Welcome to the NWTC Design-Codes Publications page. Most of the papers you will find here are written by our Design-Codes Group and our subcontractors, but some are of general interest to wind turbine modelers. You can find documentation for our codes on our user's guides page.

Feel free to download any of our papers. You will need Adobe Acrobat Reader™ to read them. If you do not have the latest version of Acrobat Reader, go here.

If you would like to refer to any of our publications in your paper, please visit our references page.

• Lock_R&M_1014.pdf
  An Extension of the Vortex Theory of Airscrews with Applications to Airscrews of Small Pitch, Including Expermiental Results
  C.N.H. Lock, H. Bateman, H.C.H. Tiwsend
  Reports and Memoranda, No. 1014
  His Majesty's Stationery Office
  September 1925

• Glauert_R&M_1026.pdf
  The Analysis of Experimental Results in the Windmill Brake and Vortex Ring States of an Airscrew
  H. Glauert
  Reports and Memoranda, No. 1026
  His Majesty's Stationery Office
  February 1926

• Goldstein_VortexTheoryScrewPropellers_1929.pdf
  On the Vortex Theory of Screw Propellers
  Sydney Goldstein
  St. John's College, Cambridge
  January 1929

• WilsonLissaman_AppAeroOfWindPwrMach_1974.pdf
  Applied Aerodynamics of Wind Power Machines
  Robert E. Wilson
  Peter B. S. Lissaman
  Oregon State University
  May 1974

• WilsonLissamanWalker_AerodynamicPerformanceOfWindTurbines(1976).pdf
  Aerodynamic Performance of Wind Turbines
  Robert E. Wilson
  Peter B. S. Lissaman
  Stel N. Walker
  Oregon State University
  June 1976

• Swift_YawedFlow.pdf
  The Effects of Yawed Flow on Wind Turbine Rotors
  Andrew H. P. Swift, Jr.
  Doctor of Science Dissertation
  Washington University
  May 1981

• HibbsRadkey_BEM_Theory.pdf
  Small Wind Energy Conversion Systems (SWECS) Rotor Performance Model Comparison Study (UNPUBLISHED DRAFT)
  B. Hibbs
  R.L. Radkey
  Aerovironment, Inc.
  November 1981

• OstowariNaik_PostStall4415_Part1.pdf
  Post Stall Studies of Untwisted Varying Aspect Ratio Blades with an NACA 4415 Airfoil Section - Part I
  C. Ostowari
  D. Naik
  Texas A&M University
  Wind Engineering Vol. 8, No. 3, 1984, pp. 176–194

• SERI/STR-217-2559
  Post-Stall Wind Tunnel Data for NACA 44XX Series Airfoil Sections
  C. Ostowari
  D. Naik
  Texas A&M University
  January 1985

• OstowariNaik_PostStall44XX_Part2.pdf
  Post Stall Studies of Untwisted Varying Aspect Ratio Blades with NACA 44XX Series Airfoil Sections - Part II
  C. Ostowari
  D. Naik
  Texas A&M University
  Wind Engineering Vol. 9, No. 3, 1985, pp. 149–164

• PetersBoyd - Induced Velocities.pdf
  Finite-State Induced-Flow Model for Rotors in Hover and Forward Flight
  David A. Peters
  David Doug Boyd
  Cheng Jian He
  School of Aerospace Engineering
  Georgia Institue of Technology
  October 1989

• NREL/TP-257-4400
  Horizontal Axis Wind Turbine Post Stall Airfoil Characteristics Synthesization
  James L. Tangler
  SERI (now NREL)
  Cyrus Ostowari
  Texas A&M University
  June 1991

• PetersHe_InducedVelocities.pdf
  Correlation of Measured Induced Velocities with a Finite-State Wake Model
  David A. Peters
  Cheng Jian He
  School of Aerospace Engineering
  Georgia Institue of Technology
  July 1991

• NREL/TP-442-7728
  Data Preparation Requirements for Modeling Wind Turbines with ADAMS®
  Marshall L. Buhl, Jr.
  NREL-NWTC
  December 1994

