Flow pattern evolution and flow-induced vibration response in multiphase flow within an M-shaped subsea jumper

Abstract

The subsea jumper, a crucial pipeline connector facilitating liquid transport between underwater structures, experiences dynamic alterations in flow direction, rate, and phase volumes owing to its distinctive design. These complex flow characteristics can trigger flow-induced vibrations, potentially causing fatigue damage to the jumper. This paper explores the multiphase flow patterns (oil, gas, and water) in a rigid M-shaped subsea jumper under varied mixing velocities (2–4 m/s) and different volume fractions of each phase (0.1–0.7). It analyzes the factors influencing structural vibration response. The findings reveal diverse flow patterns within the jumper, each exhibiting distinct characteristics based on flow parameters. Concurrently, spatiotemporal oscillations from fluid dynamics impact each bend. Pressure on jumper walls gradually diminishes with changing flow direction. Furthermore, the study performs structural modal and frequency domain analyses of pulsating pressure to evaluate potential resonance conditions. The results of this paper contribute to a deeper understanding of the multiphase flow characteristics in jumpers, offering valuable insights to enhance the reliability of underwater oil and gas production.