Modeling erosion process in elbows of petroleum pipelines using large eddy simulation

Elbows are widely used in piping systems to change the direction of flow. However, it is also extremely susceptible to erosive damage, which may lead to the leakage of petroleum and gas pipelines. Therefore, revealing the erosion process and accurately predicting erosion rate are of great importance to pipeline safety. In this study, the unsteady slurry erosion process in the 90° elbow is investigated numerically using LES Eulerian-Lagrangian methodology. The Large eddy simulation (LES) is coupled with Lagrangian particle tracking to simulate slurry flow and erosion process in elbows. The erosion prediction model is validated using experimental data before investigating the unsteady erosion process in elbows with different radius. The results show that the unsteady secondary flow can be precisely captured using LES and thus the prediction accuracy of the fluid flow velocities and turbulent intensities are improved by this model comparing to RANS. The particles movement coupled with the unsteady secondary flow and boundary separation in elbows with different radius can be successfully revealed using this methodology. The LES Eulerian-Langragian erosion model presented is helpful to understand the flow and slurry erosion in elbows and improve the accuracy of the CFD-based prediction of slurry erosion rate.