Browsing Institutt for marin teknikk by Title
Now showing items 3354-3373 of 3410
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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 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 ... -
Water Entry of Freefall Wedges-Wedge Motions and Cavity Dynamics
(Doktoravhandlinger ved NTNU, 1503-8181; 2014:144, Doctoral thesis, 2014)When a free falling object enters a free surface of water, it may go through four successive phases: impact, flow separation from the body surface, creation and pinch-off of the cavity above the body, and oscillation of ... -
Wave and Current Effects on Floating Fish Farms
(Journal article; Peer reviewed, 2018)The paper is partly a review on hydrodynamic and structural aspects of fish farms. In addition, new numerical results are presented on the stochastic behavior of bending stresses in the floater of a realistic net cage in ... -
Wave conditions encountered by ships—A report from a larger shipping company based on ERA5
(Peer reviewed; Journal article, 2021)This study reports about the wave conditions encountered by the fleet of Maersk Line. Herein, wave conditions refer to integral wave parameters in terms of significant wave height, zero-upcrossing period, and wave direction ... -
Wave Conditions for Offshore Wind Turbine Foundations in Intermediate Water Depths
(Master thesis, 2012)In this thesis, the effects on regular waves when propagating from deep to shallow water have been investigated, assuming linear wave theory. The effects of shoaling, refraction, reflection and diffraction have been studied. ... -
Wave dispersion in moderate channel turbulence
(Peer reviewed; Journal article, 2023)We study channel turbulence by interpreting its vorticity as a random sea of ocean wave packet analogues. In particular, we investigate the ocean-like properties of vortical packets applying stochastic methods developed ... -
Wave disturbance rejection for monopile offshore wind turbines
(Journal article; Peer reviewed, 2019)The dimensions of offshore wind turbine (OWT) support structures are governed by fatigue considerations. For 6‐ to 10‐MW OWTs, wave loads are often dominating in terms of fatigue utilization. The present work proposes a ... -
Wave induced effects on floaters of aquaculture plants
(Doctoral Theses at NTNU, 1503-8181; 2010:20, Doctoral thesis, 2010)The main objective of this work is to study wave loads on floaters of fish farms. Several incidents of major fish escapes due to structural collapse of fish farms in harsh weather have motivated this study, as a step towards ... -
Wave induced effects on floaters of aquaculture plants
(Doctoral Theses at NTNU, 1503-8181; 2010:20, Doctoral thesis, 2010)The main objective of this work is to study wave loads on floaters of fish farms. Several incidents of major fish escapes due to structural collapse of fish farms in harsh weather have motivated this study, as a step towards ... -
Wave induced motions of two ships advancing on parallel course
(Doktoravhandlinger ved NTNU, 1503-8181; 64, Doctoral thesis, 2002)Under way replenishment between two ships is a critical operation, and accidents have been reported. Hydrodynamic interaction between the hulls may influence the forces and the motions of the vessels, and both manoeuvring ...