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Title: Roughness Sensitivity Comparisons of Wind Turbine Blade Sections

Abstract

One explanation for wind turbine power degradation is insect roughness. Historical studies on insect-induced power degradation have used simulation methods which are either un- representative of actual insect roughness or too costly or time-consuming to be applied to wide-scale testing. Furthermore, the role of airfoil geometry in determining the relations between insect impingement locations and roughness sensitivity has not been studied. To link the effects of airfoil geometry, insect impingement locations, and roughness sensitivity, a simulation code was written to determine representative insect collection patterns for different airfoil shapes. Insect collection pattern data was then used to simulate roughness on an NREL S814 airfoil that was tested in a wind tunnel at Reynolds numbers between 1.6 x 10 6 and 4.0 x 10 6. Results are compared to previous tests of a NACA 63 3 -418 airfoil. Increasing roughness height and density results in decreased maximum lift, lift curve slope, and lift-to-drag ratio. Increasing roughness height, density, or Reynolds number results in earlier bypass transition, with critical roughness Reynolds numbers lying within the historical range. Increased roughness sensitivity on the 25% thick NREL S814 is observed compared to the 18% thick NACA 63 3 -418. Blade-element-momentum analysis was used tomore » calculate annual energy production losses of 4.9% and 6.8% for a NACA 63 3 -418 turbine and an NREL S814 turbine, respectively, operating with 200 μm roughness. These compare well to historical field measurements.« less

Authors:
 [1];  [1];  [2]
  1. Texas A & M Univ., College Station, TX (United States). Dept. of Aerospace Engineering
  2. Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Wind Energy Technologies Dept.
Publication Date:
Research Org.:
Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE)
OSTI Identifier:
1404826
Report Number(s):
SAND-2017-11288
657910
DOE Contract Number:
AC04-94AL85000
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
17 WIND ENERGY

Citation Formats

Wilcox, Benjamin J., White, Edward B., and Maniaci, David Charles. Roughness Sensitivity Comparisons of Wind Turbine Blade Sections. United States: N. p., 2017. Web. doi:10.2172/1404826.
Wilcox, Benjamin J., White, Edward B., & Maniaci, David Charles. Roughness Sensitivity Comparisons of Wind Turbine Blade Sections. United States. doi:10.2172/1404826.
Wilcox, Benjamin J., White, Edward B., and Maniaci, David Charles. 2017. "Roughness Sensitivity Comparisons of Wind Turbine Blade Sections". United States. doi:10.2172/1404826. https://www.osti.gov/servlets/purl/1404826.
@article{osti_1404826,
title = {Roughness Sensitivity Comparisons of Wind Turbine Blade Sections},
author = {Wilcox, Benjamin J. and White, Edward B. and Maniaci, David Charles},
abstractNote = {One explanation for wind turbine power degradation is insect roughness. Historical studies on insect-induced power degradation have used simulation methods which are either un- representative of actual insect roughness or too costly or time-consuming to be applied to wide-scale testing. Furthermore, the role of airfoil geometry in determining the relations between insect impingement locations and roughness sensitivity has not been studied. To link the effects of airfoil geometry, insect impingement locations, and roughness sensitivity, a simulation code was written to determine representative insect collection patterns for different airfoil shapes. Insect collection pattern data was then used to simulate roughness on an NREL S814 airfoil that was tested in a wind tunnel at Reynolds numbers between 1.6 x 106 and 4.0 x 106. Results are compared to previous tests of a NACA 633 -418 airfoil. Increasing roughness height and density results in decreased maximum lift, lift curve slope, and lift-to-drag ratio. Increasing roughness height, density, or Reynolds number results in earlier bypass transition, with critical roughness Reynolds numbers lying within the historical range. Increased roughness sensitivity on the 25% thick NREL S814 is observed compared to the 18% thick NACA 63 3 -418. Blade-element-momentum analysis was used to calculate annual energy production losses of 4.9% and 6.8% for a NACA 633 -418 turbine and an NREL S814 turbine, respectively, operating with 200 μm roughness. These compare well to historical field measurements.},
doi = {10.2172/1404826},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2017,
month =
}

Technical Report:

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