• NREL Airfoil Families for HAWTs
  James L. Tangler
  NREL-NWTC
  Dan M. Somers
  Airfoils Incorporated
  1995

• PierceThesis.pdf
  Wind Turbine Load Prediction Using the Beddoes-Leishman Model for Unsteady Aerodynamics and Dynamic Stall
  Kirk Gee Pierce
  Dept. of Mechanical Engineering
  University of Utah
  August 1996

• NREL/CP-440-21670
  Effects of Turbulence on Power Generation for Variable-Speed Wind Turbines
  Eduard Muljadi
  C.P. (Sandy) Butterfield
  Marshall L. Buhl, Jr.
  NREL-NWTC
  November 1996

• NREL/CP-500-23975
  Wind Turbine Design Codes: A Preliminary Comparison of the Aerodynamics
  Marshall L. Buhl, Jr., Alan D. Wright, and James L. Tangler
  NREL-NWTC
  December 1997

• NREL/CP-500-24311
  Control Strategy for Variable-Speed, Stall-Regulated Wind Turbines
  E. Muljadi, K. Pierce, and P. Migliore
  NREL-NWTC
  April 1998

• MinnemaThesis.pdf
  Pitching Moment Predictions on Wind Turbine Blades Using the Beddoes-Leishman Model for Unsteady Aerodynamics and Dynamic Stall
  Jeffery Edward Minnema
  Dept. of Mechanical Engineering
  University of Utah
  June 1998

• NREL/TP-500-24919
  Dynamic Characterization of the AWT-26 Turbine for Variable Speed Operation
  Scott M. Larwood
  NREL-NWTC
  July 1998

• NREL/CP-500-25513
  A Progress Report on the Characterization and Modeling of a Very Flexible Wind Turbine Design
  Neil D. Kelley, Alan D. Wright, and Richard M. Osgood
  NREL-NWTC
  October 1998

• NREL/CP-500-25514
  Validation of a Model for a Two-Bladed Flexible Rotor System:
  Progress to Date
  Alan D. Wright, Neil D. Kelley, and Richard M. Osgood
  NREL-NWTC
  November 1998

• NREL/CP-500-25792
  Code Development for Control Design Applications
  Phase I: Structural Modeling
  Gunjit S. Bir and Michael Robinson
  NREL-NWTC
  November 1998

• NREL/CP-500-25787
  Predicting Ultimate Loads for Wind Turbine Design
  Peter Hauge Madsen
  Risø National Laboratory, Denmark
  Kirk Pierce & Marshall L. Buhl, Jr.
  NREL-NWTC
  November 1998

• NREL/CP-500-25983
  Operating Modes of a Teetered-Rotor Wind Turbine
  Gunjit S. Bir
  NREL-NWTC
  Karl Stol
  University of Colorado at Boulder
  November 1998

• NREL/SR-500-26173
  Design of a Tapered and Twisted Blade for the NREL Combined Experiment Rotor
  Phillipe Giguère and Michael S. Selig
  Department of Aeronautical and Astronautical Engineering
  University of Illinois at Urbana-Champaign
  April 1999

• NREL/CP-500-26244
  Non-Linear and Linear Model Based Controller Design for Variable-Speed Wind Turbines
  Maureen M. Hand and Mark J. Balas
  NREL-NWTC
  April 1999

• FAST_AD.pdf
  Technical and User's Manual for the FAST_AD Advanced Dynamics Code
  Robert E. Wilson
  Stel N. Walker
  Ping Hey
  Oregon State University
  May 1999

• SAND99-0089
  On the Fatigue Analysis of Wind Turbines
  Herbert J. Sutherland
  Sandia National Laboratories
  June 1999

• NREL/TP-500-26207
  Software Quality-Control Guidelines for Codes Developed for the NWTC
  Marshall L. Buhl, Jr.
  H. James Green
  NREL-NWTC
  June 1999

• NREL/TP-500-25540
  Variable-Speed Wind Turbine Controller Systematic Design Methodology:
  A Comparison of Non-Linear and Linear Model-Based Designs
  Maureen M. Hand
  NREL-NWTC
  July 1999

