Browse > Article
http://dx.doi.org/10.12989/ose.2015.5.2.077

A finite element analysis for unbonded flexible risers under bending loads  

Xiqia, Chen (Tianjin Branch, CNOOC Ltd.)
Shixiao, Fu (State Key Laboratory of Ocean Engineering, Shanghai Jiao Tong University)
Yun, Gao (State Key Laboratory of Oil and Gas Reservoir Geology and Exploration, Southwest Petroleum University)
Xiaying, Du (Tianjin Branch, CNOOC Ltd.)
Publication Information
Ocean Systems Engineering / v.5, no.2, 2015 , pp. 77-89 More about this Journal
Abstract
As the exploitation of oil and gas resources advances into deeper waters and harsher environments, the design and analysis of the flexible risers has become the research focus in the offshore engineering filed. Due to the complexity of the components and the sliding between the adjacent layers, the bending response of the flexible risers is highly non-linear. This paper presents the finite element analysis of the flexible risers under bending loads. The detailed finite element model of the flexible riser is established in ABAQUS software. This finite element model incorporates all the fine details of the riser to accurately predict its nonlinear structural behavior. Based on the finite element model, the bending moment-curvature relationships of a flexible riser under various axisymmetric loads have been investigated. The results have been compared with the analytical ones obtained from the literature and good agreements have been found. Moreover, the stress of the tendon armors has been studied. The non-linear relationship between the armor tendons' stress and the bending loads has been obtained.
Keywords
flexible risers; finite element model; non-linear; bending loads; axisymmetric loads; stress;
Citations & Related Records
Times Cited By KSCI : 3  (Citation Analysis)
연도 인용수 순위
1 Alfano, G., Bahtui, A. and Bahai, H. (2009), "Numerical derivation of constitutive models for un-bonded flexible risers", Int. J. Mech. Sci., 51(4), 295-304.   DOI
2 Bahtui, A., Alfano, G., Bahai, H. and Hosseini-Kordkheili, S.A. (2010), "On the multi-scale computation of un-bonded flexible risers", Eng. Struct., 32(8), 2287-2299.   DOI
3 Bahtuim A., Bahai, H. and Alfano, G. (2008a), "A finite element analysis for unbonded flexible risers under axial tension", Proceedings of the 27th International Conference on Offshore Mechanics and Arctic Engineering, Estoril, Portugal.
4 Bahtui, A., Bahai, H. and Alfano, G. (2008b), "A finite element analysis for unbonded flexible risers under torsion", J. Offshore Mech. Arct., 130(4), 041301.   DOI
5 de Sousa, J.R.M., Magluta, C., Roitman, N., Ellwanger, G.B., Lima, E.C.P. and Papaleo, A. (2009), "On the response of flexible risers to loads imposed by hydraulic collars", Appl. Ocean Res., 31, 157-170.   DOI
6 Do, K.D. (2011), "Global stabilization of three-dimensional flexible marine risers by boundary control", Ocean Syst. Eng., 1(2), 171-194.   DOI
7 Dong, L., Huang, Y., Zhang, Q. and Liu, G. (2013), "An theoretical model to predict the bending behavior of unbonded flexible risers", J. Ship Res., 57(3), 171-177.   DOI
8 Eom, T.S., Kim, M.H., Bae, Y.H. and Cifuentes, C. (2014), "Local dynamic buckling of FPSO steel catenary riser by coupled time-domain simulations", Ocean Syst. Eng., 4(3), 215-241.   DOI
9 Huang, H., Zhang, J. and Zhu, L. (2013), "Numerical model of a tensioner system and riser guide", Ocean Syst. Eng., 3(4),257-273.   DOI
10 Merino, H.E.M., Sousa, J.R.M., Magluta, C. and Roitman, N. (2010), "Numerical and experimental study of a flexible pipe under torsion", Proceedings of the 29th International Conference on Offshore Mechanics and Arctic Engineering, Shanghai, China.
11 Ren, S.F., Tang, W.Y. and Guo, J.T. (2014), "Behavior of unbonded flexible risers subject to axial tension", China Ocean Eng., 28(2), 249-258.   DOI
12 Song, L.J. (2013), The overall response characteristics research and fatigue analysis of the lazy-wave flexible riser, Mater Dissertation, Shanghai Jiao Tong university, Shanghai, China.
13 Saevik, S. and Berge, S. (1995), "Fatigue testing and theoretical studies of two 4 in. flexible pipes", Eng. Struct., 17(4), 276-292.   DOI
14 Saevik, S. and Bruaseth, S. (2005), "Theoretical and experimental studies of the axisymmetric behaviour of complex umbilical cross-sections", Appl. Ocean Res., 27(2), 97-106.   DOI
15 Saevik, S. and Gjosteen, J.K.O. (2012), "Strength analysis modelling of flexible umbilical members for marine structures", J. Appl. Math., 2012(985349).