Liquid flow velocity determination by NMR imaging

The authors review quantitative liquid flow determination by a subset of nuclear magnetic resonance (NMR) called magnetic resonance imaging (MRI). These imaging techniques yield the velocity distribution of steady flows as well as the spatial distribution of a parameter characterizing turbulence. Three methods considered, with emphasis on the first two, are (1) bolus tracking after frequency encoding, (2) phase behavior of the nuclear spins traveling in a magnetic field gradient, and (3) the snapshot method for tracking slowly moving, chemically distinguishable species.<<ETX>>