The effect of tether-riser dynamics on the response characteristics of deep water tension leg platforms in water depths 900 m and 1800 m under random waves is investigated using a developed nonlinear finite element analysis program in the time-domain. Updated Lagrangian coordinates and incremental iterative solution based on Newmark’s integration scheme are adopted. Linear wave theory is used. Relative velocity form of Morison’s equation is used for estimating the wave forces. Current forces are also included in the analysis. Results are reported in the form of statistical values of responses. The statistical values of responses are found to increase with water depth and significant increase is observed when risers are included.

Issue Section:
Strutures, Safety and Reliability
Keywords:
iterative methods, ocean waves, offshore installations, random processes, tether-riser dynamics, random waves, tension leg platforms, Morison’s equation, nonlinear finite element analysis
Topics:
Finite element analysis, Pipeline risers, Risers (Casting), Tension-leg platforms, Water, Waves, Dynamics (Mechanics), Morison equation, Dynamic analysis
1.
Bhattacharyya
,
S. K.
,
Sreekumar
,
S.
, and
Idichandy
,
V. G.
, 2003, “
Coupled Dynamics of Seastar Mini Tension Leg Platform
,”
Ocean Eng.
0029-8018,
30
(
6
), pp.
709
–
737
.
Crossref
Search ADS
 
2.
Lyons
,
G. J.
, and
Patel
,
M. H.
, 1984, “
Comparisons of Theory With Model Test Data for Tensioned Buoyant Platforms
,”
ASME J. Energy Resour. Technol.
0195-0738,
106
, pp.
426
–
436
.
Crossref
Search ADS
 
3.
Chakrabarti
,
S. K.
, 1971, “
Discussion on Dynamics of Single Buoy Mooring in Deep Water
,”
J. Waterway, Port, Coastal, Ocean Eng.
0733-950X,
97
, pp.
558
–
590
.
4.
Kim
,
M. H.
,
Tahar
,
A.
, and
Kim
,
Y. B.
, 2001, “
Variability of TLP Motion Analysis Against Various Design Methodologies/Parameters
,”
Proceedings of the 11th International Offshore and Polar Engineering Conference
, pp.
467
–
473
.
5.
Ma
,
W.
,
Lee
,
M. Y.
,
Zou
,
J.
, and
Huang
,
E. W.
, 2000, “
Deepwater Nonlinear Coupled Analysis Tool
,”
Proceedings of the Offshore Technology Conference
, Paper No. OTC12085.
6.
Wichers
,
J.
, and
Devlin
,
P. V.
, 2004, “
Benchmark Model Tests on the Deep Star Theme Structures FPSO, SPAR and TLP
,”
Proceedings of the Offshore Technology Conference
, Paper No. OTC 16582.
7.
Zou
,
J.
,
Ormberg
,
H.
, and
Stansberg
,
C. T.
, 2004, “
Prediction of TLP Responses: Model Tests vs. Analysis
,”
Proceedings of the Offshore Technology Conference
, Paper No. OTC 16584.
8.
API-RP2T
, 1997,
Recommended Practice for Planning, Designing and Constructing Tension Leg Platforms
, 2nd ed.,
American Petroleum Institute
,
Washington, DC
.
Copyright © 2010
 by American Society of Mechanical Engineers
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