Self-Burial Structure of the Pipeline with a Spoiler on Seabed

If a spoiler was attached to the pipeline investigated in a previous study, a strong flow and vortex at the lower part caused scouring and thus an asymmetric pressure distribution, which assisted in the analysis of the self-burial structure where a down force was applied to the pipe. However, only the fluid-pipe interaction was considered, excluding the medium (seabed), when practically burying the pipeline. Thus, this study applied a numerical model (LES-WASS-2D) to directly analyze the non-linear interactions among the fluid, pipe, and seabed in order to perform numerical simulations of a pipeline with a spoiler installed on the seabed. This allowed the self-burial mechanism of a pipeline with a spoiler to be analyzed in the same context as the previous study that considered only the fluid-pipe interaction. However, when a pipeline was installed on the seabed, a strong flow and vortex were found at the front of the bottom, and a spoiler accelerated the fluid resistances. This hydraulic phenomenon will reinforce the scouring and down force on the pipeline. In the general consideration of the numerical analysis results by the specifications and arrangements of the spoiler, a pipeline with a spoiler was found to be the most effective for the self-burial function. Received 16 February 2016, revised 14 June 2016, accepted 18 August 2016 Corresponding author Dong-Soo Hur: +82-55-641-3150, dshur@gnu.ac.kr ◯c 2016, The Korean Society of Ocean Engineers

[1]  Jianping Zhao,et al.  CFD Numerical Simulation of the Submarine Pipeline With a Spoiler , 2009 .

[2]  J. Brackbill,et al.  A continuum method for modeling surface tension , 1992 .

[3]  P. Moin,et al.  A dynamic subgrid‐scale eddy viscosity model , 1990 .

[4]  J. Smagorinsky,et al.  GENERAL CIRCULATION EXPERIMENTS WITH THE PRIMITIVE EQUATIONS , 1963 .

[5]  Dongfang Liang,et al.  Numerical modeling of flow and scour below a pipeline in currents: Part II. Scour simulation , 2005 .

[6]  Hongjun Zhu,et al.  Numerical simulation of flow around a submarine pipe with a spoiler and current-induced scour beneath the pipe , 2013 .

[7]  C. H. Huisbergen.  Stimulated Self-Burial of Submarine Pipelines , 1984 .

[8]  Y. M. Chiew.  Effect of Spoilers on Wave-Induced Scour at Submarine Pipelines , 1993 .

[9]  Hyo Jae Jo,et al.  Numerical Analysis on Self-Burial Mechanism of Submarine Pipeline with Spoiler under Steady Flow , 2016 .

[10]  C.A.M. Barendse.  Hydrodynamic forces on a near-bed offshore pipeline with spoiler, during the selfburying process , 1988 .

[11]  H. G. Wind,et al.  Numerical modelling of erosion and sedimentation around offshore pipelines , 1990 .

[12]  Numerical simulation of oscillatory flow around submarine pipelines , 2016 .

[13]  Dong-Soo Hur,et al.  Effect of the Slope Gradient of Submerged Breakwaters on Wave Energy Dissipation , 2011 .

[14]  P. Zamankhan.  Analysis of Submarine Pipeline Scour Using Large-Eddy Simulation of Dense Particle-Liquid Flows , 2009 .

[15]  Jacob H. Masliyah,et al.  Non-linear flows in porous media , 1999 .

[16]  Yakun Guo,et al.  Calculation and experiment on scour depth for submarine pipeline with a spoiler , 2012 .

[17]  Yan Han.  Study on the Submarine Pipeline with Flexible Spoilers , 2012 .

[18]  D. Lilly,et al.  A proposed modification of the Germano subgrid‐scale closure method , 1992 .

[19]  Ahmet Alper Öner.  The flow around a pipeline with a spoiler , 2010 .

[20]  Liang Cheng,et al.  Modelling of flow around a near-bed pipeline with a spoiler , 2003 .

[21]  S. Ergun.  Fluid flow through packed columns , 1952 .

[22]  C H Hulsbergen,et al.  Effect of Spoilers on Submarine Pipeline Stability , 1989 .