Design of a small horizontal axis wind turbine, HAWT

1. Design of a small horizontal axis wind turbine, HAWT

2. Design parameters • Power Output, P: 300 W • Wind velocity , c: 8 m/s • Tip Speed Ratio, TSR: 5 • Assumed efficiency, h: 30 % • Number of blades, z: 2 • Wing profile: NACA 23015 • Angle of attack, a: 8o • Lift coefficient, CL: 0,8 • Drag coefficient, CD: 0,01

3. Radius of the turbine D Where: A = Area [m2] c = Wind velocity [m/s] h = Efficiency [ - ] P = Power [W] r = Density [kg/m3] R = Radius [m]

4. Speed of the turbine w Where: c = Wind velocity [m/s] n = Speed [rpm] w = Angular velocity [rad/s] R = Radius [m]

5. dA dr r Power through a section of the turbine blade

6. Torque force, dFT from a section of the turbine blade dFT dA dr r

7. Wing profile Chord Length, Lchord

8. FL FD a v LChord 4 Where: A = Area [m2] a = Angle of attack [degrees] CD = Drag Coefficient [ - ] CL = Lift Coefficient [ - ] FD = Drag Force [N] FL = Lift Force [N] LChord = Chord Length [m] r = Density [kg/m3] V = Relative velocity [m/s]

9. Peripheral velocity Wind velocity = c Relative velocity = V V u c u w

10. FL FD u = w·r a q v c

11. F FL FD F a u = w·r q F v u c v c

12. F u v c F a u = w·r q F v FL(Torque) FL c FD FD(Torque)

13. F a u = w·r q F v FT FL c FD

14. FT v

15. u F v c Chord Length, Lchord Lchord

16. Output data