• NREL/CP-500-26322
  Control Method for Improved Energy Capture below Rated Power
  K. Pierce
  NREL-NWTC
  July 1999

• NREL/CP-500-27470
  Wind Turbine Design Codes: A Comparison of the Structural Response
  Marshall L. Buhl, Jr., Alan D. Wright, and Kirk G. Pierce
  NREL-NWTC
  January 2000

• NREL/CP-500-24791
  A Conservative Control Strategy for Variable-Speed Stall-Regulated Wind Turbines
  E. Muljadi, K. Pierce, and P. Migliore
  NREL-NWTC
  February 2000

• NREL/CP-500-27143
  Pitch-Controlled Variable-Speed Wind Turbine Generation
  Ed Muljadi and C.P. "Sandy" Butterfield
  NREL-NWTC
  February 2000

• setup.pdf
  Installing NWTC Design Codes on PCs Running Windows NT®
  Marshall L. Buhl, Jr.
  NREL-NWTC
  December 22, 2000
  103KB

• NREL/CP-500-28848
  FAST_AD Code Verification: A Comparison to ADAMS
  M.L. Buhl, Jr., A.D. Wright, and K.G. Pierce
  NREL-NWTC
  January 8-11, 2001

• NREL/TP-500-35109
  Evaluation of RCAS Inflow Models for Wind Turbine Analysis
  Jim Tangler, Gunjit Bir
  NREL-NWTC
  February 2004

• NREL/TP-500-34421
  Extrapolation of Extreme and Fatigue Loads Using Probabilistic Methods
  P.J. Moriarty, W.E. Holley, S.P. Butterfield
  NREL-NWTC
  November 2004

• FatLifeCalcByRFCycleCountingMeth_Ariduru.pdf
  Fatigue Life Calculation by Rainflow Cycle Counting Method
  Seçil Ariduru
  Graduate School of Natural and Applied Sciences
  Middle East Technical University
  December 2004

• NREL/CP-500-38456
  Wind Turbine Post-Stall Airfoil Performance Characteristics Guidelines for Blade-Element Momentum Methods
  James L. Tangler
  NREL-NWTC
  J. David Kocurek
  Computational Methodology Associates
  January 2005

• BuhlCodeSuitePaper.pdf
  The NWTC Design-Codes Suite: An Overview
  Marshall L. Buhl Jr.
  NREL-NWTC
  January 2005

• NREL/CP-500-36881
  AeroDyn Theory Manual
  Pat J. Moriarty
  NREL-NWTC
  A. Craig Hansen
  Windward Engineering
  January 2005

• GL_Report.pdf
  Evaluation Report: Design Codes FAST and ADAMS® for Load Calculations of Onshore Wind Turbines
  Andreas Manjock
  Germanischer Lloyd WindEnergie GmbH
  May 2005

• NREL/CP-500-36834
  A New Empirical Relationship between Thrust Coefficient and Induction Factor for the Turbulent Windmill State
  Marshall L. Buhl Jr.
  NREL-NWTC
  August 2005

• NREL/CP-500-39113
  A Comparison of Wind Turbine Aeroelastic Codes Used for Certification
  Marshall L. Buhl Jr.
  NREL-NWTC
  Andreas Manjock
  Germanischer Lloyd WindEnergie GmbH
  January 2006

• NREL/CP-500-40979
  Development and Verification of a Fully Coupled Simulator for Offshore Wind Turbines: Preprint
  Jason M. Jonkman
  Marshall L. Buhl Jr.
  NREL-NWTC
  January 2007

• NREL/CP-500-41714
  Loads Analysis of a Floating Offshore Wind Turbine Using Fully Coupled Simulation: Preprint
  Jason M. Jonkman
  Marshall L. Buhl Jr.
  NREL-NWTC
  June 2007

• dissertation_Larwood.pdf
  Dynamic Analysis Tool Development for Advanced Geometry Wind Turbine Blades
  Scott Michael Larwood
  U.C.-Davis
  2009

• Paper
  Presentation
  Necessity for Using Nonlinear Structural Analysis in Designing Blades
  Kyle K. Wetzel
  Wetzel Engineering, Inc.
  May 7, 2009