dc.contributor.author | Killingstad, Simen | |
dc.contributor.author | Edfelt, Henrik | |
dc.date.accessioned | 2014-09-17T11:50:35Z | |
dc.date.available | 2014-09-17T11:50:35Z | |
dc.date.copyright | 2014 | |
dc.date.issued | 2014-09-17 | |
dc.identifier.uri | http://hdl.handle.net/11250/220267 | |
dc.description.abstract | This master’s thesis describes the evaluation of a semi-submersible offshore wind turbine concept
designed by Dr. techn. Olav Olsen. The main purpose of this evaluation is to contribute towards the
development and verification of the numerical simulation code 3DFloat. During 2013 a series of
experimental tests were performed on a scaled down model of the OO Star Wind Floater. The
experiments were carried out at a wave tank located at Ecole Centrale de Nantes, in France.
During the initial stage of this project our focus was mainly upon coupling 3Dfloat with theoretical
knowledge. When the experimental test results arrived our minds were set on understanding the
different test regimes, having boundary conditions for 3Dfloat in mind.
Based on analysis of the test results and theoretical considerations 3Dfloat is setup to simulate a
specific set of experiments. A main goal has been to recreate the physical movements of the
platform represented in the different tests with one single setup. This required altering a series of
coefficients and variables in a predefined input-file.
During the final stages of this project a simulation setup able to recreate “free decay” tests was
achieved. The heave-period was described by an added mass coefficient of 2.65. Our specific setup
does not produce simulations with good agreement for cases with wind and wave loading. This
seems to be due to a mismatch between global quadratic damping and “Morison” drag.
An axial “Morison” drag of 4 is likely to be too sparse. In the feature the damping ratio needs closer
inspection. Verification of the mooring system and some alterations to the RNA-geometry is
advised. With these subjects in mind a higher simulation quality should be reached. | nb_NO |
dc.language.iso | nob | nb_NO |
dc.publisher | Norwegian University of Life Sciences, Ås | |
dc.subject | Realfag | nb_NO |
dc.title | Analyse av halvt nedsenkbar offshore vindturbin | nb_NO |
dc.title.alternative | Analysis of a Semi Submersible Offshore Wind turbine | nb_NO |
dc.type | Master thesis | nb_NO |
dc.subject.nsi | VDP::Mathematics and natural science: 400::Information and communication science: 420::Simulation, visualization, signal processing, image processing: 429 | nb_NO |
dc.source.pagenumber | 111 | nb_NO |
dc.description.localcode | M-MPP | nb_NO |