can be analyzed to obtain effective porosity, flow velocity inside the porous medium, fluid dispersion and flow tracing of fluid. (C) 2007 Elsevier Inc. All rights reserved.

%B Magnetic Resonance Imaging %V 25 %P 449-452 %8 May %@ 0730-725X %G English %U ://WOS:000246425100004 %N 4 %M WOS:000246425100004 %! Dispersion measurements using time-of-flight remote detection MRI %R Doi 10.1016/J.Mri.2006.11.011 %0 Journal Article %J Physical Review Letters %D 2005 %T Time-of-flight flow imaging using NMR remote detection %A Granwehr, J. %A Harel, E. %A Han, S. %A Garcia, S. %A Pines, A. %A Sen, P. N. %A Song, Y. Q. %K mri %X

A time-of-flight imaging technique is introduced to visualize fluid flow and dispersion through porous media using NMR. As the fluid flows through a sample, the nuclear spin magnetization is modulated by rf pulses and magnetic field gradients to encode the spatial coordinates of the fluid. When the fluid leaves the sample, its magnetization is recorded by a second rf coil. This scheme not only facilitates a time-dependent imaging of fluid flow, it also allows a separate optimization of encoding and detection subsystems to enhance overall sensitivity. The technique is demonstrated by imaging gas flow through a porous rock.

%B Physical Review Letters %V 95 %8 Aug 12 %@ 0031-9007 %G English %U ://WOS:000231247300028 %N 7 %M WOS:000231247300028 %! Time-of-flight flow imaging using NMR remote detection %R Doi 10.1103/Physrevlett.95.075503