1. Grid Open Days all’Università di Palermo Palermo, 6-7.12.2007
Airfoils Characterization by means of CFD Simulations in GRID Environment
Prof. Ing. Rosario Lanzafame
Dipartimento di Ingegneria Industriale e Meccanica
Facoltà di Ingegneria – Università degli Studi di Catania
Viale A.Doria, 6 – Catania
Grid Open Days all’Università di Palermo
Palermo,

2. Blade Element Momentum Theory Drag and Lift Coefficients
Outline
Blade Element Momentum Theory
Drag and Lift Coefficients
Proposed Application
Results and Discussion
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3. Blade Element Momentum Theory
The BEM Theory is a 1-D mathematical theory based on bi-dimensional measurements of lift and drag airfoil coefficients able to evaluate forces and torque on wind turbines rotors
The BEM theory is widely used in fluid dynamics wind turbines design due to its good agreement with experience
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4. Blade Element Momentum Theory

5. Blade Element Momentum Theory
(7)

6. airfoil angle of attack
streamlines
wind speed
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7. Drag and Lift Coefficients
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8. Drag and Lift Airfoil Coefficients Evaluation

9. Lift Coefficient vs Angle of Attack

10. Drag Coefficient vs Angle of Attack

11. Airfoil characterization
Application Scheme
Send inputs
Application core
OPTIMIZER
USER
INTERFACE
PERFORMACE
Retrieve results
DESIGN
Airfoil
definition
Airfoil characterization
Airfoil database
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12. Airfoil Database
For each Reynolds number and angle of attack, the airfoil database contains:
Drag coefficient
Lift coefficient
Pressure fields
Velocity fields …
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13. VELOCITY CONTOURS (S809 airfoil)
Preliminary Results
VELOCITY CONTOURS (S809 airfoil)
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14. TOTAL PRESSURE CONTOURS (S809 airfoil)
Preliminary Results
TOTAL PRESSURE CONTOURS (S809 airfoil)
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15. Local Machine Running time
Processor: Intel(R) Core™ 2 Duo CPU GHz
RAM: MB
Operating System: Microsoft(R) Windows VISTA 32 bit
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16. GRID Running Time
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17. Total Running Time Local Machine: 494 min
Comparisons
Total Running Time Local Machine: 494 min
Total Running Time GRID: 382 min
Mean Variation: 22 %
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18. About 100 airfoils database Automatic mesh implementation on GRID
Future Developments
About 100 airfoils database
Automatic mesh implementation on GRID
Stall mathematical model implementation
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19. Any Questions ? Thank you very much for your kind attention!
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