VOLUME FRACTION MEASUREMENTS OF WATER-IN-OIL BY AN ULTRASONIC TECHNIQUE

An ultrasonic technique developed previously is,extended for measurements of volume fractions of water in oil at low phase fractions and for long path lengths. The technique is applied on a number of stirred vessels of 10-cm diameter and 10-, 20-, 30-, and 50-cm length and on a continuous-flow apparatus. Experiments for a 1-m-length column suggest meaningful measurements can be obtained for this length as well. Results demonstrate the utility of the ultrasonic technique to measure volume fractions as low as 0.005. The, travel time of sound through the liquid dispersion permits the estimation of the volume fraction of the two phases by a linear model which considers sound reflection through the drop and refraction on the drop interface. This model works well for volume fractions higher than 5%. An empirical model is applied for volume fractions lower than 5%. The relative error in the measurements is of the order of 10%.