Investigation on the Local Scour Beneath Piggyback Pipelines Under Clear-Water Conditions  

作　　者：Sahar ASRARI Habib HAKIMZADEH Nazila KARDAN 

机构地区：[1]Faculty of Civil Engineering,Sahand University of Technology,Sahand,Iran [2]Department of Civil Engineering,Azarbaijan Shahid Madani University,Tabriz,Iran

出　　处：《China Ocean Engineering》2021年第3期422-431,共10页中国海洋工程（英文版）

摘　　要：A piggyback pipeline consists of two pipes such that the secondary line rides on the main pipe with a fixed distance between two pipes in length.The novel strategy is utilized in offshore areas instead of a single flow line.In this regard,there are only a handful of experimental and numerical studies investigating the effect of scour below a piggyback pipeline under steady current.Hence,this study focuses on examining the influential factors on scouring due to steady current including the pipe diameter and the gap between pipes through numerical simulations and experimental tests.Accordingly,at the first phase of the research,a single pipe was established and tested in laboratory to compare the results with those of an empirical equation.After finishing experimental verifications,piggyback pipelines were also assembled to study the scouring under steady current conditions.It was concluded that by increasing the gap distance between the pipes,the maximum scour depth decreases;however,an increase in the small pipe’s diameter results in a larger maximum scour depth.Secondly,numerical simulations were carried out using the FLOW-3D software which was found to be a suitable tool for the numerical investigation of this study.Finally,the numerical results have been compared with the corresponding experimental data and a relatively good agreement was achieved between them.

关 键 词：local scour piggyback pipeline scour depth numerical simulation 

分 类 号：P756.2[天文地球—海洋科学]