الفهرس 
Wind Turbine Data
BLADE MODIFICATIONSOnly 14 pages are availabe for public view
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Abstract
Designers of modern wind turbines are more interested in stiffer and lighter blade designs as the growth of their size leads to reducing the production costs of electrical energy. The present work introduces a design analysis framework for wind turbines, using a combination of tools specially developed for this purpose. SNL 100-00 is taken as a reference wind turbine blade originally designed by Sandia National Labs. This blade is chosen as a case study to implement the proposed methodology. The first step in the methodology is to model the blade structure using two pre-processing python scripts: (1) Airfoil2BECAS to create a 2D finite element shell model for each cross-section and (2) Shellexpander to generate the input files which are needed by the cross-sectional analysis software BECAS. The cross-sectional properties of the glass fiber-epoxy composite wind turbine blade computed by BECAS are then used as input to the aeroelastic code HAWC2 to conduct aeroelastic analysis and simulate DLCs where HAWCStab2 is used for tuning the controller parameters. The results developed by the proposed methodology are validated against those published by Sandia National Laboratories. Close agreement is observed and hence the proposed methodology can be used to introduce design modifications to improve the blades characteristics. Modifications including (1) changing the slope of the shear webs and (2) the spacing between them are investigated showing good chance of improving the structural and inertial properties of the blade. To evaluate such modifications, comparison against baseline design is conducted using the following metrics: Flapwise and Edgwise loading, tip deflection and cross-sectional properties including: Flapwise and Egdewise bending stiffnesses, axial stiffness, torsional stiffness and mass density.
PSO algorithm is utilized to develop an automatic tool to design optimal structure of wind turbine blades. The developed code is used to solve a benchmark problem and results are validated against published results and also against results obtained using GA toolbox in MATLAB. Finally, the optimization code is combined with the blade’s analysis framework presented to find the optimal slope for the shear webs and the optimal spacing distribution. Three variants of the objective function are considered aiming to reduce the mass and increase the stiffness of the blade. The resulting optimized configuration increases the flapwise stiffness normalized by mass density by varying percentages along the span of the blade reaching up to 18% increase and life expectancy increase ranging between 10-75%. This increase is expected to be directly reflected on the blades cost.