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Title: Using Large-Eddy Simulations to Define Spectral and Coherence Characteristics of the Hurricane Boundary Layer for Wind-Energy Applications

Abstract

Offshore wind-energy development is planned for regions where hurricanes commonly occur, such as the USA Atlantic Coast. Even the most robust wind-turbine design (IEC Class I) may be unable to withstand a Category-2 hurricane (hub-height wind speeds >50 m s -1). Characteristics of the hurricane boundary layer that affect the structural integrity of turbines, especially in major hurricanes, are poorly understood, primarily due to a lack of adequate observations that span typical turbine heights (<200 m above sea level). To provide these data, we use large-eddy simulations to produce wind profiles of an idealized Category-5 hurricane at high spatial (10 m) and temporal (0.1 s) resolution. By comparison with unique flight-level observations from a field project, we find that a relatively simple configuration of the Cloud Model I model accurately represents the properties of Hurricane Isabel (2003) in terms of mean wind speeds, wind-speed variances, and power spectra. Comparisons of power spectra and coherence curves derived from our hurricane simulations to those used in current turbine design standards suggest that adjustments to these standards may be needed to capture characteristics of turbulence seen within the simulated hurricane boundary layer. To enable improved design standards for wind turbines to withstand hurricanes,more » we suggest modifications to account for shifts in peak power to higher frequencies and greater spectral coherence at large separations.« less

Authors:
ORCiD logo [1];  [2];  [3];  [4]
  1. Univ. of Colorado, Boulder, CO (United States)
  2. National Center for Atmospheric Research, Boulder, CO (United States)
  3. Univ. of Colorado, Boulder, CO (United States); National Renewable Energy Lab. (NREL), Golden, CO (United States)
  4. Univ. of Miami, FL (United States)
Publication Date:
Research Org.:
Univ. of Colorado, Boulder, CO (United States); National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org.:
USDOE; National Science Foundation (NSF)
OSTI Identifier:
1394113
Report Number(s):
NREL/JA-5000-68893
Journal ID: ISSN 0006-8314
Grant/Contract Number:
AC36-08GO28308; DGE-1144083
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Boundary-Layer Meteorology
Additional Journal Information:
Journal Volume: 165; Journal Issue: 1; Journal ID: ISSN 0006-8314
Publisher:
Springer
Country of Publication:
United States
Language:
English
Subject:
17 WIND ENERGY; hurricane boundary layer; large-eddy simulation; tropical cyclone; wind-turbine design

Citation Formats

Worsnop, Rochelle P., Bryan, George H., Lundquist, Julie K., and Zhang, Jun A.. Using Large-Eddy Simulations to Define Spectral and Coherence Characteristics of the Hurricane Boundary Layer for Wind-Energy Applications. United States: N. p., 2017. Web. doi:10.1007/s10546-017-0266-x.
Worsnop, Rochelle P., Bryan, George H., Lundquist, Julie K., & Zhang, Jun A.. Using Large-Eddy Simulations to Define Spectral and Coherence Characteristics of the Hurricane Boundary Layer for Wind-Energy Applications. United States. doi:10.1007/s10546-017-0266-x.
Worsnop, Rochelle P., Bryan, George H., Lundquist, Julie K., and Zhang, Jun A.. Thu . "Using Large-Eddy Simulations to Define Spectral and Coherence Characteristics of the Hurricane Boundary Layer for Wind-Energy Applications". United States. doi:10.1007/s10546-017-0266-x. https://www.osti.gov/servlets/purl/1394113.
@article{osti_1394113,
title = {Using Large-Eddy Simulations to Define Spectral and Coherence Characteristics of the Hurricane Boundary Layer for Wind-Energy Applications},
author = {Worsnop, Rochelle P. and Bryan, George H. and Lundquist, Julie K. and Zhang, Jun A.},
abstractNote = {Offshore wind-energy development is planned for regions where hurricanes commonly occur, such as the USA Atlantic Coast. Even the most robust wind-turbine design (IEC Class I) may be unable to withstand a Category-2 hurricane (hub-height wind speeds >50 m s-1). Characteristics of the hurricane boundary layer that affect the structural integrity of turbines, especially in major hurricanes, are poorly understood, primarily due to a lack of adequate observations that span typical turbine heights (<200 m above sea level). To provide these data, we use large-eddy simulations to produce wind profiles of an idealized Category-5 hurricane at high spatial (10 m) and temporal (0.1 s) resolution. By comparison with unique flight-level observations from a field project, we find that a relatively simple configuration of the Cloud Model I model accurately represents the properties of Hurricane Isabel (2003) in terms of mean wind speeds, wind-speed variances, and power spectra. Comparisons of power spectra and coherence curves derived from our hurricane simulations to those used in current turbine design standards suggest that adjustments to these standards may be needed to capture characteristics of turbulence seen within the simulated hurricane boundary layer. To enable improved design standards for wind turbines to withstand hurricanes, we suggest modifications to account for shifts in peak power to higher frequencies and greater spectral coherence at large separations.},
doi = {10.1007/s10546-017-0266-x},
journal = {Boundary-Layer Meteorology},
number = 1,
volume = 165,
place = {United States},
year = {Thu Jun 08 00:00:00 EDT 2017},
month = {Thu Jun 08 00:00:00 EDT 2017}
}

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