Development of an analytical model for predicting the wet collapse pressure of curved flexible risers

OCEAN ENGINEERING

卷:232

Article

Li, Xiao¹  Jiang, Xiaoli¹  Hopman, Hans¹ 

[1] Delft Univ Technol, Dept Maritime & Transport Technol, Delft, Netherlands

关键词: Flexible pipes;    Curvature effect;    Collapse behaviors;    Wet collapse;    Analytical solution;   

DOI  :  10.1016/j.oceaneng.2021.109132

来源: Elsevier

【 摘 要 】

Flexible risers are designed with strong anti-collapse capacities which enable them to operate in deep-water reservoirs. However, this anti-collapse capacity is susceptible to the pipe curvature in the flooded annulus condition. For the curved riser sections within the touch-down zone, significant reduction of collapse capacity can occur once their external sheaths are worn out by the seabed, resulting in the so-called wet collapse''. Mostly, wet collapse studies of curved flexible risers are performed through costly numerical simulations since there are no alternative analytical approaches. In view of it, this work presents an analytical model for predicting the wet collapse pressure of curved flexible risers. The analytical model is developed based on a spring-supported arch model that from our previous work, which is able to take the curvature-induced factors into account. With the stability theories of arched structures, the wet collapse pressure of curved flexible risers can be solved. To verify this analytical model, 3D full FE models are employed. The critical collapse pressures predicted by these two kinds of approach are in good agreement, indicating this proposed analytical model can be an useful tool to facilitate the collapse analysis in pipe design stage.

【 授权许可】

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