Blar i Institutt for marin teknikk på tittel
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A Numerical and Theoretical Study of a Multi-torus Solar Island Concept
(Master thesis, 2020)Teoretiske og numeriske studier er gjennomført for en flytende konstruksjon bestående av sirkulære flytere koblet sammen med elastiske bånd, en såkalt multiflyter. Stukturen er designet for å være et flytende fundament for ... -
A Numerical Study of a Damaged Ship in Beam Sea Waves
(Doktoravhandlinger ved NTNU, 1503-8181; 2009:268, Doctoral thesis, 2009)An important objective of survivability criteria for passenger vessels is to ensure that there is sufficient time called Time To Capsizing (TTC) to evacuate passengers and crew members in case of emergency. This requires ... -
A Numerical Study of a Multi-torus Floating Solar Island Concept, with the use of Computer Programming
(Master thesis, 2020)En halvt nedsenket fler-torus modell er implementert numerisk, med hensikt å undersøke responsen til en slik struktur. Den numeriske modellen, bestående av flere sirkulære flytere koblet sammen med elastiske bånd (strekkstag), ... -
A numerical study of the second-order wave excitation of ship springing by a higher-order boundary element method
(Journal article; Peer reviewed, 2014)This paper presents some of the efforts by the authors towards numerical prediction of springing of ships. A time-domain Higher Order Boundary Element Method (HOBEM) based on cubic shape function is first presented to solve ... -
A Numerical Study of Wave-in-Deck Impact using a Two-dimensional Constrained Interpolation Profile Method
(Doktoravhandlinger ved NTNU, 1503-8181; 2009:153, Doctoral thesis, 2009)A Constrained Interpolation Profile method following Hu and Kashiwagi (2004) is developed for wave impact applications. Two-dimensional, unsteady, viscous and incompressible flow is assumed. The numerical model is a finite ... -
A Numerical Study on a Flopper Stopper for Leg Positioning of a Jack-Up Barge
(Chapter; Peer reviewed, 2017)Jack-up barges are commonly used for marine operations in the offshore oil and gas, and offshore wind industries. A critical phase within the marine operation activities is the positioning of the jack-up legs onto the ... -
A Numerical Study on Stratified Shear Layers With Relevance to Oil-Boom Failure
(Chapter, 2014)Interface dynamics of two-phase flow, with relevance for leakage of oil retained by mechanical oil barriers, is studied by means of a 2D lattice-Boltzmann method combined with a phase-field model for interface capturing. ... -
A numerical study on vortex-induced vibrations and the effect of slurry density variations on fatigue of ocean mining risers
(Journal article; Peer reviewed, 2019)Ocean mining emerges as a way of meeting future demands for valuable minerals. Risers conveying ore from the seabed to the surface must withstand large wave and current loads. In addition, vortex-induced vibrations (VIV) ... -
A parametric study on the final blade installation process for monopile wind turbines under rough environmental conditions
(Journal article; Peer reviewed, 2018)Single blade installation is a method for installing wind turbine blades. If a jack-up vessel is used during an o shore installation, the wind turbine blade is mainly subjected to wind loads and experiences resonant motions, ... -
A particle filter SLAM approach to online iceberg drift estimation from an AUV
(Chapter; Peer reviewed, 2017)Using autonomous underwater vehicles (AUVs) for mapping the underwater topography of sea-ice and icebergs, or detecting keels of ice ridges, is foreseen as an enabling technology in future Arctic offshore operations. This ... -
A phenomenological explanation of the pressure-area relationship for the indentation of ice: Two size effects in spherical indentation experiments
(Journal article, 2015)Indentation tests provide a simple means to study the inelastic behavior of ice and other materials when loaded under a compressive stress state. Such tests provide force–time plots which are often converted to pressure–area ... -
A Preliminary Analysis of the Crushing Specific Energy of Iceberg Ice under Rapid Compressive Loading
(Journal article, 2017)Indentation tests are used to study inelastic response of ice and other materials when loaded under a compressive stress state. Indentation testing provides force–time plots which are often converted to pressure–area curves, ... -
A probabilistic approach for the quantification of prediction error in deterministic phase-resolved wave forecasting
(Journal article; Peer reviewed, 2018)This paper presents a semi-analytical methodology for the determination of prediction error statistics in deterministic sea wave predictions (DSWP), based on linear wave models. The underlying wave elevation is modelled ... -
A prognostic method for fault detection in wind turbine drivetrains
(Journal article; Peer reviewed, 2014)In this paper, a prognostic method is presented for fault detection in gears and bearings in wind turbine drivetrains. This method is based on angular velocity measurements from the gearbox input shaft and the output to ... -
A rational approach to seepage flow effects on bottom friction beneath random waves
(Journal article, 2014)The bottom friction beneath random waves is predicted taking into account the effect of seepage flow. This is achieved by using wave friction factors for rough turbulent, smooth turbulent and laminar flow valid for regular ... -
A Real Option Approach to Value Flexibility in Ship Design
(Master thesis, 2020)This thesis evaluates whether implementation of flexibility in ship design is a suitable approach to handle an uncertain future. Flexibility exploits opportunities and reduces downside risk. However, a flexible design is ... -
A real-time simulator framework for marine power plants with weak power grids
(Journal article, 2017)This work takes aim at presenting a generic real-time simulation framework for marine power plants with weak power grids, containing transient functionalities such as starting and stopping of arbitrary generators, and phase ... -
A reliability study of a Deepwater Vertical Xmas Tree with attention to XT retrieval rate
(Master thesis, 2014)The focus of this thesis is towards the subsea Xmas Tree (XT) system. The XT is recognized by the industry as an overall reliable configuration, but as in all development projects, it is a constant battle to optimize the ... -
A review of slamming load application to offshore wind turbines from an integrated perspective
(Journal article; Peer reviewed, 2017)In harsh sea conditions, it is possible for offshore wind turbines (OWTs) to be exposed to slamming loads due to breaking waves, especially plunging breaking waves. These slamming loads lead to significant structural ... -
A review of structural responses and design of offshore tubular structures subjected to ship impacts
(Journal article, 2018)Over the past decades, the offshore oil and gas industry has developed rapidly. A large number of offshore structures, notably jacket and jack-up platforms, were constructed and installed worldwide. As they are often exposed ...