Theoretical and experimental analysis of the single-coil pulsed-NMR method for measuring fluid flow.

ABSTRACT

A theoretical and experimental analysis of the application of pulsed proton nuclear magnetic resonance (NMR) to the measurement of fluid flow has been made. Calculations of the detector signal line shapes, S(t), for a single-coil NMR laboratory experiment, were performed using a computer to identify the optimum choice of flow signature. The theoretical model included the influence of coil-field shape, coil length, and effects of flow phase. High flow rates, typical of arterial blood flow, were simulated. Good correlation between theory and experiment was observed. The maximum amplitude of the slope of the signal [dS(t)/dt] was found to be the optimum flow signature. The line shape S(t) was found to depend on flow phase. Comparison between theory and experiment provided a better understanding of the potential of NMR for measuring fluid or blood flow.