A face-contact connector for modularized floating structures

Vortex-Induced Motions (VIM) of floating structures is a very relevant subject for the design of mooring and riser systems. In the design phase, Spar VIM behavior as well as Semi Submersible and Tension Leg Platform (TLP) flow-induced motions are studied and evaluated. This paper discusses flow-induced behavior on the Monocolumn concept by presenting a phenomenological model and comparing its results with a set of experiments that took place in the IPT Towing Tank - Brazil (September 2008). The experimental results have shown some fundamental differences from previous VIM tests on other units such as Spars. This numerical model attempts to identify these disparities in order to better understand the mechanics of this phenomenon. The model is based on a time-domain, two degree-of-freedom structural model coupled with a van der Pol type wake oscillator. The comparison was performed in order to calibrate the model, to study and better understand the tests results, and finally to identify important aspects to investigate in further experiments.

Download Full-text

Lessons Learned to Improve the Resiliency of Floating Structures

Ports 2016 ◽

10.1061/9780784479919.042 ◽

2016 ◽

Author(s):

Matthew L. Teeden

Keyword(s):

Lessons Learned ◽

Floating Structures

Download Full-text

ACCELERATED BEM FOR WAVE RESPONSE ANALYSIS OF VERY LARGE FLOATING STRUCTURES

Structural Stability and Dynamics ◽

10.1142/9789812776228_0079 ◽

2002 ◽

Cited By ~ 1

Author(s):

T. Utsunomiya ◽

E. Watanabe

Keyword(s):

Response Analysis ◽

Floating Structures ◽

Wave Response ◽

Very Large Floating Structures

Download Full-text

A Numerically Efficient Method for Analysis of Very Large Articulated Floating Structures

Journal of Ship Research ◽

10.5957/jsr.1998.42.3.174 ◽

1998 ◽

Vol 42 (03) ◽

pp. 174-186

Author(s):

C. J. Garrison

Keyword(s):

Hydrodynamic Interaction ◽

Near Field ◽

Three Dimensional ◽

Computational Effort ◽

Floating Structure ◽

Complete Structure ◽

Field Interaction ◽

Floating Structures ◽

Computing Effort ◽

The Individual

A method is presented for evaluation of the motion of long structures composed of interconnected barges, or modules, of arbitrary shape. Such structures are being proposed in the construction of offshore airports or other large offshore floating structures. It is known that the evaluation of the motion of jointed or otherwise interconnected modules which make up a long floating structure may be evaluated by three dimensional radiation/diffraction analysis. However, the computing effort increases rapidly as the complexity of the geometric shape of the individual modules and the total number of modules increases. This paper describes an approximate method which drastically reduces the computational effort without major effects on accuracy. The method relies on accounting for hydrodynamic interaction effects between only adjacent modules within the structure rather than between all of the modules since the near-field interaction is by far the more important. This approximation reduces the computational effort to that of solving the two-module problem regardless of the total number of modules in the complete structure.

Download Full-text

Numerical Research on FPSOs With Green Water Occurrence

Journal of Ship Research ◽

10.5957/jsr.2009.53.1.7 ◽

2009 ◽

Vol 53 (01) ◽

pp. 7-18

Author(s):

Renchuan Zhu ◽

Guoping Miao ◽

Zhaowei Lin

Keyword(s):

Three Dimensional ◽

Green Water ◽

Floating Body ◽

Incoming Wave ◽

Model Case ◽

Floating Structures ◽

Design And Optimization ◽

Head Waves ◽

Wave Heights ◽

The Impact

Green water loads on sailing ships or floating structures occur when an incoming wave significantly exceeds freeboard and water runs onto the deck. In this paper, numerical programs developed based on the platform of the commercial software Fluent were used to numerically model green water occurrence on floating structures exposed to waves. The phenomena of the fixed floating production, storage, and offloading unit (FPSO) model and oscillating vessels in head waves have been simulated and analyzed. For the oscillating floating body case, a combination idea is presented in which the motions of the FPSO are calculated by the potential theory in advance and computional fluid dynamics (CFD) tools are used to investigate the details of green water. A technique of dynamic mesh is introduced in a numerical wave tank to simulate the green water occurrence on the oscillating vessels in waves. Numerical results agree well with the corresponding experimental results regarding the wave heights on deck and green water impact loads; the two-dimensional fixed FPSO model case conducted by Greco (2001), and the three-dimensional oscillating vessel cases by Buchner (2002), respectively. The research presented here indicates that the present numerical scheme and method can be used to actually simulate the phenomenon of green water on deck, and to predict and analyze the impact forces on floating structures due to green water. This can be of great significance in further guiding ship design and optimization, especially in the strength design of ship bows.

Download Full-text

Launching of Ships and Floating Structures from Horizontal Berth by Tipping Table

Journal of Ship Production ◽

10.5957/jsp.1998.14.4.265 ◽

1998 ◽

Vol 14 (04) ◽

pp. 265-276

Author(s):

Ivo Senjanovic

Keyword(s):

Structural Dynamics ◽

Review Paper ◽

Offshore Structures ◽

Model Tests ◽

Full Scale ◽

Strength Analysis ◽

Test Results ◽

Floating Structures ◽

Measurement Results

This review paper covers extensive investigations which were undertaken in order to verify the idea of launching of ships and other floating structures from a horizontal berth by a set of turning pads. This includes structural dynamics during launching, model tests and strength analysis of the structure and the launching system. The most important results, which were used for the design of the launching system, are presented. The preparation of a barge for side launching is described, and the full-scale measurement results are compared with the test results. The advantages of building ships and offshore structures on a horizontal berth are pointed out in the conclusion.

Download Full-text