Numerical Simulation of Float-Over Installation for Offshore Platform

Abstract

In this paper, a numerical investigation of a float-over installation for an offshore platform is presented to verify the feasibility of the actual installation. The hydrodynamic performance of a T-barge is investigated in the frequency domain, and the coupled motions are analyzed in the time domain. We then compare with those of the model test and determine that the response amplitude operator and the time series agree quite well. The barge exhibits favorable hydrodynamic behavior in the considered sea state, and the equipment loads are allowable. The mooring system and sway fender forces are within the permissible range. Based on these results, we can verify that the actual installation of the offshore platform is feasible. We accurately simulated many important factors and effectively reduced the risk associated with the offshore installation, which is of great importance. As such, we demonstrate that the numerical simulation of the float-over installation for offshore platforms has practical engineering significance.

Keywords

Float-over installation / Offshore platform / T-barge / Model test / Mooring system / Fender collision force / Numerical simulation

References

[1] Chen MS, Eatock Taylor R, Choo YS. Time domain modeling of a dynamic impact oscillator under wave excitations. Ocean Eng, 2014, 76: 40-51

[2] Chen MS, Eatock Taylor R, Choo YS. Investigation of the complex dynamics of float-over deck installation based on a coupled heave-roll-pitch impact model. Ocean Eng, 2017, 137: 262-275

[3] Cummins W.E, 1962. The impulse response function and ship motions. Schiffstechnik, (09), 101–109

[4] Dai YS, Duan WY. Potential flow theory of ship motion in waves, 2008, China, Beijing: National Defense Industry Press

[5] Du XY. Searching for float-over installation of Nanpu35-2 CEP moudule. China Offshore Platform, 2007, 22(04): 39-43

[6] Fan M, Yi C, Bai XP, . Research and application of key technologies for float-over installation of large topside in China. China Offshore Oil Gas, 2013, 25(06): 98-100

[7] Geba KA, Welaya YMA, Lehet HW, . The hydrodynamic performance of a novel float-over installation. Ocean Eng, 2017, 133: 116-132

[8] Hamilton J, French R, Penman AD, 2008. Topsides and jacket modeling for float-over installation design. Offshore Technology Conference Paper, 5–8 may, Houston, Texas, USA, DOI: https://doi.org/10.4043/19227-MS

[9] Hu ZH, Li X, Zhao WH, Wu X. Nonlinear dynamics and impact load in float-over installation. Appl Ocean Res, 2017, 65: 60-78

[10] Liang X X, Zhang Y G, He M, et al, 2012. Application of MOSES software to offshore installation analysis for large jackets. Shipbuilding of China, Xiamen, 53(S2), 362–371

[11] Pessoa J, Fonseca N. Investigation of depth effects on the wave exciting low frequency drift forces different approximation methods. Appl Ocean Res, 2013, 42: 182-199

[12] Seij M, Groot HD, 2007. State of the art in float-overs. Offshore Technology Conference, 30 April-3 May, Houston, Texas, U.S.A. DOI: https://doi.org/10.4043/19072-MS

[13] Sun L, Eatock Taylor R, Choo YS. Muli-body dynamic analysis of float-over installations. Ocean Eng, 2012, 51: 1-15

[14] Tahar A, Halkyard J, Steen A, Finn L. Float-over installation method comprehensive comparision between numerical and model test results. J Offshore Mech Arctic Eng, 2006, 128(3): 257-262

[15] Wang B, Yang XL, Zhang GL, . Key technologies of DP float-over installation and corresponding feasibility analysis in the East China Sea. Shipbuilding of China, 2017, 58: 162-169

[16] Xia J, Hayne S, Macfarlane G, . Investigation into float-over installations of minimal platforms by hydrodynamic model testing. ASME Int Conf Offshore Mech Arctic Eng, 2005, 62(3): 193-215

[17] Xu X, Yang J M, Li X, et al (2013) Wave drift forces on three barges arranged side by side in float-over installation. Proc. 32th Int. Conf. on Offshore Mechanics and Arctic Engineering (ASME), Nantes, France. DOI: https://doi.org/10.1115/OMAE2013-10737

[18] Xu X, Yang JM, Li X, Xu LY. Hydrodynamic performance study of two side-by-side barges. Ship Offshore Structure, 2014, 9(5): 475-488

[19] Xu X, Yang JM, Li X, Xu LY. Time-domain simulation for coupled motions of three barges moored side-by-side in float-over operation. China Ocean Eng, 2015, 29: 155-168