Blar i NTNU Open på forfatter "Leira, Bernt Johan"
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Evaluation of Extreme Design Wave Loads for Hull Girder Strength Assessment
Ravinthrakumar, Senthuran (Master thesis, 2016)Ships may operate in severe sea states, which might induce large vertical bending moments. The classification rules have developed empirical curves for the extreme wave-induced vertical bending moments. It is therefore of ... -
Experimental study of drilling riser and wellhead force by small scale testing
Wang, Huanhuan; Yang, Jin; Zhang, Dongyufu; Sævik, Svein; Leira, Bernt Johan; Xu, Fei; Li, Xiao (Peer reviewed; Journal article, 2022)Small-scale model tests of a drilling riser were conducted, aiming at a better understanding of the mechanical transfer of forces from the drilling riser to the wellhead. The tests were conducted in a water tank with ... -
Extreme Value Analysis of Riser Systems for large Water Depths
Bollestad, Geir Inge (Master thesis, 2014)In relevant Norwegian regulations, the characteristic response is defined as a given annual probability of exceedance. Effective and accurate methods of estimating the response for the required annual probability levels ... -
Extreme Value Estimation of Beaufort Sea Ice Dynamics Driven by Global Wind Effects
Sinsabvarodom, Chana; Næss, Arvid; Leira, Bernt Johan; Chai, Wei (Journal article; Peer reviewed, 2022) -
Extreme Value Estimation of Mooring Loads Based on Station-Keeping Trials in Ice
Sinsabvarodom, Chana; Leira, Bernt Johan; Chai, Wei; Næss, Arvid (OMAE2020-18172, Chapter; Peer reviewed, 2020)he purpose of this work is to perform an extreme value estimation of the mooring loads associated with station-keeping of a ship operating in ice. In general, the design of mooring lines is based on estimation of the extreme ... -
Fabrication of the Hywind Substructure
Bjerkelund, Kristoffer (Master thesis, 2016)As the technological feasibility of the Hywind has been proven through the Hywind demo project, the way forward is to check the technological and economic feasibility of upscaling the fabrication. In the last years, several ... -
Fabrication, Launching and Towing of Submerged Production Unit - A Technology Development Project of Subsea7
Arumugam Elumalai, Venkatesan (Master thesis, 2018)The demand for fossil fuels drives for an advancement in the existing subsea technology. The developments evolved as the search for hydrocarbons moved from onshore to offshore, followed by a transition from shallow to deep ... -
Fatigue Assessment of Mooring Chain Considering the Effects Of Mean Load and Corrosion
Lone, Erling Neerland; Sauder, Thomas Michel; Larsen, Kjell; Leira, Bernt Johan (Peer reviewed; Journal article, 2021)Results from full scale fatigue tests of offshore mooring chains performed in recent years have revealed considerable influence of both mean load and corrosion condition on the fatigue capacity. It has been shown that a ... -
Fatigue Design Appropriations for Floating Offshore Wind Turbine Support Structures
Stokker, Sophie Holme (Master thesis, 2023)Flytende havvindturbiner (FOWT) utvikles for å utvide vindkraftproduksjonen til områder langt fra kysten og i dypere farvann. Ved å bruke erfaringen fra olje- og gassindustrien innen offshorestrukturer, kan FOWT-design dra ... -
Fatigue in Jacket Structures With Impaired Integrity
Flesche, Arve (Master thesis, 2012)Present regulations for offshore structures on the Norwegian continental shelf havea requirement for Accidental Limit State redundancy and Fatigue Limit State redundancyin a damaged state. However, the requirement is far ... -
Fatigue life estimates based on unit load approach
Manne, Phani Kumar (Master thesis, 2015) -
Fatigue Lifetime Assessment of Typical Longitudinal/End Connections for Large Offshore Service Construction Vessels (OSCVs). - Application of Finite Element Method Software and Rule Loads
Steffensen, Mads Vambheim (Master thesis, 2015)In the last decades there has a major development of the Offshore Service Construction Vessels (OSCV) where high tensile steel has been introduced to increase the dead weight, but also to increase the allowable stress ... -
Fatigue reliability assessment of offshore wind turbines with stochastic availability
Horn, Jan-Tore H.; Leira, Bernt Johan (Journal article; Peer reviewed, 2019)In this paper, the impact on lifetime estimation of an offshore wind turbine by introducing a stochastic model for the availability is investigated. Offshore bottom-fixed wind turbines typically have an average downtime ... -
Fatigue reliability of mooring chains, including mean load and corrosion effects
Lone, Erling Neerland; Sauder, Thomas Michel; Larsen, Kjell; Leira, Bernt Johan (Peer reviewed; Journal article, 2022)A reliability formulation for mooring chain fatigue is developed, including the effects of mean load and degradation due to corrosion. They are included by starting from a S-N model with parameterized dependence to the ... -
Floating Production in general, and a Parameter Study of a Flexible Riser for the Goliat FPSO in specific
Reinertsen, Andrea (Master thesis, 2017)A floating production system (FPS) consists of a floating structure, a mooring system, anchors and risers. Such systems enable production for larger ocean depths. Risers are vertical pipes used for transportation of ... -
A Framework for Condition Monitoring and Risk-Based Decision Support Involving a Vessel State Observer
Han, Xu; Leira, Bernt Johan; Sævik, Svein; Radhakrishnan, Gowtham; Skjong, Stian; Kyllingstad, Lars Tandle (Chapter, 2021)Digital twins have attracted significant attention across different domains for decades. In the maritime and the energy industries, digital twins have been mainly used for system condition monitoring, project visualization, ... -
From Teaching as Transmission to Constructive Alignment: A Case Study of Learning Design
Gynnild, Vidar; Leira, Bernt Johan; Holmedal, Lars Erik; Myrhaug, Dag; Coll Mossige, Jon (Peer reviewed; Journal article, 2021)This paper reports on an action research study on curriculum design in an optional module at the Norwegian University of Science and Technology. There were two professors teaching their respective parts, henceforth termed ... -
Full long-term extreme response analysis of marine structures using inverse FORM
Giske, Finn-Idar Grøtta; Leira, Bernt Johan; Øiseth, Ole (Journal article; Peer reviewed, 2017)An exact and an approximate formulation for the long-term extreme response of marine structures are discussed and compared. It is well known that the approximate formulation can be evaluated in a simplified way by using ... -
Global Analysis of a Shipping Lane for a Floating Bridge
Johnsen, Jørn Magnus (Master thesis, 2015)The main objective of this thesis is to conduct a global analysis of a proposed shipping lane for a floating bridge that in future will operate in Halsafjorden. The model is simplified as only the shipping lane will be ... -
Hydroelastic Analysis of Flexible Wedges
Aagaard, Olav (Master thesis, 2013)This thesis presents a simulation method for analyzing the coupled water entry problem of elastic bodies. The water entry problem is investigated using the software STAR CCM+ for computational fluid dynamics and Abaqus for ...