Mechanism of local scour around submarine pipelines based on numerical simulation of turbulence model

作     者：L Lin1*, LI Yucheng1,3, CHEN Bing21. State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology, Dalian 116024, China2. School of Civil and Hydraulic Engineering, Dalian University of Technology, Dalian 116024, China3. R&D center of civil Engineering Technology, Dalian University, Dalian 116622, ChinaReceived 20 July 2005 accepted 14 December 2005 

作者机构：State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 China RandD Center of Civil Engineering Technology Dalian University Dalian 116622 China School of Civil and Hydraulic Engineering Dalian University of Technology Dalian 116024 China 

出 版 物：《Acta Oceanologica Sinica》 (海洋学报(英文版))

年 卷 期：2006年第25卷第2期

页      面：142-152页

核心收录：

学科分类：0710[理学-生物学] 081505[工学-港口、海岸及近海工程] 0908[农学-水产] 0707[理学-海洋科学] 08[工学] 0815[工学-水利工程] 0824[工学-船舶与海洋工程] 0814[工学-土木工程] 082401[工学-船舶与海洋结构物设计制造] 

主　　题：submarine pipeline mechanism of local scour renormalized group turbulence model large eddy simulation piping 

摘      要：The mechanism of local scour around submarine pipelines is studied numerically based on a renormalized group (RNG) turbulence model. To validate the numerical model, the equilibrium profiles of local scour for two cases are simulated and compared with the experimental data. It shows that the RNG turbulence model can give an appropriate prediction for the configuration of equilibrium scour hole, and it is applicable to this situation. The local scour mechanism around submarine pipelines including the flow structure, shear stress distribution and pressure field is then analyzed and compared with experiments. For further comparison and validation, especially for the flow structure, a numerical calculation employing the large eddy simulation (LES) is also conducted. The numerical results of RNG demonstrate that the critical factor governing the equilibrium profile is the seabed shear stress distribution in the case of bed load sediment transport, and the two-equation RNG turbulence model coupled with the law of wall is capable of giving a satisfying estimation for the bed shear stress. Moreover, the piping phenomena due to the great difference of pressure between the upstream and downstream parts of pipelines and the vortex structure around submarine pipelines are also simulated successfully, which are believed to be the important factor that lead to the onset of local scour.