This work examines the effect of flow inclination on the performance of a stand-alone wind turbine and of wind turbines operating in the wakes of upstream turbines. The experimental portion of this work, which includes performance and flowfield measurements, is conducted in the ETH dynamically-scaled wind turbine test facility, with a wind turbine model that can be inclined relative to the incoming flow. The performance of the wind turbine is measured with an in-line torquemeter, and a 5-hole steady-state probe is used to detail the inflow and wake flow of the turbine. Measurements show that over a range of tip-speed ratios of 4–7.5, the power coefficient of a wind turbine with an incoming flow of 15 deg inclination decreases on average by 7% relative to the power coefficient of a wind turbine with a noninclined incoming flow. Flowfield measurements show that the wake of a turbine with an inclined incoming flow is deflected; the deflection angle is approximately 6 deg for an incoming flow with 15 deg inclination. The measured wake profiles are used as inflow profiles for a blade element momentum code in order to quantify the impact of flow inclination on the performance of downstream wind turbines. In comparison to the case without inclination in the incoming flow, the combined power output of two aligned turbines with incoming inclined flow decreases by 1%, showing that flow inclination in complex terrain does not significantly reduce the energy production.

References

References
1.
U.S. Energy Information Administration
,
2011
, “
International Energy Statistics
,” http://www.eia.gov/
2.
Global Wind Energy Council
,
2010
, “
Global Wind Report
,” http://www.gwec. net/
3.
Hau
,
E.
,
2006
,
Wind Turbines: Fundamentals, Technologies, Application, Economics
,
2nd ed.
,
Springer
,
New York
.
4.
Winkelmeier
,
H.
, and
Geistlinger
,
B.
,
2004
, “
Alpine Windharvest
,” Alpine Windharvest Partnership Network, Austria, Tech. Report No. A/I-2/3.1./5.
5.
Singh
,
A.
,
Chokani
,
N.
, and
Abhari
,
R. S.
,
2011
, “
Assessing Large-Scale, Economic Wind Energy Potential
,”
7th PhD Seminar on Wind Energy in Europe
, Delft, The Netherlands, Oct. 27-28.
6.
Kocer
,
G.
,
Mansour
,
M.
,
Chokani
,
N.
,
Abhari
,
R. S.
, and
Müller
,
M.
,
2011
, “
Full-Scale Wind Turbine Near-Wake Measurements Using an Instrumented UAV
,”
J. Sol. Energy Eng.
,
133
, p.
041011
.10.1115/1.4004707
7.
Kress
,
C.
,
Barber
,
S.
,
Chokani
,
N.
, and
Abhari
,
R. S.
,
2011
, “
Improved Modeling of Wakes: Experimental Study and Experimentally-Anchored Model
,”
Proceedings of the EWEA Offshore 2011 Conference, Amsterdam, November 29-December 1
.
8.
Jafari
,
S.
,
Chokani
,
N.
, and
Abhari
,
R. S.
,
2011
, “
Terrain Effects on Wind Flow: Simulations With an Immersed Boundary Method
,”
Proceedings of ASME Turbo Expo 2011
,
ASME
Paper No. GT2011-46240. 10.1115/GT2011-46240
9.
Barber
,
S.
,
Wang
,
Y.
,
Jafari
,
S.
,
Chokani
,
N.
, and
Abhari
,
R. S.
,
2011
, “
The Impact of Ice Formation on Wind Turbine Performance and Aerodynamics
,”
J. Sol. Energy Eng.
,
133
, p.
011007
.10.1115/1.4003187
10.
Barber
,
S.
,
Chokani
,
N.
, and
Abhari
,
R. S.
,
2011
, “
Effect of Wake Flow Non-Uniformity on Wind Turbine Performance and Aerodynamics
,”
Proceedings of ASME Turbo Expo 2011
,
ASME
Paper No. GT2011-46230. 10.1115/GT2011-46230
11.
Kress
,
C.
,
2011
, “
Development of a Wind Turbine Wake Model for Wind Farm Layout
,” M.S. thesis, ETH Zurich, Zurich, Switzerland.
12.
Jiménez
,
A.
,
Crespo
,
A.
, and
Migoya
,
E.
,
2010
, “
Application of a LES Technique to Characterize the Wake Deflection of a Wind Turbine in Yaw
,”
Wind Energy
,
13
, pp.
559
572
.10.1002/we.380
13.
Rwigema
,
M. K.
,
2010
, “
Propeller Blade Element Momentum Theory With Vortex Wake Deflection
,”
Proceedings of the 27th Congress of the International Council of the Aeronautical Sciences, Nice, France, September 19–24
.
14.
Clayton
,
B. R.
, and
Filby
,
P.
,
1982
, “
Measured Effects of Oblique Flows and Change in Blade Pitch Angle on Performance and Wake Development of Model Wind Turbines
,”
Proceedings of the 4th BWEA Wind Energy Conference
,
13
, pp.
559
572
.
15.
Grant
,
I.
,
Parkin
,
P.
, and
Wang
,
X.
,
1997
, “
Optical Vortex Tracking Studies of a Horizontal Axis Wind Turbine in Yaw Using Laser-Sheet, Flow Visualisation
,”
Exp. Fluids
,
23
, pp.
513
519
.10.1007/s003480050142
16.
Manwell
,
J.
,
McGowan
,
J.
, and
Rogers
,
A.
,
2002
,
Wind Energy Explained: Theory Design and Application
,
John Wiley & Sons
,
New York
.
17.
Kochman
,
E.
,
2011
, “
Effect of Shear Profile and Yaw Angle on Wind Turbine Performance
,” ETH Zurich, Switzerland, LEC Internal Report.
You do not currently have access to this content.