IDEAS home Printed from https://ideas.repec.org/a/gam/jeners/v12y2019i19p3635-d270118.html
   My bibliography  Save this article

On-Bottom Stability of Umbilicals and Power Cables for Offshore Wind Applications

Author

Listed:
  • Guomin Ji

    (The Faculty of Engineering, Østfold University College, Kobberslagerstredet 5, 1671 Kråkerøy, Fredrikstad, Norway
    SINTEF Ocean, Marinteknisk Senter, Otto Nielsens vei 10, 7052 Trondheim, Norway)

  • Muk Chen Ong

    (Department of Mechanical and Structural Engineering and Materials Science, University of Stavanger, 4036 Stavanger, Norway)

Abstract

With the increase in offshore wind farms, the demands for umbilicals and power cables have increased. The on-bottom stability of umbilicals and power cables under the combined wave and current loading is the most challenging design issue, due to their light weight and the complex fluid–cable–soil interaction. In the present study, the methodology for dynamic lateral stability analysis is first discussed; and the reliable hydrodynamic load model and cable–soil interaction model based on large experimental test data are described in detail. The requirement of the submerged weight of a cable w s to obtain on-bottom stability is investigated for three types of soil (clay, sand and rock), using the finite element program PONDUS, and the results are w s , r o c k > w s , c l a y > w s , s a n d under the same load conditions. Several different aspects related to optimization design of the on-bottom stability are explored and addressed. There is a significant benefit for the on-bottom stability analysis to consider the reduction factors, due to penetration for clay and sand soil. The on-bottom stability is very sensitive to the relative initial embedment z 0 / D for clay and sand soil, due to the small diameter of the cables, and therefore, reliable prediction of initial embedment is required. In the energy-based cable–soil interaction model, the friction coefficient μ and the development of penetration affect each other and the total effect of friction force F f and passive resistance F r is complicated. The effect of the friction coefficient μ on the on-bottom stability is different from engineering judgement based on the Coulomb friction model. The undrained shear strength of clay is an important parameter for the on-bottom stability of umbilicals and cables. The higher the undrained shear strength of the clay, the larger the lateral displacement. Meanwhile, the submerged weight of sand has a minor effect on the lateral displacement of cables. The method used in the present study significantly improves the reliability of the on-bottom stability analysis of umbilicals and power cables for offshore wind application.

Suggested Citation

  • Guomin Ji & Muk Chen Ong, 2019. "On-Bottom Stability of Umbilicals and Power Cables for Offshore Wind Applications," Energies, MDPI, vol. 12(19), pages 1-20, September.
    • Handle: RePEc:gam:jeners:v:12:y:2019:i:19:p:3635-:d:270118
    as

    Download full text from publisher

    File URL: https://www.mdpi.com/1996-1073/12/19/3635/pdf
    Download Restriction: no
    File URL: https://www.mdpi.com/1996-1073/12/19/3635/
    Download Restriction: no
    ---><---

    Corrections

    All material on this site has been provided by the respective publishers and authors. You can help correct errors and omissions. When requesting a correction, please mention this item's handle: RePEc:gam:jeners:v:12:y:2019:i:19:p:3635-:d:270118. See general information about how to correct material in RePEc.

    If you have authored this item and are not yet registered with RePEc, we encourage you to do it here. This allows to link your profile to this item. It also allows you to accept potential citations to this item that we are uncertain about.

    We have no bibliographic references for this item. You can help adding them by using this form .

    If you know of missing items citing this one, you can help us creating those links by adding the relevant references in the same way as above, for each refering item. If you are a registered author of this item, you may also want to check the "citations" tab in your RePEc Author Service profile, as there may be some citations waiting for confirmation.

    For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: MDPI Indexing Manager (email available below). General contact details of provider: https://www.mdpi.com .

    Please note that corrections may take a couple of weeks to filter through the various RePEc services.

    IDEAS is a RePEc service. RePEc uses bibliographic data supplied by the respective publishers.