Critical conditions of local scour below submarine pipelines under wave action

被引：0
作者：
Zhang, Zhiyong [1 ,2 ]
Liu, Guangsheng [1 ]
Zeng, Jian [1 ]
机构：
[1] Key Laboratory of Estuary and Coast of Zhejiang Province, Zhejiang Institute of Hydraulics and Estuary, Hangzhou
[2] College of Civil Engineering and Architecture, Zhejiang University, Hangzhou
来源：
Harbin Gongcheng Daxue Xuebao/Journal of Harbin Engineering University | 2015年 / 36卷 / 11期
关键词：
Boundary wave generation method; Critical condition; Porous media; Scour; Submarine pipe line; VOF method;
D O I：
10.11990/jheu.201406010
中图分类号：
学科分类号：
摘要：
It is absolutely essential to study scour onset beneath submarine pipelines for pipeline protection. In this paper a new hydrodynamic-seepage fields coupled numerical model was developed, assuming that the sandy bed was porous media. Sand flow resistance in a sandy bed was implemented by adding an adequate source in the momentum equation. The numerical model was verified by numerical experiments, and on this basis, the hydrodynamic-seepage fields around submarine pipeline under wave action were solved based on the boundary wave generation and volume of fluid (VOF) methods. The effects of wave KC and relative buried depth e/D on pressure difference between upstream and downstream points of pipe were analyzed respectively and the hydraulic gradient at the seepage exit was studied. In addition, the dimensionless critical velocities of critical condition in cases of different KC and e/D were obtained. It was found that the pressure difference decreases with increasing KC and relative buried depth e/D while the dimensionless critical velocity of critical condition increases with increasing KC and e/D. Also, an empirical fitted formula to calculate the critical condition for scour below submarine pipelines under wave action is given, which is significant foreffective protection of submarine pipelines in practical engineering projects. © 2015, Editorial Department of Journal of HEU. All right reserved.
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页码：1433 / 1437
页数：4
相关论文
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