Wind Turbine Final Report
WindTER – Wind Turbine Energy Resources
Kristina Monakhova – Program Manager
Elizabeth Yasuna – Executive Director
Dominick Farina – Business Development
Kyle Zalud – Technical Lead
EAS 140 D2-E, Zack Bauer, Nikita Ranjit Goraksha
Project Objectives
Purpose: Design efficient wind
turbines for small and large scale
applications
Goals:
• Build and improve a wind turbine
• Strive for continuous improvement
• Create a scientific foundation for
future improvements/innovations
• Focus on simplcity and reliability
Source: http://learn.kidwind.org/sites/default/files/windturbinebladedesign.ppt
Background Research - Design
Factors for Wind Turbines
•Number
of blades
•Angle of blades
•Shape of blades
•Blade Twist
•Blade Length
•Blade materials
•Generator
•Gear
ratios
•Oil/Lubricant used
•Height of tower
•Rotational Speed
Initial Build - Design
• Blades
▫
▫
▫
▫
▫
3
Balsa wood material
Flat
Roughly 30° tilt
Attached to single
wooden dowel with duct
tape
• Gears: largest and smallest
• Base: provided, no
support structure
Initial Build - Performance
max Voltage: 3.78V
max Current: 7mA
max Power: .026W
Bulb used: LED (lit)
Overview of Design Rationale
Design Factor
Possible Influences on Performance
Configurations for Experimentation
Real World
Testable
in Model
Research
Physical Law
Exp. 1 –
Blade shape
Exp. 2 - #
of blades
Exp. 3 – Blade
Angles
Exp. 4 – Type of
Blades
Number of
blades
yes
More = greater weight, solidity
 less speed, more torque
fewer  more speed, less
inertia
Solidity = # of blades *
area of blade / total
swept area
Baseline (3)
2, 3, 4
Baseline (3)
Baseline (3)
Angle of
Blades
yes
Affects angle of attack –
certain tilt to capture more
wind
Lift to Drag Ratio=
(blade area)(net
pressure)/(.5xDrag
coefficient × mass
density×area×velocity2),
Baseline (30)
Baseline
level (30)
0, 15, 30, 45
Baseline (15)
Shape of
blades
yes
Narrower at ends, airfoil
shape to maximize lift and
minimize drag
Lift to Drag Ratio=
(blade area × net
pressure)/(1/2 ×Drag
coefficient × mass
density×area×velocity^2
Rectangular,
air foil
Baseline
level (air
foil)
Baseline (air
foil
Baseline (air foil)
Blade twist
yes
Twisted down length to
maintain angle of attack
Lift to Drag Ratio=
(blade area)(net
pressure)/(.5xDrag
coefficient × mass
density×area×velocity2),
Baseline level
(none)
Baseline
level
(none)
Baseline level
(none)
Baseline level
(none)
Blade
length
yes
Longer blade increases
swept area, but increase
weight
Lift to Drag Ratio=
(blade area)(net
pressure)/(.5xDrag
coefficient × mass
density×area×velocity2),
Power in wind :
P=.5ρ(Πr2)v3
Baseline level
Baseline
level
Baseline level
Baseline level (some
variation)
Blade
material
yes
Lighter = accelerate rapidly,
heavier = more stable
Rotational Inertia,
I=.5mr2 , I = 1/12 ML2
+M(L/2)2
Basswood
Balsa
wood
Balsa wood
Balsa wood,
posterboard,
corrugated plastic,
basswood
Gear ratio
yes
Larger gear ratio = more
speed, less torque, more
resistive torque
Ressitive Torque = force
× Radius, rotational
speed transfer: rlωl=rsωs
Baseline
(largest)
Baseline
(largest)
Baseline
(largest)
Baseline (largest)
Generator
no
Tower Height
no
Experiments – Blade Shape
Experiment 1 - Blade
Shape
Configurations: Rectangular,
Air foil
Configurations: Bulb: LED Motor: B1 Fan Distance: 8ft
3 blades, 30 degrees, balsawood, large gear ratio
Rectangular
Shape
Rectangular
Airfoil
Max Voltage
(V)
Max Current
(mA)
3.03
3.3
Power
Cut-in Time
(W)
RPM (s)
Airfoil
17 0.05151
80
3.5
20
0.066
100
Conclusions: Airfoil – maximize lift, minimize drag
3.5
Experiment - Number of
blades
Configurations:Experiment 1 - Number of Blades
Configurations: Bulb: LED Motor: B1 Fan Distance: 8ft
a
A
a
a
A
A
30 degrees, large gear ratio, balsawood blades, rectangular shape
Number of
Blades
2
Max Voltage
(V)
2 3.3
3 2.8
blades
4 2.1
Max Current
(mA)
30.7
25.7
315.0
blades
Power
Cut-in Time
(W)
RPM (s)
0.10131 110
3
0.07196 102
3.5
blades
0.0315 498
4
Conclusions: 2 blades 3 blades
Experiment - Angles of Blades
Configurations: 0 °,
15 °,vs.
