The Dimensioning Sea Loads (DIMSELO) project: Paper

Fabio Pierella, Henrik Bredmose, Jacobus B. De Vaal, Lene Eliassen, Jørgen Krokstad, Tor Anders Nygaard, Luca Oggiano, Roy Stenbro*

*Corresponding author for this work

    Research output: Contribution to journalConference articleResearchpeer-review

    261 Downloads (Pure)

    Abstract

    DIMSELO is a Competence Building for Industry project (KPN), granted by the Norwegian Research Council under the ENERGIX program, which ran from 2013 to 2017. The project’s objective was to quantify the consequences of using advanced sea loads modeling in integrated simulations of offshore wind turbines in shallow to intermediate waters. During the project, engineering hydrodynamics load and wave kinematics models of increasing complexity and fidelity were chosen from the literature and implemented. The effect of different model combinations on the substructure loads was was tested for three reference turbines: a DTU 10 MW rotor positioned on a monopile at a water depth of h = 25 m, on a second monopile at h = 35 m and on a jacket, also at h = 35 m. In this paper, the fatigue loads in a production case for the h = 25 m monopile was calculated via three different load models: the well-known Morison model, the Rainey nonlinear force model and the McCamy-Fuchs linear diffraction model. The models were coupled to kinematics coming both from linear irregular waves and second order irregular waves. The comparison showed that using the McCamy-Fuchs diffraction theory reduced the predicted fatigue damage by 15% with respect to a base case where the Morison load model was used. Nonlinear wave kinematics and nonlinear force models influenced the force calculations but did not alter the total fatigue damage, since the load cases with high wave steepness were less likely to happen. In parallel to the research on engineering models, detailed wave loads models were also developed during DIMSELO. By means of CFD, it was possible to reproduce experimental time series of wave loads on a cylinder induced by regular and irregular nearly-breaking waves. Also, a spectral solver for the fast resolution of the fully nonlinear diffraction problem was devised at DTU during DIMSELO. The solver, which showed encouraging results in the preliminary testing, can be coupled to any nonlinear kinematics solver to calculate the force on a cylinder retaining full nonlinearity and diffraction.
    Original languageEnglish
    Article number012037
    Book seriesJournal of Physics: Conference Series
    Volume1104
    Issue number1
    Number of pages14
    ISSN1742-6596
    DOIs
    Publication statusPublished - 2018
    Event15th Deep Sea Offshore Wind R&D Conference - Trondheim, Norway
    Duration: 17 Jan 201819 Jan 2018
    Conference number: 15
    https://iopscience.iop.org/article/10.1088/1742-6596/1104/1/011001

    Conference

    Conference15th Deep Sea Offshore Wind R&D Conference
    Number15
    Country/TerritoryNorway
    CityTrondheim
    Period17/01/201819/01/2018
    Internet address

    Fingerprint

    Dive into the research topics of 'The Dimensioning Sea Loads (DIMSELO) project: Paper'. Together they form a unique fingerprint.

    Cite this