Numerical Simulation of Side Branch Erosion Resistant Elbow Based on CFD-DPM

As a critical component in the marine pipeline system, the elbows are significantly more susceptible to erosion damage than the straight pipe sections. A novel elbow structure integrated with auxiliary bypass channels are designed to improve its erosion resistance and prolong its service life. Numerical simulations of the elbow erosion process by the liquid-solid two-phase flow are performed using the CFD-DPM approach. The erosion patterns of a conventional elbow and the proposed anti-erosion elbow are compared under varying flow velocities and sand concentrations. Furthermore, the trajectories of solid particles within both elbow types are analyzed and the anti-erosion mechanism of the proposed anti-erosion elbow is investigated. Results indicate that the proposed anti-erosion elbow structure generates a teardrop-shaped low-velocity zone at the outer wall of the elbow outlet. The fluid within this zone substantially attenuates the kinetic energy of particles impacting the wall surface. Moreover, the erosion mitigation effect becomes more pronounced with increasing flow velocity. This design can effectively mitigate the solid particle erosion damage at the elbow, thereby extending its operational lifespan.