Two-Phase Simulation of Coastal Current-Induced Scour around Submarine Pipelines

Kazeminezhad, M.H. and Yeganeh-Bakhtiary, A., 2011. Two-phase simulation of coastal current-induced scour around submarine pipeline. Journal of Coastal Research, SI 64 (Proceedings of the 11th International Coastal Symposium), ��� – ���. Szczecin, Poland, ISSN 0749-0208 Continuous scouring around submarine pipelines is of great importance because of its effects on the structural stability of pipelines. In this study, current-induced scour around submarine pipeline was numerically investigated. An Euler-Euler two-phase model was developed to simulate the early stages of scouring. The model solved time averaged continuity and momentum equations for fluid and sediment phases with a modified k-e turbulence closure for the fluid phase. The model accounted for the interphase momentum exchange by considering drag and lift forces; while the particle-particle interaction was considered via intergranular stresses. The model was employed in simulation of tunnel erosion stage of scouring around submarine pipeline laid on an erodible bed. It was found that the scour depth just below the pipe developes quickly at early stages of scour. Results indicated that the mean gap flow velocity increased as the scour depth increased up to a certain value. Comparison between measured and simulated bed profile revealed that the developed model performs well in simulation of tunnel erosion scour around pipeline.

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