CFD NUMERICAL SIMULATION OF THE SUBMARINE PIPELINE WITH SPOILER

Submarine pipeline is one of the most important oil transportation components, pipeline failure due to over-span is the most serious failure mechanism. There are four reasons of pipeline span formation, including erosion of seabed, bumpy seabed, submarine pipeline climbing slope, and pipeline ascending to offshore platform. The Hangzhou Bay submarine pipeline is the most important subproject of the Yong-Hu-Ning network, and it is also the biggest long-distance pipeline for crude oil in China. Due to the dynamic nature of Hangzhou Bay, including high tides and high current amplified by the shallow waters, a self-burial method was selected as the best solution. By increasing the velocity of die stream between the pipeline and the seabed, shear stress on the seabed was enhanced. This localized increase in shear stress causes the seabed under the pipe to erode more quickie and facilitates self-burial of the pipe. To facilitate self-burial, a non-metallic vertical fin is fastened to the top of the pipeline. In this paper flow around a pipeline with and without a spoiler near a smooth wall is Simulated with FLUENT version 6.1. The influences of the spoiler on pressure coefficient, lift coefficient, shear stress on the wall, as well as velocity profile are investigated. It is indicated that the coefficients for Drag and Inertia are increased with the application of the spoiler. The lift coefficient is reversed with the application of the spoiler increases the stability of the pipeline resulting in the reduction of the required coating weight.