PULSED NMR-STUDY ON THE FLOW OF FLUID

Pulsed NMR experiments of Carr-Purcell-Meiboom-Gill type have been performed on water flowing through a circular pipe. Spin echo signals were detected rf phase-sensitively in a highly stabilized electromagnet with a linear field gradient. The flow patterns studied were Poiseuille flows and turbulent flows. From measurements of the first spin echo signal amplitudes, information on velocity profile for various flow patterns were obtained, while from those of the second echo information on the velocity fluctuations were obtained. In turbulent states, measurements were performed both on the velocity component parallel to the axis of the pipe and on that perpendicular to it. The obtained data on turbulent flows seem to be explained satisfactorily by a modified stochastic theory of spin echo amplitudes. © 1979, THE PHYSICAL SOCIETY OF JAPAN. All rights reserved.