A Noninvasive Solution for Multiphase Flow Analysis in Pipelines Based on High-Resolution Distributed Acoustic Sensing (HR-DAS)

Abstract Multiphase flow in pipelines presents significant challenges, particularly in the petroleum and oil industries, where the presence of air, gas, and solid particles in liquid pipelines can lead to severe operational inefficiencies, safety hazards, severe vibrations and catastrophic failures. Traditional multiphase flow metering (MFM) methods are mostly invasive and expensive and often fall short of mapping such complex flow conditions along the entire pipeline. This study aims to address these critical issues by exploring the capabilities of a high-resolution distributed acoustic sensing (HR-DAS) system in detecting and characterizing two-phase flows under controlled conditions. A custom-designed PVC flow loop was developed to simulate various flow scenarios, including single-phase and two-phase flows with gas injection. The HR-DAS system demonstrated its potential to accurately identify two-phase flow regimes in the pipeline. Frequency analysis revealed distinctive shifts and damping effects associated with two-phase flow, providing critical insights into fluid composition and transient events like a pocket of air in a plug flow. The data collected by the HR-DAS system were juxtaposed with the accelerometer data attached to the pipe for validation. These findings highlight the novel application of the HR-DAS system for real-time multiphase flow analysis in pipelines, offering a high-resolution, multi-point, noninvasive alternative to conventional metrology techniques. Unlike existing approaches, this study demonstrates HR-DAS’s ability to map flow dynamics and detect phase transitions continuously along the pipelines without modifying the pipeline with invasive probes.