Development of Ice Load Generation Module to Evaluate Station-Keeping Performance for Arctic Floating Structures in Time Domain

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.

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Computer Simulations of the Behavior of Maritime Structures

Marine Technology and SNAME News ◽

10.5957/mt1.1986.23.2.139 ◽

1986 ◽

Vol 23 (02) ◽

pp. 139-157

Author(s):

J. P. Hooft

Keyword(s):

Computer Simulations ◽

Time Domain ◽

Ocean Engineering ◽

Floating Structures ◽

Marine Technology ◽

Calculation Models

This paper discusses the setup of calculation models for the effectuation of time domain computer simulations of the behavior of floating structures. Special attention is devoted to the development of simple and reliable mathematical descriptions of the effects of external phenomena which may influence the behavior of the structure. The paper also indicates the applicability of time domain simulations for various areas of marine technology and ocean engineering, and refers to various publications in which time domain computer simulations and the results thereof have been presented.

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Station Keeping Trials in Ice: Ice Load Monitoring System

Volume 8: Polar and Arctic Sciences and Technology; Petroleum Technology ◽

10.1115/omae2018-78709 ◽

2018 ◽

Author(s):

Håvard Nyseth ◽

Anders Hansson ◽

Johan Johansson Iseskär

Keyword(s):

Data Sets ◽

Station Keeping ◽

Ice Load ◽

Hull Structure ◽

Load Monitoring ◽

Ice Loads ◽

Recorded Data ◽

Measurement Concept ◽

Ice Impacts ◽

Basic Philosophy

In connection with the Statoil SKT project, DNV GL have developed a method for estimating ice loads on the ship hull structure and mooring tension of the anchor handling tug supply (AHTS) vessel Magne Viking by full scale measurements. In March 2017, the vessel was equipped with an extensive measurement system as a preparation for the dedicated station-keeping trial in drifting ice in the Bay of Bothnia. Data of the ice impacts acting on the hull were collected over the days of testing together with several other parameters from the ship propulsion system. Whilst moored, the tension in the mooring chain was monitored via a load cell and logged simultaneously to the other parameters. This paper presents the processes involved in developing the measurement concept, including the actual installation and execution phases. The basic philosophy behind the system is described, including the methods used to design an effective measurement arrangement, and develop procedures for estimation of ice loads based on strain measurements. The actual installation and the process of obtaining the recorded data sets are also discussed.

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Advances in the Development of a Time-Domain Unstructured Finite Element Method for the Analysis of Waves and Floating Structures Interaction

Computational Methods in Applied Sciences - MARINE 2011, IV International Conference on Computational Methods in Marine Engineering ◽

10.1007/978-94-007-6143-8_7 ◽

2013 ◽

pp. 127-136

Author(s):

Borja Servan-Camas ◽

Julio Garcia-Espinosa

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Time Domain ◽

Floating Structures ◽

Element Method

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Time-domain simulation for water wave radiation by floating structures (Part A)

Journal of Marine Science and Application ◽

10.1007/s11804-008-8033-5 ◽

2008 ◽

Vol 7 (4) ◽

pp. 226-235 ◽

Cited By ~ 7

Author(s):

Gang Xu ◽

Wen-yang Duan

Keyword(s):

Time Domain ◽

Water Wave ◽

Wave Radiation ◽

Time Domain Simulation ◽

Floating Structures

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A Direct Time Domain Simulation of Floating Structures With Mooring Lines

Volume 3: Materials Technology; Jan Vugts Symposium on Design Methodology of Offshore Structures; Jo Pinkster Symposium on Second Order Wave Drift Forces on Floating Structures; Johan Wichers Symposium on Mooring of Floating Structures in Waves ◽

10.1115/omae2011-49283 ◽

2011 ◽

Cited By ~ 1

Author(s):

Jingpu Chen ◽

Dexiang Zhu

Keyword(s):

Time Domain ◽

Time Domain Method ◽

Test Results ◽

Time Domain Simulation ◽

Mooring Lines ◽

Restoring Force ◽

Floating Structures ◽

Rankine Panel Method ◽

Domain Method ◽

Force Characteristics

A direct time domain method is established for analyzing the interactions between the floating structures and mooring lines. The motions of floating structures are solved by a Rankine Panel method in time domain, while the static restoring force characteristics of the mooring system is taken into account. As numerical examples, the motions of two SPARs are solved by this direct time domain method. The numerical results of present method are analyzed and compared with model test results.

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