302Blade
°,
45Angles
°Angle
Experiment
- Blade
Power
0.12 Configurations: Bulb: LED Motor: B1 Fan Distance: 8ft
0.1
Power (W)
0°
15°
2 blades, balsawood blades, large gear ratio, rectangular shape
0.08
Top
View
0.06
Angle
0.04
(degrees)
0.02
Max Voltage Max Current
(V)
(mA)
Power (W)
0
0 15
Side View
030
45
Cut-in Time
(s)
RPM
0
0
0
0
3.3
34.1
0.11253
81
3
20 19
30
0.05605
Blade Angles
4085
50 3
49
3.5
10
2.95
2.8
Conclusion: 15° is optimal
2.3
0.00644
Experiments – Blade Material
Configurations: Experiment 3 - Blade Material
Configurations: Bulb: LED Motor: B1 Fan Distance: 8ft
3 blades, 15 degrees, large gear ratio, airfoil shape
Max Voltage Max Current
Cut-in Time
Balsawood
Basswood
Material
(V)
(mA)
Power
(W)RPM (s)
Balsawood
2.8
18
0.0504
81
3.5
Posterboard
2
2.2
0.0044
92
3
Corrugated
Plastic
2.3
1.6 0.00368
90
3
Posterboard
Corrogated
Basswood
3.03
17 0.05151Plastic
80
3.5
Conclusions: basswood – more inertia
Final Improved Design
• Blades
▫
▫
▫
▫
▫
3
Bass wood material
Flat
Roughly 15° tilt
Attached to single wooden
dowel with wood glue and duct
tape
• Gears: largest and smallest
• Base: duct tape and poster
board support structure
Final Improved Design –
Rationale and Innovations*
• Blades – Basswood *
▫ Heavier
▫ Longer
▫ 15° tilt
• Base*
▫ stability
Results - Final Testing
Calculated Values: • 2.05Ws
• Power in wind: 2.7• 3V,
W .02A
• Turbine Efficiency:• 160rpm
▫ Relative to power available
in wind : 2.2%
▫ Relative to power available
at blades: 3.75%
• Rotational Speed of high
speed shaft: 1011rpm
Interpretations of results
•• Successful:
Why?
▫▫
▫▫
▫▫
Very
consistent
Blades
too long voltage
– larger than fan diameter
Fairly
Bladesconsistent
too heavycurrent/power
Kept
on spinning
No twist
to bladesafter 60s
• Unsuccessful
▫ Unbalanced
▫ Low
current
and power
Tip-Speed
Ratio:
3.5
▫ High cut-in time
Source: http://learn.kidwind.org/sites/default/files/windturbinebladedesign.ppt
Future Research
• Blade twist from root to tip
• Curved Hub to guide wind to
blades
• Different blade lengths for
variable wind speeds
• Different blade widths
Too long
Optimal
Too short
curved
Questions?