Non-intrusive identification and characterization of two-phase flow in horizontal pipes using broadband induced vibration

Gas–liquid two-phase flows in horizontal pipelines generate complex dynamic loads on the pipe wall due to the interaction between evolving flow structures and the pipe. These interactions often produce broadband vibration signatures whose physical origin remains poorly understood. This work proposes an experimental investigation on two-phase flow induced vibration in horizontal pipes. The relationship between characteristic flow structures and the resulting vibration response of the pipe is explored by the coupling between acoustic, elastic, and pressure waves. This is done using data from an experimental dataset using a test section equipped with accelerometers, piezoelectric pressure sensors, void fraction sensors and a high-speed camera with synchronized measurements under different air/water flow conditions. Signal processing techniques are used to investigate the main features of the induced vibration in the pipe in a broad frequency band. Subsequently, the pipe’s excitation mechanisms are investigated, including the effects from the flow structures and the bubble size distribution, and it is shown that they can be identified from vibration measurements external to the pipe. These findings provide new insight into the physical mechanisms governing broadband flow-induced vibration in multiphase pipelines. Their potential for vibration-based monitoring approaches is shown by the proposed identification and characterization method. It stands out for being non-intrusive/non-invasive, cost-effective, and with great potential for industrial applications, enabling more reliable monitoring and control of industrial two-phase flow systems.