Numerical Analysis of Local Scour and Protection of a Single Pile Around a Seabed Under Solitary Wave and Current

Abstract

A numerical simulation is conducted to investigate the local scour of the seabed around the pile under the actions of both solitary waves and currents. By solving the N-S equations enclosed by the RNG k-ε turbulence model, the change of the flow field around the pile is simulated accurately. The sediment transport model considers all the sediment transport processes including entrainment, suspended load transport, deposition, and bed-load transport. For the slope seabed, the influence of gravity on the sediment particles is considered, and the shields parameter is modified. The accuracy of the model is verified by comparing the numerical results with the experimental data. Besides, the process of scour development at different wave heights is investigated in detail. The effect of pile foundation protection layer on scour is preliminarily studied. The results show that the combined solitary wave-current conditions have a significant effect on the scour depth around the pile than the current-only or wave-only. The scour depth around the pile on the inclined seabed is larger than that of the horizontal seabed. The setting of protection layer can effectively reduce the local scour depth around the pile. In addition, the particle size of the protective layer has a great influence on the protective effect.

Keywords

• monopile
• scour
• solitary wave
• current
• scour protection