|Table of Contents|

Citation:
　Shivaji Ganesan T.,Debabrata Sen.Air Gap Prediction for Floating Bodies Using a 3D Numerical Wave Tank Approach[J].Journal of Marine Science and Application,2018,(4):531-549.[doi:10.1007/s11804-018-00059-1]
Click and Copy

Air Gap Prediction for Floating Bodies Using a 3D Numerical Wave Tank Approach

Info

Title:
Air Gap Prediction for Floating Bodies Using a 3D Numerical Wave Tank Approach
Author(s):
Shivaji Ganesan T.1;  Debabrata Sen2
Affilations:
Author(s):
Shivaji Ganesan T.1;  Debabrata Sen2
1 Indian Register of shipping, 52-A, Adi shankaracharya Marg, Opp Powai Lake, Powai, Mumbai 400072, India;
2 Department of Ocean Engineering and Naval Architecture, IIT, Kharagpur 721302, India
Keywords:
3D numerical wave tank; Air gap responses; Time-domain approach; Numerical wave; F-K nonlinear
分类号:
-
DOI:
10.1007/s11804-018-00059-1
Abstract:
Computations for air gap response of a semisubmersible platform based on a 3D numerical wave tank approach are presented. The developed method is in time domain and can consider nonlinearities associated with incident wave and hydrostatic forces exactly in determining the body response, but the interaction hydrodynamics of radiation and diffraction are based on simplified linearization assumptions. The incident wave can be defined by any suitable wave theory and here defined by a fully nonlinear numerical wave model. After verifying the present computations results in its degenerated linearized version against the usual linear 3D Green function-based frequency-domain results for air gap predictions, systematic comparative studies are undertaken between linear and the approximate nonlinear solutions. It is found that nonlinear computations can yield considerably conservative predictions as compared to fully linear calculations, amounting to a difference of up to 30%-40% in the minimum air gap in steep ambient incident waves at high and moderate frequencies.

References:

