• A 2D Experimental and Numerical Study of Moonpools With Recess 

      Ravinthrakumar, Senthuran; Kristiansen, Trygve; Ommani, Babak (ASME 2018 37th International Conference on Ocean, Offshore and Arctic Engineering;OMAE2018-78326, Chapter, 2018-06-25)
      Moonpool resonance is investigated in a two-dimensional setting in terms of regular, forced heave motions of a model with moonpool with different rectangular-shaped recess configurations. A recess is a reduced draft zone ...
    • Bilge keel induced roll damping of an FPSO with sponsons 

      Ommani, Babak; Fonseca, Nuno; Kristiansen, Trygve; Bakksjø, Hanne (ASME 2016 35th International Conference on Ocean, Offshore and Arctic Engineering - Volume 1: Offshore Technology;Offshore Geotechnics;OMAE2016-54420, Chapter, 2016-06)
      The bilge keel induced roll damping of an FPSO with sponsons is investigated numerically and experimentally. The influence of the bilge keel size, on the roll damping is studied. Free decay tests of a three-dimensional ...
    • Coupled vessel and moonpool responses in regular and irregular waves 

      Ravinthrakumar, Senthuran; Kristiansen, Trygve; Molin, Bernard Jean Marie; Ommani, Babak (Journal article; Peer reviewed, 2020-03)
      Hydrodynamic coupling between the ship and moonpool responses is investigated. Dedicated experiments are carried out in the Ocean Basin at Sintef Ocean. Three different moonpool sizes are studied, where the moonpool length ...
    • Investigating a Simplified Model for Moonpool Piston Mode Response in Irregular Waves 

      Ommani, Babak; Kristiansen, Trygve; Berget, Kjetil (ASME digital collection;OMAE2018-78352, Chapter, 2018-06-25)
      Estimating moonpool piston mode response at resonance is important for operation safety. This is a difficult task, in particular, due to nonlinear nature of the moonpool response connected to the damping imposed by the ...
    • OC2018 A-116 - Loads, design and operation of floaters in the Arctic - Ptil – NORD ST20 

      Ommani, Babak; Berthelsen, Petter Andreas; Firoozkoohi, Reza (SINTEF Ocean rapporter;OC2018 A-116, Research report, 2018-12-11)
      This report presents results from hydrodynamic analysis of interaction between glacial ice and semisubmersible drilling units, as part of the Petroleum Safety Authority's project "NORD ST20 Loads, design and operation of ...
    • On Common Research Needs for the Next Generation of Floating Support Structures 

      Aksnes, Vegard Øgård; Alsos, Hagbart Skage; Bachynski-Polic, Erin Elizabeth; Berthelsen, Petter Andreas; Delhaye, Virgile Roger; Furevik, Birgitte Rugaard; Jostad, Hans Petter; Kristiansen, Trygve; Ommani, Babak (Chapter; Peer reviewed, 2022)
      The world is facing several industrial and societal challenges, such as providing enough renewable energy and enough safe and healthy food as formulated in the United Nations sustainable development goals. Using floating ...
    • Operability analysis of control system for ROV launch-and-recovery from autonomous surface vessel 

      Tran, Celine; Gushkov, Ivan Ivanov; Nordvik, Kristoffer; Røang, Simen Troye; Lysthaug, Simen Brodalen; Ommani, Babak; Fossen, Thor I.; Hassani, Vahid; Smines, Vidar; Johansen, Tor Arne (Journal article; Peer reviewed, 2023)
      The launch and recovery of equipment such as remotely operated vehicles (ROVs) is a critical task that defines the operability limits of many marine operations. This paper considers the analysis of control systems that are ...
    • A Physical-Based Damping Model of Gap and Moonpool Resonance in WAMIT 

      Ravinthrakumar, Senthuran; Ommani, Babak; Kristiansen, Trygve; Olimb, Idunn; Lyngvær, Bernt Karsten (Chapter; Peer reviewed, 2022)
      An engineering model to estimate and incorporate quadratic damping of the piston-mode moonpool responses in the proximity of the piston mode period is proposed. The model provides a physical-based equivalent linearized ...
    • Simulation of Low Frequency Motions in Severe Seastates Accounting for Wave-Current Interaction Effects 

      Ommani, Babak; Fonseca, Nuno; Stansberg, Carl Trygve (ASME Proceedings | Offshore Technology;OMAE2017-62550, Chapter, 2017-06-25)
      Today’s industry practice assumes wave drift forces on floating structures can be computed from zero current wave drift force coefficients for the stationary floater, while simplified correction models introduce current ...
    • Sloshing-induced motions of a spar inside a cylindrical dock with baffles in waves 

      Moreau, Mael Korentin Ivan; Kristiansen, Trygve; Ommani, Babak; Molin, Bernard Jean-Marie (Peer reviewed; Journal article, 2023)
      The motions of a free floating offshore wind turbine’s (OWT) spar-type platform inside a bottom-less moored cylindrical dock are investigated for incident wave frequencies near the first lateral sloshing resonance, focusing ...
    • An upright bottomless vertical cylinder with baffles floating in waves 

      Moreau, Mael Korentin Ivan; Kristiansen, Trygve; Ommani, Babak; Molin, Bernard Jean Marie (Peer reviewed; Journal article, 2022)
      Damping of the surge and pitch motions, as well as the first lateral sloshing mode in a rigid free-floating upright circular dock with bilge boxes and open bottom is investigated. Model tests are carried out on a 0.80 m ...
    • Waves' numerical dispersion and damping due to discrete dispersion relation 

      Ommani, Babak; Faltinsen, Odd Magnus (ASME Digital colletion;OMAE2014-23152,, Chapter, 2014-06)
      In linear Rankine panel method, the discrete linear dispersion relation is solved on a discrete free-surface to capture the free-surface waves generated due to wave-body interactions. Discretization introduces numerical ...