Numerical Simulation of Nearshore Submarine Pipeline Scour under Storm Surge Condition

摘要

Submarine pipelines are widely used to deliver oil and gas inoffshore petroleum engineering. Local scour can leads to thesuspension of pipelines, which can finally results in the pipelinevibration and damage, even oil leaking and marine pollution.Previous research mainly focus on the scour under constant seaconditions, while under variable sea conditions such as stormsurges are less studied. Typhoon storm features fast-moving,short duration and intensive wave actions, which can lead toviolent seabed sediment movements usually. Based on thecharacteristics of waves during typhoon storms passing SouthChina Sea, the idealized and simplified cases were generalizedwith typical wave parameters, including wave height, waveperiod, and their changeable rules during storm surge passage.A Navier-Stokes solver FLOW-3D was used to establish 2-Dnumerical simulations under wave conditions mentioned above,following a procedure of wave height increasing, staying stable,and getting lower gradually, following the rules of a typhoonpassage. This paper aims to analyze the submarine pipelinescour rules under extreme sea conditions aforementioned, andprovide scientific guidance for submarine pipeline design andprotection in the near shore area.