This paper presents the experimental results of the vertical axis wind turbine (VAWT), especially the Savonius rotors, which are developed for application on top of buildings due to lower wind speed compared with remote areas. The VAWT is regarded as the most suitable elegant candidate to be integrated with buildings for its relatively low operating noise, easy maintenance, and easy access. This study explored the interaction effect of the overlap ratio, phase-shift, and stage on the performance of the Savonius rotors in details. The results show that appropriate choice of the phase-shift angle according to the overlap ratio can not only increase the power coefficient of the Savonius rotors but also eliminate the negative static torque and smooth the variation of the static torque coefficient. Moreover, the performance of the two-stage rotors indicates that the two-stage rotor is the best candidate for this type of wind turbines or as a starting assistant for the Darrieus rotors.

References

References
1.
Altan
,
B. D.
,
Atilgan
,
M.
, and
Ozdamar
,
A.
, 2008, “
An Experimental Study on Improvement of a Savonius Rotor Performance With Curtaining
,”
Exp. Therm. Fluid Sci.
,
32
, pp.
1673
1678
.
2.
Shikha
,
Bhatti
,
T. S.
, and
Kothari
,
D. P.
, 2003, “
Vertical Axis Wind Rotor With Concentration by Convergent Nozzles
,”
Wind Eng.
,
27
(
6
), pp.
555
559
.
3.
Muller
,
G.
,
Jentsh
,
M. F.
, and
Stoddart
,
E.
, 2009, “
Vertical Axis Resistance Type Wind Turbines for Use in Buildings
,”
Renewable Energy
,
34
, pp.
1407
1412
.
4.
Mohamed
,
M. H.
,
Janiga
,
G.
,
Pap
,
E.
, and
Thévenin
,
D.
, 2010, “
Optimization of Savonius Turbines Using an Obstacle Shielding the Returning Blade
,”
Renewable Energy
,
35
(
11
), pp.
1
9
.
5.
Saha
,
U. K.
, and
Jaya Rajkumar
,
M.
, 2006, “
On the Performance Analysis of Savonius Rotor With Twisted Blades
,”
Renewable Energy
,
31
(
11
), pp.
1776
1788
.
6.
Kamoji
,
M. A.
,
Kedare
,
S. B.
, and
Prabhu
,
S. V.
, 2009, “
Performance Tests on Helical Savonius Rotors
,”
Renewable Energy
,
34
(
3
), pp.
521
529
.
7.
Kamoji
,
M. A.
,
Kedare
,
S. B.
, and
Prabhu
,
S. V.
, 2008, “
Experimental Investigations on the Single Stage, Two Stage and Three Stage Conventional Savonius Rotor
,”
Int. J. Energy Res.
,
32
(
10
), pp.
877
895
.
8.
Tsutomu
,
H.
,
Yan
,
L.
, and
Yutaka
,
H.
, 2005, “
Wind Tunnel Tests on a Different Phase Three Stage Savonius Rotor
,”
JSME Int. J., Ser. B
,
48
(
1
), pp.
9
16
.
9.
Menet
,
J.-L.
, 2004, “
A Double-Step Savonius Rotor for Local Production of Electricity—A Design Study
,”
Renewable Energy
,
29
(
11
), pp.
1843
1862
.
10.
Sheldahl
,
R. E.
,
Feltz
,
L. V.
, and
Blackwell
,
B. F.
, 1978, “
Wind Tunnel Performance Data for Two- and Three-Bucket Savonius Rotor
,”
J. Energy
,
2
, pp.
160
164
.
11.
Ushiyama
,
I.
, and
Nagai
,
H.
, 1988, “
Optimum Design Configurations and Performance of Savonius Rotors
,”
Wind Eng.
,
12
(
1
), pp.
59
75
.
12.
Barlow
,
J. B.
,
Rae
,
W. H.
, and
Pope
,
A.
, 1999,
Low Speed Wind Tunnel Testing
,
3rd Ed.
,
John Wiley & Sons, Inc.
,
New York
13.
Maskell
,
E. C.
, 1965, “
A Theory of the Blockage Effects on Bluff Bodies and Stalled Wings in a Closed Wind Tunnel
,” Technical Report No. 3400, Her Majesty’s Stationery Office, London.
14.
Alexander
,
A. J.
, 1978, “
Wind Tunnel Corrections for Savonius Rotors
,”
2nd International Symposium on Wind Energy Systems
, Amsterdam, Netherlands, pp.
E6
-69–E6-
80
.
15.
Alexander
,
A J.
,
, and
Holownia
,
B. P.
, 1978, “
Wind Tunnel Tests on a Savonius Rotor
,”
J. Wind Eng. Ind. Aerodyn.
,
3
(
4
), pp.
343
351
.
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