Wind Energy Handbook. Michael Barton Graham
rotational speed at low wind speeds...Figure 3.58 Effect on extracted power of blade pitch set angle.Figure 3.59 Pitching to feather power regulation requires large changes of p...Figure 3.60 Power vs wind speed curve from the binned measurements of a thre...Figure 3.61 Comparison of measured and theoretical performance curves.Figure 3.62 Measured raw results of a three blade wind turbine.Figure 3.63 C P ‐λ curve for a design tip speed ratio of 7 at 7 m/...Figure 3.64 K P ‐1/λ curve for a fixed‐speed, stall‐regulated turb...Figure 3.65 Power vs wind speed.Figure 3.66 Energy capture curve.Figure 3.67 Energy capture curve for numerical integration.Figure 3.68 Power vs wind speed for variable‐speed turbine.Figure 3.69 NREL aerofoil profiles for large blades.Figure 3.70 The Risø‐A series of aerofoil profiles.Figure 3.71 The Risø‐P series of aerofoil profiles.Figure 3.72 The Risø‐B series of aerofoil profiles.Figure 3.73 The Delft University series of aerofoil profiles.Figure 3.74 Flat‐back aerofoil derived from DU‐97‐W‐300.Figure 3.75 VGs on a blade suction surface. (Flow is from right to left.)Figure 3.76 Flaps and similar acting devices: (a) conventional trailing edge...Figure 3.77 Lift coefficient vs jet momentum coefficient for jet circulation...Figure 3.78 Low noise aerofoil family: (a) DTU‐LN1xx, (b) DTU‐LN2xx, and (c)...Figure 3.79 Diagram of serrated trailing edge for reduction of TE noise.Figure A3.1 Flow past a streamlined body.Figure A3.2 Boundary layer showing the velocity profile.Figure A3.3 Separation of a boundary layer.Figure A3.4 Separated flow past a flat plate.Figure A3.5 Laminar and turbulent boundary layers.Figure A3.6 Variation of C d with Re for a long cylinder.Figure A3.7 Flow past a rotating cylinder.Figure A3.8 Circulatory flow round a rotating cylinder.Figure A3.9 Flow past an aerofoil at a small angle of attack: (a) inviscid f...Figure A3.10 The pressure distribution around the NACA0012 aerofoil at α...Figure A3.11 The pressure distribution around the NACA0012 aerofoil at α...Figure A3.12 Stalled flow around an aerofoil.Figure A3.13 C l − α curve for a symmetrical aerofoil.Figure A3.14 Variationof C d with α for the NACA0012 aerofoil.Figure A3.15 Lift/drag ratio variation for the NACA0012 aerofoil.Figure A3.16 Variation of the drag coefficient with Reynolds number at low a...Figure A3.17 Variation of the drag and lift coefficients with Reynolds numbe...Figure A3.18 The profile of the NACA4412 aerofoil.Figure A3.19 Classification of the NACAXXXX aerofoil range.Figure A3.20 The characteristics of the NACA4412 aerofoil for Re = 1.5·10...
5 Chapter 4Figure 4.1 A wind turbine yawed to the wind direction.Figure 4.2 Deflected wake of a yawed turbine and induced velocities.Figure 4.3 Power coefficient variation with yaw angle and axial flow factor....Figure 4.4 Velocities and lift and induced drag forces on an autogyro in fas...Figure 4.5 Velocities normal to the yawed rotor.Figure 4.6 The deflected vortex wake of a yawed rotor showing the shed vorti...Figure 4.7 A yawed rotor wake without wake expansion.Figure 4.8 Plan view of yawed actuator disc and the skewed vortex cylinder w...Figure 4.9 Average induced velocities caused by a yawed actuator disc.Figure 4.10 Maximum power coefficient variation with yaw angle, comparison o...Figure 4.11 Axis system for a yawed rotor.Figure 4.12 Flow expansion function variation with radial position and skew ...Figure 4.13 Azimuthal and radial variation of horizontal (v) and vertical (w Figure 4.14 Flow expansion functions for one, two and three blade rotors by ...Figure 4.15 Approximate flow expansion functions for two and three blade rot...Figure 4.16 Øye's curve fit to Coleman's flow expansion function.Figure 4.17 Flow expansion causes a differential angle of attack.Figure 4.18 The velocity components in the plane of a blade cross‐section.Figure 4.19 Azimuthally averaged induced velocity factors for the Delft turb...Figure 4.20 Component velocities, normalised with wind speed, at 30° of yaw....Figure 4.21 Angle of attack variation at 30° of yaw.