Numerical study on local scour characteristics around submarine pipelines in the Yellow River Delta silty sandy soil under waves and currents  

作　　者：Peng Yu Ruigeng Hu Jike Zhang Qi Yang Jieru Zhao Lei Cao Chenghao Zhu 

机构地区：[1]Key Laboratory of Geological Safety of Coastal Urban Underground Space,Ministry of Natural Resources,Qingdao,China [2]Qingdao Geo-Engineering Surveying Institute(Qingdao Geological Exploration Development Bureau),Qingdao,China [3]Sinopec Petroleum Engineering Corporation,Dongying,China [4]State Key Laboratory of Hydroscience and Engineering,Tsinghua University,Beijing,China [5]Department Civil and Environmental Engineering,Politecnico di Milano,Milan,Italy [6]College of Environmental Science and Engineering,Ocean University of China,Qingdao,China

出　　处：《Deep Underground Science and Engineering》2024年第2期182-196,共15页深地科学（英文）

基　　金：China Postdoctoral Science Foundation,Grant/Award Number:2023M731999;National Natural Science Foundation of China,Grant/Award Number:52301326。

摘　　要：Due to their high reliability and cost-efficiency,submarine pipelines are widely used in offshore oil and gas resource engineering.Due to the interaction of waves,currents,seabed,and pipeline structures,the soil around submarine pipelines is prone to local scour,severely affecting their operational safety.With the Yellow River Delta as the research area and based on the renormalized group(RNG)k-εturbulence model and Stokes fifth-order wave theory,this study solves the Navier-Stokes(N-S)equation using the finite difference method.The volume of fluid(VOF)method is used to describe the fluid-free surface,and a threedimensional numerical model of currents and waves-submarine pipeline-silty sandy seabed is established.The rationality of the numerical model is verified using a self-built waveflow flume.On this basis,in this study,the local scour development and characteristics of submarine pipelines in the Yellow River Delta silty sandy seabed in the prototype environment are explored and the influence of the presence of pipelines on hydrodynamic features such as surrounding flow field,shear stress,and turbulence intensity is analyzed.The results indicate that(1)local scour around submarine pipelines can be divided into three stages:rapid scour,slow scour,and stable scour.The maximum scour depth occurs directly below the pipeline,and the shape of the scour pits is asymmetric.(2)As the water depth decreases and the pipeline suspension height increases,the scour becomes more intense.(3)When currents go through a pipeline,a clear stagnation point is formed in front of the pipeline,and the flow velocity is positively correlated with the depth of scour.This study can provide a valuable reference for the protection of submarine pipelines in this area.

关 键 词：local scour numerical simulation submarine pipelines Yellow River Delta 

分 类 号：P756.2[天文地球—海洋科学]