1. H.A.W.T. Development Prototype and Testing - Final Report
Vortex Wind Systems
Group M9
April 1, 2014

2. INTRODUCTION Team members Supervisors Jeremy Tibbo Dr. Sam Nakhla
Dan Follett
Scott Guilcher
Supervisors
Dr. Sam Nakhla
Dr. Kevin Pope

3. Agenda Project Definition Past Accomplishments Optimization
Theoretical Power Output
Solid Mechanics
Finite Element Analysis
Prototype Model
Experimental Results
Conclusion

4. Project Definition Design of a small wind turbine to:
Power a cottage based on light, radio and TV and fridge based on Power Evaluation
52 weekends per year
Have a robust design that is optimized for Newfoundland wind characteristics

5. Past Accomplishments – Module 1
Project Definition
Environmental Analysis
Testing Options
Project Management Plan
Tool Evaluation
Market Analysis
Prototyping methods

6. Past Accomplishments – Module 2
Blade Design Theory
Design Considerations
Airfoil Polar Data Evaluation
Blade Design Analysis

7. Blade Design Theory Prop-ID Element/Momentum Theory Iterative Process
Stall Regulated Turbines
Tapered Blade Design

8. Airfoil Polar Data Evaluation
Airfoil Selection and Evaluation
Selection Caveats
Root Airfoil S814
Mid-Span Airfoil S812
Tip Airfoil S813

9. Design Considerations
Betz Law
Justification for 3 Blades
Theoretical Blade Length
Theoretical Power Output/Demand

10. Blade Design Analysis Geometry Performance Analysis Solid Mechanics
Normalized chord and twist distribution
Rotor Radius: 3.5 feet
Preliminary Design Sketch

11. Fabrication & Testing Phase - Module 3
Step 1 Optimization
Step 2
Solid Mechanics & FEA
Step 3
Prototyping & Fabrication
Step 4
Testing
Step 5
Going Forward

12. Optimization
Adjusted focus from maximum power output at low wind speeds to higher annual kWh
Changed blade geometry to match Weibull wind distribution

13. Theoretical Power Output
Total power: 4620 kWh
40% capacity: 1848 kWh

14. Preliminary Stress Calculations - Blade
Using the maximum coefficient of lift and drag:
Two moments will occur in this stress evaluation while treating the blade as a beam:
About the Y-axis in a negative manner
About the Z- axis in the positive direction

15. Preliminary Stress Calculations - Blade
Using the lift, drag forces and moments calculated:
Therefore the “ballpark” stress expected was:
1.297 MPa

16. Finite Element Analysis (FEA)
To ensure safety and reliability while testing, FEA was performed on the blades
Material: ABS-M30 Plastic
Yield Strength: 36,000,000 Pa
Maximum Lift Force: 140N/m2
Maximum Drag Force: 40N/m2
Do to the size, the aerodynamic moment was neglected during analysis
Fatigue was evaluated as shown on the right. No issues found

17. Finite Element Analysis
Von Misses Stress Results
Maximum: 1,149,901.8 Pa
Displacement (mm)
Maximum: mm
Safety Factor: XXXXXXXXXXXX

18. Prototype Model Prototype parts: 1. Shaft – ½” tapered shaft
2. Bearing and seat
3. Generator
4. Nacelle with end cap
5. Rotor hub
6. Blades
Design philosophy behind prototype:
Simple to assemble
Strong and reliable
Cost effective
Fit in the wind tunnel 6 4 2 1 3 5

19. Experimental Results Measured at 10m/s – theoretical peak output
Other losses:
Surface finish
Bearing friction
Alignment

20. Conclusion Blade design optimized to meet estimated power requirements
Blade structural requirements met
Prototype operated as predicted
Peak power observed is acceptable
Recommendations:
Include gears to reduce TSR and increase driveshaft RPM
Implement full scale prototype in rural setting to evaluate and compare power output

21. Questions?