Chen X, Wu B (2014) Air gap calculation and the effect of wave diffraction and higher order waves. Proceedings of the 11th International Conference on Hydrodynamics (ICHD-2014), Singapore
Dong Z, Zhan J (2009) Numerical modelling of wave evolution and runup in shallow water. J Hydrodyn 21(6):731-738. https://doi.org/10.1016/S1001-6058(08)60207-3
Ganesan TS, Sen D (2015a) Time-domain simulation of large-amplitude wave-structure interactions by a 3D numerical tank approach. J Ocean Eng Mar Energy 1:299-324. https://doi.org/10.1007/s40722-015-0024-4
Ganesan TS, Sen D (2015b) Direct time domain analysis of floating structures with linear and nonlinear mooring stiffness in a 3D numerical wave tank. Appl Ocean Res 51:153-170. https://doi.org/10.1016/J.APOR.2015.04.002
Iwanowski B, Lefranc M, Wemmenhove R (2009) CFD simulation of wave run-up on a semi-submersible and comparison with experiment. In ASME Proceedings of OMAE-2009, pp 19-29. https://doi.org/10.1115/OMAE2009-79052
Jørgen K, Oosterlaak V, Kvillum T (2014) Non-linear air gap analyses of a semi-submersible compared with linear analyses and model tests. In ASME proceedings of OMAE-2014. https://doi.org/10.1115/OMAE2014-24044
Kazemi S, Incecik A (2005) Numerical prediction of air-gap response of floating offshore structures using direct boundary element method. In ASME proceedings of OMAE-2005. Halkidiki, Greece, Paper no-OMAE2005-67399. https://doi.org/10.1115/OMAE2005-67399
Kim MW, Koo W, Hong SY (2014) Numerical analysis of various artificial damping schemes in a three-dimensional numerical wave tank. Ocean Eng 75:165-173. https://doi.org/10.1016/J.OCEANENG.2013.10.012
Kurniawan A, Huang Z, Jing L, Liu C, Wang X, Hao Z, Tan SK, Edwin N (2009) A numerical analysis of the response and air gap demand for semi-submersibles. ASME Proceedings of OMAE-2009. Honolulu, Hawaii,USA. Paper no.-OMAE2009-79163. https://doi.org/10.1115/OMAE2009-79163
Manuel L, Winterstein SR (2000) Reliability based predictions of a design air gap for floating offshore structures. In Proceedings 8th ASCE Conf. on Probabilistic Mechanics and Structural Reliability
Manuel L, Sweetman B, Winterstein SR (2001) Analytical predictions of the air gap response of floating structures. J Offshore Mech Arct Eng 123:112-117. https://doi.org/10.1115/1.1372195
Matsumto FT, Watai RA, Simos AN (2010) Wave run-up and air gap prediction for a large volume semisubmersible platform. In ASME proceedings of OMAE-2010. Shanghai, China. Paper noOMAE2010-20165. https://doi.org/10.1115/1.4007380
Naess A, Gaidai O (2011) Extreme value statistics of non-Gaussian random wave fields and the air gap problem for offshore platforms. In Proceedings of the 8th International Conference on Structural Dynamics, EURODYN 2011Leuven, Belgium, 4-6 July 2011.ISBN 978-90-760-1931-4
Nielsen FG (2003) Comparative study on air gap under floating platforms and run-up along platform columns. Mar Struct 16(2):97-134.https://doi.org/10.1016/S0951-8339(02)00023-0
Pinkster JA (1980) Low frequency Second order wave exciting forces on floating structures. Ph.D. Thesis, Delft University of Technology
Rienecker MM, Fenton JD (1981) A Fourier approximation method for steady water waves. J Fluid Mech 104:119-137. https://doi.org/10.1017/S0022112081002851
Shan TB, Yang JM, Li X, Xiao LF (2011) Experimental investigation on wave run-up characteristics along columns and air gap response of semisubmersible platform. J Hydrodyn 23(5):625-636. https://doi.org/10.1016/S1001-6058(10)60158-8
Simos AN, Sparano JV, Aranha JAP, Matos VLF (2008) 2nd order hydrodynamic effects on resonant heave, pitch and roll motions of a large-volume semisubmersible platform. In ASME proceedings of OMAE-2008. Estoril, Portugal, Paper no-OMAE2008-57430. https://doi.org/10.1115/OMAE2008-57430
Sweetman B (2004) Practical air gap prediction of offshore structures. J Offshore Mech Arct Eng 126:147-155. https://doi.org/10.1115/1.1710870
Sweetman B, Winterstein SR (2003) Non-Gaussian air gap response models for floating structures. J Eng Mech 129(3):302-309. https://doi.org/10.1061/(ASCE)0733-9399(2003)129:3(302)
Sweetman B, Winterstein SR, Meling TS, Birknes J (2001) Air gap prediction:use of second-order diffraction and multicolumn models. In Proceedings of ISOPE 2001-IL-13, ISOPE-2001, available from http://www.rms-group.org
Sweetman B, Winterstein SR, Cornell CA (2002) Air gap analysis of floating structures:first-and second-order transfer functions from system identification. Appl Ocean Res 24(2):107-118. https://doi.org/10.1016/S0141-1187(02)00010-X
Winterstein SR, Sweetman B (2001) Air gap response of floating structures:statistical predictions vs observed behavior. J Offshore Mech Arct Eng 123:118-123. https://doi.org/10.1115/1.1377867
Yan F, Yang H, Shen P, Zhang D, Sun L (2014) A probability distribution of air-gap and wave run-up by model tests of a horizontal moored semi-submersible platform. ASME Proceedings of OMAE-2014. https://doi.org/10.1115/OMAE2014-23021

Memo

Memo:
Received date:2017-7-7;Accepted date:2017-11-19。
Corresponding author:Shivaji Ganesan T.,shivaji@irclass.org,shiva.naro@gmail.com
Last Update: 2019-03-05