Efficiency of a VAWT with Airfoil Pitch Control - comsol.de fileEfficiency of a VAWT with Airfoil...
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Efficiency of a VAWT with Airfoil Pitch Control Junkun Ma 1 , Cris Koutsougeras 2 , Hao Luo 2 October 6, 2016 1 Sam Houston State University 2 Southeastern Louisiana University
Transcript of Efficiency of a VAWT with Airfoil Pitch Control - comsol.de fileEfficiency of a VAWT with Airfoil...
Efficiency of a VAWT with
Airfoil Pitch Control
Junkun Ma1, Cris Koutsougeras2, Hao Luo2
October 6, 2016
1Sam Houston State University
2Southeastern Louisiana University
VAWT and HAWT
VAWT: Vertical Axis Wind Turbine
HAWT: Horizontal Axis Wind Turbine
Advantages and Disadvantages
Advantages:
• Easier to install and maintain
• No need to point into the wind
• Low risk for human or birds
• Can be installed in urban area
Disadvantages:
• Stall start
• Low efficiency
• Dynamic stability: vibration and noise
• Pulsatory torque
VAWT with Pitch and Camber
Controls
Governing Equations
Low speed laminar flow: Navier – Stokes equations
High speed turbulent flow: k - e turbulent flow model
Force and Torque
Force：
Torque：
NACA 0012 Airfoil
COMSOL CFD Model
Velocity Field
Pressure Field
Torque at 300 Support Arm Angle
35000
37000
39000
41000
43000
45000
47000
49000
51000
0 20 40 60 80 100 120 140 160 180
To
rqu
e (
N)
Attack Angle (0)
Effects of Wind Speed
72000
74000
76000
78000
80000
82000
84000
0 20 40 60 80 100 120 140 160 180
To
rqu
e (
N)
Attack Angle (0)
5m/s
10m/s
15m/s
20m/s
Effects of Support Arm Angle
0.0
10000.0
20000.0
30000.0
40000.0
50000.0
60000.0
70000.0
80000.0
90000.0
0 20 40 60 80 100 120 140 160 180
Effects of Support Arm Angle
0.0
10000.0
20000.0
30000.0
40000.0
50000.0
60000.0
70000.0
80000.0
90000.0
0 20 40 60 80 100 120 140 160 180
Effects of Support Arm Angle
0.0
10000.0
20000.0
30000.0
40000.0
50000.0
60000.0
70000.0
80000.0
90000.0
0 20 40 60 80 100 120 140 160 180
Conclusions
• Torque with respect to the VAWT main rotor
shaft depends on wind angle of attack and
support arm angle
• Wind speed does affect the peak torque. But the
torque increase due to higher wind speed is
insignificant
• For the NACA 0012 airfoil, the torque always
peaks out at 90 degree angle of attack at any
given support arm angle
Future Work
• 2D multi-blades model
• 3D model to explore airfoil edge effect
• 3D multi-blades model
• Non-symmetric airfoil other than NACA 0012
Questions?
![Dynamic Stall on Airfoils Exposed to Constant Pitch-Rate ... Pap… · investigating pitch rate, Reynolds number, airfoil geometry and Mach number [4, 6] all seek to identify key](https://static.fdocuments.in/doc/165x107/5f4d418c5881a577222dc2c1/dynamic-stall-on-airfoils-exposed-to-constant-pitch-rate-pap-investigating.jpg)
