skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Downwind pre-aligned rotors for extreme-scale wind turbines

Journal Article · · Wind Energy
DOI:https://doi.org/10.1002/we.2092· OSTI ID:1364153
 [1];  [1];  [1];  [2];  [3];  [4]
  1. Univ. of Virginia, Charlottesville, VA (United States)
  2. Stanford Univ., Stanford, CA (United States)
  3. Univ. of Illinois at Urbana-Champaign, Urbana, IL (United States)
  4. National Renewable Energy Lab. (NREL), Golden, CO (United States)
+ Show Author Affiliations

Downwind force angles are small for current turbines systems (1-5 MW) such that they may be readily accommodated by conventional upwind configurations. However, analysis indicates that extreme-scale systems (10-20 MW) will have larger angles that may benefit from downwind-aligned configurations. To examine potential rotor mass reduction, the pre-alignment concept was investigated a two-bladed configuration by keeping the structural and aerodynamic characteristics of each blade fixed (to avoids a complete blade re-design). Simulations for a 13.2 MW rated rotor at steady-state conditions show that this concept-level two-bladed design may yield 25% rotor mass savings while also reducing average blade stress over all wind speeds. These results employed a pre-alignment on the basis of a wind speed of 1.25 times the rated wind speed. The downwind pre-aligned concept may also reduce damage equivalent loads on the blades by 60% for steady rated wind conditions. Even higher mass and damage equivalent load savings (relative to conventional upwind designs) may be possible for larger systems (15-20 MW) for which load-alignment angles become even larger. Furthermore, much more work is needed to determine whether this concept can be translated into a practical design that must meet a wide myriad of other criteria.

Research Organization:
National Renewable Energy Laboratory (NREL), Golden, CO (United States)
Sponsoring Organization:
USDOE Office of Energy Efficiency and Renewable Energy (EERE)
Grant/Contract Number:
AC36-08GO28308
OSTI ID:
1364153
Report Number(s):
NREL/JA-5000-68262
Journal Information:
Wind Energy, Vol. 20, Issue 7; ISSN 1095-4244
Publisher:
WileyCopyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 35 works
Citation information provided by
Web of Science

References (21)

System design of a wind turbine using a multi-level optimization approach journal July 2012
Experiments on Fairing Designs for a Wind Turbine Tower journal March 2016
Stochastic dynamic response analysis of a tension leg spar-type offshore wind turbine: Tension leg spar-type offshore wind turbine journal July 2012
Wake impacts on downstream wind turbine performance and yaw alignment: Wake impacts on turbine performance and yaw alignment journal March 2012
Aerodynamic and Structural Design of MultiMW Wind Turbine Blades beyond 5MW journal June 2007
A parametric study of coupled-mode flutter for MW-size wind turbine blades: Coupled-mode flutter of MW-size wind turbine blades journal May 2015
Multivariable control strategy for variable speed, variable pitch wind turbines journal July 2007
Assessment of the power reduction of wind farms under extreme wind condition by a high resolution simulation model journal August 2012
Current developments and future prospects of offshore wind and ocean energy journal February 2012
Integrated design of downwind land-based wind turbines using analytic gradients: Downwind wind turbines journal February 2016
Review of performance optimization techniques applied to wind turbines journal March 2015
Modelling and analysis of the flow field around a coned rotor: Flow Field around a Coned Rotor journal July 2001
Novel structural modeling and mesh moving techniques for advanced fluid-structure interaction simulation of wind turbines: FSI OF WIND TURBINES journal July 2014
The concept of a smart wind turbine system journal March 2012
Performance analysis of open and ducted wind turbines journal December 2014
Parametric Variations of a Coning Rotor Wind Turbine conference June 2012
Wind Turbine Design Cost and Scaling Model report December 2006
Structural Design and Analysis of a Segmented Ultralight Morphing Rotor (SUMR) for Extreme-Scale Wind Turbines conference September 2012
Definition of a 5-MW Reference Wind Turbine for Offshore System Development report February 2009
Design of a 2-D Fairing for a Wind Turbine Tower conference June 2013
Materials and Innovations for Large Blade Structures: Research Opportunities in WInd Energy Technology conference June 2012

Cited By (4)

Tower shadow induced blade loads for an extreme‐scale downwind turbine journal December 2019
Analytic analysis of load alignment for coning extreme‐scale rotors journal February 2020
Comparison between upwind and downwind designs of a 10 MW wind turbine rotor journal January 2019
System-level design studies for large rotors journal January 2019

Similar Records

Morphing Downwind-Aligned Rotor Concept Based on a 13-MW Wind Turbine
Journal Article · Fri Apr 01 00:00:00 EDT 2016 · Wind Energy (Chichester, England) · OSTI ID:1364153
+2 more
Downwind coning concept rotor for a 25 MW offshore wind turbine
Journal Article · Sun Apr 12 00:00:00 EDT 2020 · Renewable Energy · OSTI ID:1364153
+5 more
Active rotor coning for a 25 MW downwind offshore wind turbine
Journal Article · Thu Jun 02 00:00:00 EDT 2022 · Journal of Physics. Conference Series · OSTI ID:1364153
+5 more

Related Subjects

17 WIND ENERGY
downwind
extreme scale
load aligned
turbine
wind energy