Review of Core Annular Flow

With the increasing demand for heavy oil, core annular flow (CAF) is an economical method to transport heavy oil, and many researchers have explored the energy-saving aspects of the CAF method. This paper presents a review of CAF energy saving and factors affecting CAF energy saving. Among them, the energy saving of CAF mainly concerns the changes in pressure drop and drag reduction efficiency; the factors affecting the energy saving of CAF mainly concern the problem of stability, the issue of restarting the pipeline system, the impact of a nozzle, the impact of fouling on the flow in the pipe, and the problem of oil-water accumulation. The aim of this paper is to provide a reference for the practical application of CAF in heavy oil transportation.

Automated summary

This paper reviews the energy-saving aspects of core annular flow (CAF) and factors affecting CAF energy saving. The energy saving of CAF mainly concerns changes in pressure drop and drag reduction efficiency; factors affecting the energy saving of CAF mainly include stability, pipeline system restart, nozzle impact, fouling impact on flow, and oil-water accumulation. The aim of this paper is to provide a reference for the practical application of CAF in heavy oil transportation.