Windpower Engineering & Development

  • Home
  • Articles
    • Most recent posts
    • News
    • Featured
  • Resources
    • Digital issues
    • Podcasts
    • Suppliers
    • Webinars
    • Events
  • Videos
  • 2025 Leadership
    • 2024 Winners
    • 2023 Winners
    • 2022 Winners
  • Magazine
  • Advertise
  • Subscribe

What happens to sub-structures & cables on the seafloor? Sandia examines

By Paul Dvorak | July 23, 2014

Sandia fig 3 Sediment deposition

Sediment deposition and erosion around a single pile with 3-D representation (flow is left to right).

A key risk driver in Offshore Wind (OW) projects is the potentially detrimental interaction between OW sub-structures and cables, and the seafloor. In previous years Sandia National Laboratories (SNL) developed methods for the evaluation of regional sediment stability with the use of combined wave, circulation, and sediment dynamics modeling. Knowledge of sediment stability not only in the vicinity of an offshore wind deployment, but all the way to the shore line can help optimize array layouts and cable routes by identifying seabed locations that are highly volatile.

The present work is focused on evaluating the use of these same tools to assess scour around offshore wind foundations. Combining the knowledge of regional sediment stability with local scour potential can ultimately help lower project risk and costs because foundations may be over or under designed to compensate for lack of accurate characterization of local sediment dynamics.

Sandia National Laboratories (SNL) is testing, validating, and calibrating the SNL-EFDC model for use in seafloor scour studies. The scour cases are being validated with laboratory and field measurements to provide a robust modeling tool for scour assessment. At present, unidirectional scour cases around multiple pile configurations have been developed and are being compared with the results from analytic and laboratory scour test cases. Additional cases that include wave action will be the focus of future efforts.

Sandia fig 4 sediment deposition around a tandem pileThus far, scour patterns and erosion rates have been analyzed around three distinct pile configurations consisting of a single pile, two pilings oriented parallel to the flow direction, and three pilings in a triangle pattern.   Curvilinear grids were utilized to allow for greater resolution around the piling than at the model edges to improve computation time. This also allowed for the grid to follow the curvature of the piling, reducing grid stair-stepping and associated potential numerical instabilities.

Figures 3, 4 above, and 5 below, show the scour and deposition patterns around the one, two, and three pile scenarios, respectively. For greater clarity, pick on each image.  For the single and tandem piling scenarios, an additional three-dimensional representation of scour around the piles is also presented.  Work is ongoing to compare the scour predictions with analytical and test data, including determining the sensitivity of the predictions to grid parameters.  Ultimately, development of tools to accurately assess sediment dynamics will guide more rigorous and robust standards to support the offshore wind industry.

Sandia fig 5 sediment erosion dep around a three pilings

Jesse Roberts, (505) 844-5730
Sandia
Sandia.gov


Filed Under: News, Offshore wind
Tagged With: Sandia
 

About The Author

Paul Dvorak

Related Articles Read More >

US government allows Empire Wind offshore project to resume construction
Richardson Electronics to deliver pitch energy modules to TransAlta wind fleets
Equinor halts work on Empire Wind offshore project after federal government order
ARESCA wants input on offshore wind standards

Podcasts

Wind Spotlight: Looking back at a year of Thrive with ZF Wind Power
See More >

Windpower Engineering & Development Digital Edition

Digital Edition

Browse the most current issue of Windpower Engineering & Development and back issues in an easy to use high quality format. Clip, share and download with the leading wind power engineering magazine today.

Windpower Engineering & Development
  • Wind Articles
  • Solar Power World
  • Subscribe to Windpower Engineering
  • About Us/Contact Us

Copyright © 2025 WTWH Media LLC. All Rights Reserved. The material on this site may not be reproduced, distributed, transmitted, cached or otherwise used, except with the prior written permission of WTWH Media
Privacy Policy | Advertising

Search Windpower Engineering & Development

  • Home
  • Articles
    • Most recent posts
    • News
    • Featured
  • Resources
    • Digital issues
    • Podcasts
    • Suppliers
    • Webinars
    • Events
  • Videos
  • 2025 Leadership
    • 2024 Winners
    • 2023 Winners
    • 2022 Winners
  • Magazine
  • Advertise
  • Subscribe