Blar i Institutt for marin teknikk på utgivelsesdato
Viser treff 441-460 av 3421
-
Analysis of Motions and Anchor Line Forces for Floating Production Units
(Master thesis, 2013)The oil industry is expanding its activities into deeper and deeper waters. This creates new challenges in terms of technology and design of floating production units. Floater, mooring lines and risers comprise a dynamic ... -
Experimental results of Discrete Time Variable Structure Control for Dynamic Positioning of Marine Surface Vessels
(Journal article, 2013)This paper presents a Discrete-Time Variable-Structure Control (DTVSC) for the dynamic positioning system of a marine supply vessel to guarantee robustness with respect to disturbances and parametric variations. The control ... -
Mate choice in straight-nosed pipefish (Nerophis ophidion) may be affected by increasing turbidity in the Baltic Sea
(Master thesis, 2013)Mate choice in straight-nosed pipefish (Nerophis ophidion) may be affected by increasing turbidity in the Baltic Sea -
Higher Order Loads from Steep Waves on Drilling Risers
(Master thesis, 2013)Drilling operations are conducted in increasingly harsher environments as the easily accessible oil fields are growing scarce. Marine drilling risers are exposed to large hydrodynamic forces in the splash zone. Higher order ... -
VIV in Free Spanning Pipelines
(Doktoravhandlinger ved NTNU, 1503-8181; 2013:371, Doctoral thesis, 2013)Two important aspects of vortex induced vibrations (VIV) in free spanning pipelines are so far not satisfactorily understood; the complex interaction between in-line (IL) and cross- ow (CF) response, and the signicance of ... -
Time domain-based gear contact fatigue analysis of a wind turbine drivetrain under dynamic conditions
(Journal article; Peer reviewed, 2013)This paper presents a general approach to predict the contact fatigue life of the gears in the drive-train system of a wind turbine under dynamic conditions. A simplified predictive pitting model that estimates service ... -
Probabilistic Design of Midship Panel based on Model scale compressive Ice Test
(Master thesis, 2013)This thesis is investigating compressive ice loads acting on the mid-ship using a model experiment performed in Aalto ice tank where atactile sensor was mounted on the side. In order to get insight in thevery complex ... -
Onset and Progression of Vortical Structures for a Surface Combatant at Drift Angles 0, 10 and 20 Degrees
(Master thesis, 2013)The onset on progression of vortical structures of the ship model DTMB 5512 (geosym of DTMB5415) has been examined for drift angles -1, 10 and 20 degrees, by means of tomographic particle image velocimetry. The drift angle ... -
Konseptutvikling av en offshore supply base plassert i Barentshavet
(Master thesis, 2013)Den globale etterspørselen etter petroleum er økende, og produksjon av olje-og gassressurser flyttes til stadig nye lokasjoner. Dette har ført til et økt fokus på mulighetene for å utvinne petroleum i nordområdene, også i ... -
Reliability-based Gear Contact Fatigue Analysis for Wind Turbines under Stochastic Dynamic Conditions
(Chapter, 2013)This paper describes a method to perform reliability-based gear contact fatigue analysis for wind turbines considering the long-term stochastic wind conditions. A simplified predictive subsurface pitting model for estimating ... -
Dynamic Response of Flexible Pipes During Installation
(Master thesis, 2013)This paper is referring to performing dynamic analysis for an installation scenario with the bi-linear assumption for the bending moment stiffness, which is the governing component stiffness for the curvature at the touching ... -
Collision Between Platform Deck and Service Vessel Wheelhouse
(Master thesis, 2013)Collisions between ships and oshore structures are rarely occurring events, butpose a constant threat to the safety at sea. Observed trends in recent years hasshow that the size of both oshore structures and servicing ... -
Risk-Based Stability Assessment for Semi-Submersible Platforms: Ballast System Failure
(Master thesis, 2013)Stability and buoyancy loss is a very current problem for semi-submersible platforms. New ballast system designs are developed to improve the safety of personnel and facility, but the effect of these is difficult to measure ... -
Modelling and analysis of the gearbox in a floating spar-type wind turbine
(Doktoravhandlinger ved NTNU, 1503-8181; 2013:128, Doctoral thesis, 2013)This thesis seeks to reveal and investigate important drivetrain dynamics in relation to offshore wind turbines. Emphasis is placed on drivetrains of the spar-type floating wind turbines (FWTs). FWTs are proposed to be ... -
Contour Methods for Estimation of Multi-dimensional Extreme Riser Response
(Master thesis, 2013)The aim of this thesis is to investigate the extreme response of a flexible riser.A full long term analysis is usually carried out to find the response with a givenreturn period in years, which is a useful quantity in ... -
Modelling and geometry optimisation of wave energy converters
(Doktoravhandlinger ved NTNU, 1503-8181; 2013:117, Doctoral thesis, 2013)The ultimate goal of wave energy undertaking is to find a solution that minimises the cost of delivered energy. Not only should a device maximise its energy absorption, but also the costs associated with absorbing and ... -
Simulator and Control System Design for a Free Floating Surface Effect Ship at Zero Vessel Speed
(Journal article; Peer reviewed, 2013)This paper covers vertical motion damping of a free floating Surface Effect Ship (SES) at zero vessel speed. Vertical motion damping is requested at the bow deck of the SES during offshore wind turbine docking operation. ... -
Joint Environmental Data at Five European Offshore Sites for Design of Combined Wind and Wave Energy Devices
(Chapter; Peer reviewed, 2013)The costs for an offshore wind farm, especially with bottom fixed foundations increase significantly with increasing water depth. If costs can be reduced to a competitive level, the potential for wind farms in deep water ... -
Application of CFD to seakeeping
(Master thesis, 2013)Simulations were done in both Star-CCM+ and FINE/Marine in both calm water and in waves on the KVLCC2 hull. Due to problems and following time limitations only one wave were simulated in FINE/Marine, and 7 wave cases were ... -
Flow past porous cylinders and effects of biofouling and fish behavior on the flow in and around Atlantic salmon net cages
(Doktoravhandlinger ved NTNU, 1503-8181; 2013:312, Doctoral thesis, 2013)Norwegian salmon aquaculture has experienced a tremendous growth within the past decades and Norway is today the biggest salmon producer in the world. The growth of aquaculture production was enabled by technological ...