Two-Phase Swirling Flow and Gas Hydrate Particle Deposition Behavior in Bending Pipelines

The present study employs numerical simulation to analyze the behavior of gas hydrate particles in bending pipelines, focusing on the influence of swirl flow on particle deposition under varying bending angles, pipe-to-diameter ratios, Reynolds numbers, and twist rates. Results indicate that larger bending angles, smaller twist rates, and higher Reynolds numbers produce stronger swirl flows at pipe entry and sustain higher swirl numbers along the pipeline. Conversely, larger pipe-to-diameter ratios result in greater swirl number variations, slower attenuation, and weaker outflow. Moreover, the phenomenon of hydrate particle deposition is more serious in the straight pipe section. Particle retention at the pipe outlet is 1.5 times higher than in the bending section. The bent pipe is more conducive to the flow of particles. For instance, with a bend rate increasing from 1 to 4, the swirl number decreases by 57.49%. Additionally, the deposition rate of particles is reduced at higher Reynolds numbers, with rates falling below 1% at a Reynolds number of 20,000. These findings highlight the need to optimize swirl flow parameters to reduce hydrate deposition, preventing blockages and improving pipeline safety in industrial applications.