D.W. Lobitz, T. D. Ashwill, April 1986, Sandia National Laboratories
Aeroelastic effects impact the structural dynamic behavior of vertical axis wind turbines (VAWTs) 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 aero- elasticity 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...
Brian C. Owens and John E. Hurtado
Texas A&M University, College Station, Texas, 77843, USA
Joshua A. Paquette, Daniel T. Griffith, and Matthew Barone§
Sandia National Laboratories, Albuquerque, New Mexico, 87185, USA April 1986, Sandia National Laboratories
The availability of offshore wind resources in coastal regions makes offshore wind energy an attractive opportunity. There are, however, significant challenges in realizing offshore wind energy with an acceptable cost of energy due to increased infrastructure, logistics, and operations and maintenance costs. Vertical-axis wind turbines (VAWTs) are potentially ideal candidates for offshore applications, with many apparent advantages over the horizontal-axis wind turbine configuration in the offshore arena. VAWTs, however, will need to undergo much development in the coming years. Thus, the Offshore Wind ENergy Simulation (OWENS) toolkit is being developed as a design tool for assessing innovative floating VAWT configurations.
B C Owens and D T Griffith, June 2014, Sandia National Laboratories
A vertical-axis wind turbine (VAWT) rotor configuration offers a potential transformative technology solution that significantly lowers cost of energy for offshore wind due to its inherent advantages for the offshore market. However, several potential challenges exist for VAWTs and this paper addresses one of them with an initial investigation of dynamic aeroelastic stability for large-scale, multi-megawatt VAWTs. The aeroelastic formulation and solution method from the BLade Aeroelastic STability Tool (BLAST) for HAWT blades was employed to extend the analysis capability...
Torben Juul Larsen and Helge Aagaard Madsen, Technical University of Denmark, Department of Wind Energy, 2013
In this paper a method for reducing the complex three dimensional flow problem of a Vertical Axis Wind Turbine (VAWT) into a number of 2D problems. The specific focus is on the implementation into a full aeroelastic code including consideration of structural dynamics, dynamic inflow, tower shadow and dynamic stall properties, which is needed for a full load analysis relating to eg. certification of a VAWT turbine. Load comparison to measurements of simple tests a presented with fine results. Further on, principal load cases according to the IEC61400-1 are simulated for a fictitious 5MW VAWT turbine. The IEC61400-1 load cases, originally developed for Horizontal Axis Wind Turbines (HAWT's), are discussed regarding the application to VAWT's.
Dale Berg, September 2016, Sandia National Laboratories
This slide deck was present to Delft Technical University by Dale Berg who was a principal researcher of the Darrieus type VAWTs that Sandia National Laboratories worked on from the 1970s through the 1990s. It covers the history of Sandia's work on VAWTs including their efforts to develop validated aeroelastic modeling.