Blar i Institutt for marin teknikk på tittel
Viser treff 3163-3182 av 3421
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Time scale for scour beneath pipelines due to long-crested and short-crested nonlinear random waves plus current
(Journal article; Peer reviewed, 2021)This article derives the time scale of pipeline scour caused by 2D (long-crested) and 3D (short-crested) nonlinear irregular waves and current for wave-dominant flow. The motivation is to provide a simple engineering tool ... -
Time Scales for Scour Below Pipelines and Around Vertical Piles in Nonlinear Random Waves and Current
(Master thesis, 2015)This report presents a stochastic method for predicting the time scale of scour and backfilling, occurring around vertical piles and marine pipelines on the seabed. The erosion occurs due to waves alone or waves com- bined ... -
Time-domain fatigue response and reliability analysis of offshore wind turbines with emphasis on welded tubular joints and gear components
(Doktoravhandlinger ved NTNU, 1503-8181; 2012:331, Doctoral thesis, 2012)Presently fixed support structures are mainly used in the offshore wind industry, e.g. monopile, tripod, gravity base, et al., where the water depth are usually less than 30 m. Research work is ongoing for deeper water ... -
Time-domain floater stress analysis for a floating wind turbine
(Peer reviewed; Journal article, 2023)There are increasing focuses on developing cost-effective floating wind turbines, for which efficient stress analysis methods are needed for floater structural design. Most of the today's studies focus on global analysis ... -
Time-domain Global Response Analysis of a Novel 5MW Semi-submersible Wind Turbine Considering the Effect of Second-order Wave Loads
(Master thesis, 2015)In recent years wind energy industry has been developing very fast, moving from onshore to offshore and from shallow water to deep water. Offshore wind has a huge potential for long-term sustainable energy supply and deeper ... -
Time-domain Roll Motion Analysis of a Barge for Transportation of an Offshore Jacket Structure
(Master thesis, 2018)This paper presents a literature study on roll motions for barges, and time domain and frequency domain simulations. In addition, results from time and frequency domains have been compered in regular and irregular waves ... -
Time-domain simulation of floating wind power plants in irregular seas
(Master thesis, 2011)As the limited fossil energy sources become empty, new sources for energy need to be exploited. One such renewable energy is wind energy. The wind energy potential is high offshore, and is therefore a beneficial location ... -
Time-Domain Simulation of Floating, Dynamic Marine Structures using USFOS
(Master thesis, 2013)This master thesis deals with calculation of the convolution integrals that constitutethe memory functions in the linear time-domain wave response equation. Basictheory needed to calculate the forces acting on floating ... -
Time-domain simulation of marine structures in irregular seas
(Master thesis, 2015)For dynamically sensitive marine structures or marine structures subjected to large displacements the extreme response is often determined on the basis of short term time domain simulation of extreme sea states using the ... -
Time-domain wave estimation and prediction using wave radar on R/V Gunnerus
(Master thesis, 2022)Marine operasjoner beveger seg stadig på dypere vann og mer utfordrende omgivelser. Å garantere sikkerhet i slike omgivelser er en av de viktigste motivasjonene bak forskning i marin teknologi. Nøyaktige forutsigelser for ... -
Time-frequency analysis of acceleration data from ship-ice interaction events
(Journal article; Peer reviewed, 2018)During operations with ships in ice-infested waters, vibrations of the hull occur due to ship-ice interaction. The acting ice load and the induced vibrations depend on the ice regime and ice breaking mechanism. Especially ... -
Time-Varying Model-Based Observer for Marine Surface Vessels in Dynamic Positioning
(Journal article; Peer reviewed, 2017)This paper deals with the problem of transient events in model-based observers for dynamic positioning of marine surface vessels. Traditionally, model-based observers experience a deterioration of performance during ... -
Tools and Methods for Autonomous Operations on Seabed and Water Column using Underwater Vehicles
(Doctoral theses at NTNU;2016:370, Doctoral thesis, 2016)This thesis concerns several aspects of the automatic system that controls the behavior of Remotely Operated Vehicles (ROVs), and elaborates the data collected during the operations. It presents the algorithms used to ... -
Tools and methods to manage risk in autonomous subsea inspection, maintenance and repair operations
(Doctoral theses at NTNU;2018:71, Doctoral thesis, 2018)Autonomous subsea interventions are anticipated to decrease operational costs, reduce response time and optimally maintain the subsea infrastructure. However, the introduction of autonomy may lead to emerging risk factors ... -
Topics in dynamic positioning: System identification, GNSS and MRU lever arm estimation, and hybrid integral action
(Master thesis, 2014)This thesis consists of three main parts. The first part of the master thesis looks at the identification of thruster dynamics and low speed ship dynamics. The relevant parameters identified are time constants and time ... -
Torsion Buckling of Dynamic Flexible Risers
(Master thesis, 2016)Themain purpose of this work is to contribute to better understanding of the torsion structural stability and kink formation process of flexible risers in catenary configuration. The thesis deals with installation criteria ... -
Torsion instability of Dynamic Cables during Installation
(Master thesis, 2017)The oil and gas industry today is a heavily regulated segment, and current standard hasestablished restrictions which yields a very limited weather window for offshore cable installations. This is due to ... -
Torsion instability of Flexible Pipes at the TDP - Torsjonsinstabilitet av fleksible rør med sjøbunnskontakt
(Master thesis, 2017)Dynamic flexible risers are a common term for cables, umbilicals and flexible pipes,that are freely or semi-freely suspended between two points (offshore). Flexible pipes are mostly used to transport fluids between ... -
Total Equipment Monitoring - Ship equipment operation, performance and cost monitoring for VLGCs and LGCs
(Master thesis, 2013)This thesis has been carried out in cooperation with Solvang ASA, as a part of Energy Management in Practice 2 (EMIP-2). EMIP?s vision is to enable a robust knowledge and innovation platform related to energy efficiency ... -
Total experimental uncertainty in hydrodynamic testing of a semisubmersible wind turbine, considering numerical propagation of systematic uncertainty
(Journal article; Peer reviewed, 2020)Quantifying the uncertainty in experimental results is a critical step in properly validating numerical simulation tools for designing floating wind turbines; without a good understanding of the experimental uncertainties, ...