Flow characteristics of solid-liquid two-phase flow in flexible vibrating pipelines

Abstract

Vibration of flexible pipelines in the marine environment affects the flow characteristics of the transported materials inside the pipelines, which is related to transportation efficiency and energy consumption, thereby necessitating further investigation. In this study, the flow characteristics of particle-liquid two-phase flow transported upward in flexible pipelines are investigated based on the computational fluid dynamics-discrete element method (CFD-DEM). Typical forms of vibration including standing wave vibration and traveling wave vibration are employed and compared with a stationary pipeline. Results reveal that particles in the upward-traveling-wave vibrating pipeline still mainly distribute in the middle of the pipeline, while particles in the standing-wave vibrating pipeline exhibit periodic transverse aggregation near the pipe wall, and the fluctuations of particle concentration and particle z-direction velocity over time in each cross section of the pipeline are more obviously suppressed. When the propagation direction of the vibration wave changes from the same direction as the particle transport to static and then to the opposite direction, its hindering and regulating effect on the particles gradually increases, and the pipeline pressure drop gradually decreases.