Open AccessSite‐specific variability of load extremes of offshore wind turbines exposed to hurricane risk and breaking waves
Author(s) -
Hallowell S.,
Myers A. T.
Publication year - 2017
Publication title -
wind energy
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.743
H-Index - 92
eISSN - 1099-1824
pISSN - 1095-4244
DOI - 10.1002/we.1996
Subject(s) - offshore wind power , marine engineering , submarine pipeline , environmental science , wind power , wind engineering , wind wave , breaking wave , geology , meteorology , engineering , turbine , seismology , oceanography , geography , aerospace engineering , physics , wave propagation , electrical engineering , quantum mechanics
Much of the US offshore wind energy resource is located in shallow water off the Atlantic coast, which is exposed to both hurricanes and breaking waves. Current practice in offshore wind turbine (OWT) design is to realize a target structural reliability by amplifying loads using fixed load factors that do not vary with structural or site characteristics. Given that variability in both hurricane conditions and breaking waves is structure‐ and site‐specific, the structural reliability of OWTs may vary significantly from site to site if fixed load factors are used. To understand the implications of this situation, there is a need to compare the numerical values of fixed load factors with those calculated using methods that prescribe structure‐specific and site‐specific load amplification that reflects variability in long‐term conditions. In this paper, site‐specific load amplification is considered for four Atlantic coast locations and four water depths per location and then compared with fixed load factors commonly used in the design of OWTs. The study shows that decreasing water depth and increasing hurricane exposure tend to increase the required load amplification for consistent structural reliability. Another influential factor is the mean return period at which impact loads due to breaking waves begin to dominate the loading. Copyright © 2016 John Wiley & Sons, Ltd.