An experimental study on scour around the submarine pipeline with spoilers under wave conditions

With the development of offshore oil and gas fields, research on the protection of submarine pipeline which is one of the most important aspects of an offshore oil field exploitation system, becomes more important. In this paper, a series of experiments has been conducted to compare the effectiveness of rigid spoilers installed on the top of the pipeline with the effectiveness of flexible spoilers installed on the bottom of the pipeline and in an attempt to find a better way to protect the pipeline from floating even fracturing. Scours depth and width around the pipeline with different lengths of spoilers were measured and analyzed. It was found that the scour depth reached the maximum value 0.5D when the flexible spoiler length attained the critical value of L=0.35D, which was much bigger than it with a rigid spoiler, furthermore, the scour width was narrower than the rigid one. Therefore it is a better way to make the pipeline self-burial.