ABSTRACT The continuing need for in-situ measurements of physical properties of wastes contained within many high-level radioactive waste tanks within the Hanford Site has initiated experimental and theoretical investigations of candidate measurement methods. This paper describes experiments performed with acoustic wave-guide sensors. This technology has potential application at the Hanford Site for in-situ measurements of density, viscosity, and temperature of liquid wastes. Waveguides of both circular and rectangular geometry were used in these studies for determination of the densities and viscosities of various fluids. The flight time of a torsional pulse through the sensing region of the wave-guide forms the measured quantity. The flight time depends on the velocity of the wave through the sensing region of the wave-guide, and this velocity in turn depends upon the properties of the fluid in contact with the wave-guide. We performed experiments with 15 different fluids, most of which were single-phase Newtonian fluids. However, three of the fluids were particle-liquid mixtures, and one of these was non-Newtonian in behavior. Most of the wastes held in Hanford tanks contain high solids content. The results of our experiments showed that acoustic wave-guides were well suited for measurements in most Newtonian fluids, in agreement with earlier research presented in the literature. However, results for two-phase Newtonian fluids containing particles indicate that, in our case, the wave-guides responded primarily to the background fluid rather than the mixture. Very poor results were obtained with the non-Newtonian fluid. In addition, there was a class of fluids, which serve the community as viscosity standards, for which viscosities determined with torsional wave-guides were in disagreement with viscosities obtained with standard viscometers.
1999 IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control Vol. 46, pp. 536-548, 1999
© 1999, by The Institute of Electrical and Electronics Engineers, Inc. All rights reserved.