Multiphase flow regime identification by multibeam gamma-ray densitometry

Multibeam gamma-ray densitometry can be applied to identify flow regimes in hydrocarbon multiphase oil, water and gas pipe flows. The acquired flow regime information can be used for improved measurement accuracy on gas volume fractions, and as complementary information for other types of flow instrumentation, in order to enhance their accuracy. The work presented in this paper includes both theoretical calculations and experimental work on three-phase flow using multibeam gamma-ray densitometry. It is demonstrated that a fan beam geometry with one radiation source and several collimated detectors is sufficient to provide information on the liquid-gas distribution of the pipe flow. In order to perform testing on deviated multiphase oil, water and gas flows, a special tilt section was designed and built. Several different flow regimes were successfully identified from the acquired experimental measurement data. The work presented in this paper was conducted as a part of a project aiming to develop technology for improved multiphase hydrocarbon metering, along with joint project partners Roxar Flow Measurements AS and Christian Michelsen Research AS.