Browsing Institutt for marin teknikk by Title
Now showing items 3405-3424 of 3471
-
Voluntary Speed Loss of Ships
(Master thesis, 2017)When a ship is caught in heavy seas, speed loss follows. This thesis focuses on the subjective part of speed loss; voluntary speed reductions to maintain the safety of the ship, the cargo and the people. The objective is ... -
Vortex dislocation mechanisms in the near wake of a step cylinder
(Peer reviewed; Journal article, 2020)Vortex interactions behind step cylinders with diameter ratio D/d = 2 and 2.4 at Reynolds number ( ReD ) 150 were investigated by directly solving the three-dimensional Navier–Stokes equations. In accordance with previous ... -
Vortex dynamics and flow patterns in a two-dimensional oscillatory lid-driven rectangular cavity
(Peer reviewed; Journal article, 2020)The vortex dynamics in a two-dimensional oscillatory lid-driven cavity with depth-to-width ratio 1:2 has been investigated, covering a wide range of Reynolds numbers and Stokes numbers where this flow is known to be in the ... -
Vortex Induced Fatigue Damage of a Steel Catenary Riser near the Touchdown Point
(Master thesis, 2013)In this thesis, the fatigue damage of a steel catenary riser was investigated, especially in the vicinity of the touchdown point.The steel catenary riser is a promising riser solution due to its simplicity and low cost. ... -
Vortex Induced Vibrations in Fish Farm Structural Elements
(Master thesis, 2015)Norway produces over 14 million meals of salmon every day. This corresponds to an annual value of close to 40 billion NOK. The world s continuous population increase will require a substantial increase in food production. ... -
Vortex induced vibrations of free span pipelines
(Doktoravhandlinger ved NTNU, 1503-8181; 2009:106, Doctoral thesis, 2009)Pipelines from offshore petroleum fields must frequently pass overareas with uneven seafloor. In such cases the pipeline may havefree spans when crossing depressions. Hence, if dynamic loads canoccur, the free span ... -
Vortex Induced Vibrations of Marine Risers
(Master thesis, 2012)SummaryThis Master s Thesis goal is to present fundamental physical aspects of Vortex Induced Vibrations (VIV) of marine risers, and outline methods for suppression of VIV. Main emphasis has been given to the use of strakes, ... -
Vortex Induced Vibrations of Pipelines With Non-Linear Seabed Contact Properties
(Chapter; Peer reviewed, 2016)A promising time domain model for calculation of cross-flow vortex induced vibrations (VIV) is under development at the Norwegian University of Science and Technology. Time domain, as oppose to frequency domain, makes it ... -
Vortex Induced Vibrations of Slender Marine Structures
(Master thesis, 2013)The main objective of this thesis is to study the behaviour of slender marine structures exposed to vortex induced vibrations (VIV). Especially the interaction between active response frequencies is important. This is done ... -
Vortex Induced Vibrations Of Slender Marine Structures: Inverse Analysis
(Master thesis, 2013)With the development of the offshore engineering and the increasing of water depth, VIV (vortex induced vibrations) becomes a big challenge of the design of slender marine structures. In engineering field, we use some ... -
Vortex Induced Vibrations on an ''Artificial Seabed'' for Support of a Floating Bridge
(Master thesis, 2015)The engineering company Reinertsen is planning a floating bridge with tunnel that will go across the Sognefjord. Reinertsen has designed what they call an "artificial seabed" to be used for anchoring of the floating bridge. ... -
Vortex system around a step cylinder in a turbulent flow field
(Peer reviewed; Journal article, 2021)The vortex system around the step surface of a step cylinder with a diameter ratio D/d=2 at Reynolds number (ReD) 3900 was investigated by directly solving the three-dimensional Navier–Stokes equations. Formation mechanisms ... -
VORTEX-INDUCED MOTIONS (VIM) OF A SEMI-SUBMERSIBLE FLOATING OFFSHORE WIND TURBINE
(Master thesis, 2024)Denne avhandlingen undersøker Vortex-Induced Motion (VIM)-fenomenet i semi-submersible flytende havvindmøller (FOWT), med spesielt fokus på 12 MW INO WINDMOOR-modellen. VIM, forårsaket av sykliske virvelshedningskrefter ... -
Vortex-induced vibrations of a vertical riser with time-varying tension
(Journal article; Peer reviewed, 2017)Numerical simulations of a vertical tensioned riser in a sheared flow are performed, where the riser top end oscillates sinusoidally in the vertical direction. The oscillating top-end motion causes tension variations and ... -
Wake behind a concave curved cylinder
(Journal article; Peer reviewed, 2018)The wake behind a quarter-of-ring concave curved cylinder is investigated in this paper by means of direct numerical simulations. The plane of curvature is aligned with the uniform incoming flow. We have appended straight ... -
Wake Effect Mitigation of Floating Offshore Wind Farms Combining Layout Optimization, Turbine Repositioning and Yaw-based Wake Redirection
(Master thesis, 2023)Floating wind turbines despite the potential to harness energy from deep offshore areas where higher average wind speeds face challenges in terms of competitiveness. One approach to raising the competitiveness of a wind ... -
Wake flow behind a curved cylinder
(Master thesis, 2014)This thesis reports the result of an experiment measuring the wake flow behind a curved circular cylinder at Re=3900 in water. The measurement technique used was Particle Image Velocimetry (PIV). The cylinder is a convex ... -
Wake Shielding Model Effect on Riser Dynamic Response
(Chapter, 2017)The paper provides a method to estimate the clearance between two flexible risers in tandem arrangement by taking into account the wake interference when subjected to a combined current plus waves flow. The wake interference ... -
Wake structures and vortex-induced forces of a controlled in-line vibrating circular cylinder
(Peer reviewed; Journal article, 2019)A two-dimensional numerical study was performed to investigate wake structures and fluid forces on a circular cylinder with prescribed vibrations in the in-line direction. Reynolds number was fixed at 500, and the SST k-w ... -
Wall Modeled Large Eddy Simulation of Viscous Flow on the BeVERLI Hill Geometry
(Master thesis, 2021)I denne masteroppgaven har vegg-modellert LES blitt brukt til å simulere den viskøse strømningen over BeVERLI hill geometrien. BeVERLI hill er en veggmontert «bump» som blir brukt i valideringsstudier av turbulente separerte ...