The use of Multiphase flowmeters in the oil and gas industry has increased significantly in recent years. The technology is now widely utilised subsea for well optimisation and reservoir management with the drive in development toward use for fiscal allocation.
Currently, the lack of an established reference network, guidelines and standards – whereby the metering technology can be reliably evaluated and/or verified for their applications – is inhibiting further development. In addition, the intrinsic complexities associated with multiphase and multi-component mixtures result in a wide variation in flow patterns developing, including challenging slugging conditions which must be detected in order to avoid flow assurance issues and catastrophic damage to processing equipment. The impact of challenging flow regimes on metering performance must also be accounted for through further research and development.
This paper reviews the current theoretical methods for the determination of flow patterns as a function of field variables such as pressure, temperature, component fluid properties and velocities. Established flow pattern maps presented in the literature and commonly used in industry are evaluated using experimental data from NEL's multiphase flow facility.
The development of flow pattern maps and flow visualisation techniques is a key part in the development of a much needed reference network for multiphase flow metrology. This work is part of a wider €3M project with support from the EU, National Measurement Institutes, Universities, Operators, Multiphase Flow Laboratories, Vendors and Regulators.