Aeroelastic effects in the structural dynamic analysis of vertical axis wind turbines

Lobitz, D W; Ashwill, T D

Title: Aeroelastic effects in the structural dynamic analysis of vertical axis wind turbines

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Abstract

Aeroelastic effects impact the structural dynamic behavior of vertical axis wind turbines (VAWRs) in two major ways. First, the stability phenomena of flutter and divergence are direct results of the aeroelasticity of the structure. Secondly, aerodynamic damping can be important for predicting response levels, particularly near resonance, but also for off-resonance conditions. The inclusion of the aeroelasticity is carried out by modifying the damping and stiffness matrices in the NASTRAN finite element code. Through the use of a specially designed preprocessor, which reads the usual NASTRAN input deck and adds appropriate cards to it, the incorporation of the aeroelastic effects has been made relatively transparent to the user. NASTRAN flutter predictions are validated using field measurements and the effect of aerodynamic damping is demonstrated through an application to the Test Bed VAWT being designed at Sandia.

Authors:: Lobitz, D W; Ashwill, T D

Publication Date:: Tue Apr 01 00:00:00 EST 1986

Research Org.:: Sandia National Labs., Albuquerque, NM (USA)

OSTI Identifier:: 5920567

Report Number(s):: SAND-85-0957
ON: DE86009542

DOE Contract Number:: AC04-76DP00789

Resource Type:: Technical Report

Country of Publication:: United States

Language:: English

Subject:: 17 WIND ENERGY; VERTICAL AXIS TURBINES; AERODYNAMICS; DAMPING; RESPONSE FUNCTIONS; STABILITY; FLUID MECHANICS; FUNCTIONS; MACHINERY; MECHANICS; TURBINES; TURBOMACHINERY; WIND TURBINES; 170602* - Wind Energy Engineering- Turbine Design & Operation

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                    Lobitz, D W, and Ashwill, T D. Aeroelastic effects in the structural dynamic analysis of vertical axis wind turbines.  United States: N. p., 1986. 
        Web.

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                    Lobitz, D W, & Ashwill, T D. Aeroelastic effects in the structural dynamic analysis of vertical axis wind turbines.  United States.

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                    Lobitz, D W, and Ashwill, T D. 1986.  
        "Aeroelastic effects in the structural dynamic analysis of vertical axis wind turbines".  United States.

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@article{osti_5920567,

  title        = {Aeroelastic effects in the structural dynamic analysis of vertical axis wind turbines},

  author       = {Lobitz, D W and Ashwill, T D},

  abstractNote = {Aeroelastic effects impact the structural dynamic behavior of vertical axis wind turbines (VAWRs) in two major ways. First, the stability phenomena of flutter and divergence are direct results of the aeroelasticity of the structure. Secondly, aerodynamic damping can be important for predicting response levels, particularly near resonance, but also for off-resonance conditions. The inclusion of the aeroelasticity is carried out by modifying the damping and stiffness matrices in the NASTRAN finite element code. Through the use of a specially designed preprocessor, which reads the usual NASTRAN input deck and adds appropriate cards to it, the incorporation of the aeroelastic effects has been made relatively transparent to the user. NASTRAN flutter predictions are validated using field measurements and the effect of aerodynamic damping is demonstrated through an application to the Test Bed VAWT being designed at Sandia.},

  doi          = {},

  url          = {https://www.osti.gov/biblio/5920567},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {Tue Apr 01 00:00:00 EST 1986},

  month        = {Tue Apr 01 00:00:00 EST 1986}

}

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