Study on Interference of the Dynamic Unbonded Flexible Riser

Abstract

Abstract:

The dynamic unbonded flexible riser which is the key equipment in the offshore petroleum industry owns some advantages such as easy installation, high reliability and high anti-fatigue property. The dynamic unbonded flexible riser is manufactured by twining with polymer layers and steel tape layers. The section stiffness of flexible riser is in the relative low level compared with soild steel pipe, and it is easy to move when facing to the current, so the flexible riser configuration must be specially designed to avoid the interaction between the risers and mooring lines. We use the Huse wake model and finite element method (FEM) to analyze the flexible riser and mooring line in the South China Sea environment, meanwhile perform the sensitivity analyses of riser section stiffness, pipe flow density and drag coefficient. Finally, some engneering meaningful conclusions are given.

Key words: flexible riser, interaction analysis, drag coefficient, Huse wake model

CLC Number:

TE973.92

Wei-wei ZHOU, Yong SHA, Jing CAO. Study on Interference of the Dynamic Unbonded Flexible Riser[J]. Ocean Engineering Equipment and Technology, 2014, 1(1): 35-41.

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参数	数值
水深/m	300
立管长度/m	839
触底段长度/m	205
外径/m	0.4182
内径/m	0.2032
弯曲刚度/(kN·m²)	472
轴向刚度/MN	660
扭转刚度/(kN·m²)	7391
许用弯曲曲率/m^-1	0.25
单位长度质量/(kg·m^-1)	218
拖曳力系数	1.05
海生物附着(0~20 m水深)/mm	50
海生物附着(20~300 m水深)/mm	20
输送介质密度/(kg·m^-3)	920
k₁	0.25
k₂	1.0
k₃	0.693

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