Optimization of continuous wave nuclear magnetic resonance to determine in situ volume fractions and individual flow rates in two component mixtures.
In this paper, the optimization of continuous wave nuclear magnetic resonance in two component flowing mixtures to determine the in situ volume fractions and the individual component flow rates is described from both an analytical and an experimental point of view. A simple and accurate measuring system is discussed and the analytical and experimental results are compared for oil-water mixes. The use of a relatively long polarizing magnet prior to the highly homogeneous detector magnet has been shown to improve the flow-rate range considerably and makes feasible a relatively inexpensive, accurate, and genuine two-phase or two component flow meter. By measuring the optimum value of H(1), or the rf level required to produce that optimum value, and by simultaneously measuring the magnitude of the signal at that time, both the in situ volume fraction and the flow rate can be determined. This is provided that there is no chemical reaction between the two components and that they travel at the same average velocity. The system may be also used for monitoring changes in constituency of a single substance since the optimum value of H(1) depends upon this constituency.
Abouelwafa
M S
MS
Department of Electrical Engineering, The University of Calgary, Calgary, Alberta, Canada T2N 1N4.
Kendall
E J
EJ