Dispersed-phase velocities for gas-liquid vertical slug and dispersed-bubbles flows using an ultrasonic cross-correlation technique

There is a consensus in the oil industry that multiphase flow meters (MFMs) can bring various benefits to the oil industry. MFMs would reduce the minimum space and weight requirements of the platforms as they would eliminate the separating tanks and the interconnection pipes. One of the important variables to MFMs is the dispersed-phase velocity that is a closure relationship to mechanistic models. In this context, this paper studied the use of the ultrasonic cross-correlation technique based on the energies of the reflected pulses to estimate the dispersed-phase velocities for the dispersed-bubbles and the slug flow patterns. The experiments were done in a vertical two-phase liquid-gas flow pipe, with superficial liquid and gas velocities ranging from 0.5 to 3.9m/s and 0.1 to 3.7m/s, respectively. Also, the results were compared with image analysis and mechanistic models. For dispersed-bubbles flows, the relative deviation from the mixture velocities was less than 20%. For slug flows, the relative deviations from the images were less than 15%.