Cross-flow or vertical-axis turbines are flow energy conversion devices in which lift forces cause blades to rotate around an axis perpendicular to the flow. In marine currents, rivers, and some wind energy applications, cross-flow turbines are a promising alternative to more conventional axial-flow turbines. The performance implications of the choice of structure used to mount turbine blades to the central shaft are examined experimentally in a recirculating water flume. Turbine performance is found to be strongly dependent on the choice of the mounting structure. Power loss due to rotational drag on these structures is estimated experimentally by rotating the mounting structure without blades. Through a perturbation-theory approach, interactions between turbine blades and mounting structures are examined. Analytical models for the power loss due to mounting structure drag are introduced and shown to be consistent with experiments. To provide guidance for cross-flow turbine design, the models are re-formulated in terms of non-dimensional turbine geometric and operational parameters. Mounting blades solely at their mid-span is shown to decrease performance through multiple fluid effects. Using foil cross-section struts located at the turbine blade tips is found to result in the highest turbine performance.

1.
F.
Balduzzi
,
A.
Bianchini
,
E. A.
Carnevale
,
L.
Ferrari
, and
S.
Magnani
, “
Feasibility analysis of a Darrieus vertical-axis wind turbine installation in the rooftop of a building
,”
Appl. Energy
97
,
921
929
(
2012
).
2.
H. J.
Sutherland
,
D. E.
Berg
, and
T. D.
Ashwill
, “
A retrospective of VAWT technology,” Sandia Report No. SAND2012-0304
,
2012
.
3.
B.
Strom
,
S. L.
Brunton
, and
B. L.
Polagye
, “
Intracycle angular velocity control of cross-flow turbines
,”
Nat. Energy
2
,
17103
(
2017
).
4.
J. O.
Dabiri
, “
Potential order-of-magnitude enhancement of wind farm power density via counter-rotating vertical-axis wind turbine arrays
,”
J. Renewable Sustainable Energy
3
,
043104
(
2011
).
5.
J.
Abraham
,
B.
Plourde
,
G.
Mowry
,
W.
Minkowycz
, and
E.
Sparrow
, “
Summary of savonius wind turbine development and future applications for small-scale power generation
,”
J. Renewable Sustainable Energy
4
,
042703
(
2012
).
6.
B.
Plourde
,
J.
Abraham
,
G.
Mowry
, and
W.
Minkowycz
, “
An experimental investigation of a large, vertical-axis wind turbine: Effects of venting and capping
,”
Wind Eng.
35
,
213
222
(
2011
).
7.
S.
Salter
, “
Are nearly all tidal stream turbine designs wrong?
,” in
4th International Conference on Ocean Energy
(
2012
).
8.
A.
Copping
,
N.
Sather
,
L.
Hanna
,
J.
Whiting
,
G.
Zydlewski
,
G.
Staines
,
A.
Gill
,
I.
Hutchison
,
A.
OâHagan
,
T.
Simas
 et al, “
Annex iv 2016 state of the science report: Environmental effects of marine renewable energy development around the world
,” Ocean Energy Systems,
2016
.
9.
T. J.
Carrigan
,
B. H.
Dennis
,
Z. X.
Han
, and
B. P.
Wang
, “
Aerodynamic shape optimization of a vertical-axis wind turbine using differential evolution
,”
ISRN Renewable Energy
2012
,
528418
.
10.
M. R.
Castelli
and
E.
Benini
, “
Effect of blade inclination angle on a darrieus wind turbine
,”
J. Turbomachinery
134
,
031016
(
2012
).
11.
C.-C.
Chen
and
C.-H.
Kuo
, “
Effects of pitch angle and blade camber on flow characteristics and performance of small-size darrieus vawt
,”
J. Visualization
16
,
65
74
(
2013
).
12.
C.
Consul
,
R.
Willden
,
E.
Ferrer
, and
M.
McCulloch
, “
Influence of solidity on the performance of a cross-flow turbine
,” in
8th European Wave and Tidal Energy Conference,
Uppsala, Sweden (
2009
).
13.
R.
Gosselin
,
G.
Dumas
, and
M.
Boudreau
, “
Parametric study of h-darrieus vertical-axis turbines using urans simulations
,”
21st Annual Conference of the CFD Society of Canada
(
2013
).
14.
L. A.
Danao
,
J.
Edwards
,
O.
Eboibi
, and
R.
Howell
, “
A numerical investigation into the effects of fluctuating wind on the performance of a small scale vertical axis wind turbine
,”
Eng. Lett.
21
,
149
157
(
2013
).
15.
D.
Malcolm
, “
Dynamic response of a darrieus rotor wind turbine subject to turbulent flow
,”
Eng. Struct.
10
,
125
134
(
1988
).
16.
P.
Bachant
,
M.
Wosnik
,
B.
Gunawan
, and
V. S.
Neary
, “
Experimental study of a reference model vertical-axis cross-flow turbine
,”
PloS one
11
,
e0163799
(
2016
).
17.
L.
Battisti
,
L.
Zanne
,
S.
DellâAnna
,
V.
Dossena
,
G.
Persico
, and
B.
Paradiso
, “
Aerodynamic measurements on a vertical axis wind turbine in a large scale wind tunnel
,”
J. Energy Resources Technol.
133
,
031201
(
2011
).
18.
M.
Kinzel
,
Q.
Mulligan
, and
J. O.
Dabiri
, “
Energy exchange in an array of vertical-axis wind turbines
,”
J. Turbul.
13
,
1
13
(
2012
).
19.
E.
Reid
, “
The effects of shielding the tips of airfoils
,”
NACA Report No. 201, National Advisory Committee for Aeronautics
, Hampton, VA,
1924
.
20.
I.
Kroo
, “
Drag due to lift: Concepts for prediction and reduction
,”
Annu. Rev. Fluid Mech.
33
,
587
617
(
2001
).
21.
A.
Gorlov
, “
Development of the helical reaction hydraulic turbine. Final technical report, July 1, 1996–June 30, 1998,” Technical Report No. DE-FGO1-96EE 15669
, US Department of Energy, EE-20, Washington, DC (United States),
1998
.
22.
M.
Khan
,
G.
Bhuyan
,
M.
Iqbal
, and
J.
Quaicoe
, “
Hydrokinetic energy conversion systems and assessment of horizontal and vertical axis turbines for river and tidal applications: A technology status review
,”
Appl. Energy
86
,
1823
1835
(
2009
).
23.
M.
Shiono
,
K.
Suzuki
, and
S.
Kiho
, “
An experimental study of the characteristics of a darrieus turbine for tidal power generation
,”
Electr. Eng. Jpn.
132
,
38
47
(
2000
).
24.
P.
Bachant
and
M.
Wosnik
, “
Performance measurements of cylindrical-and spherical-helical cross-flow marine hydrokinetic turbines, with estimates of exergy efficiency
,”
Renewable Energy
74
,
318
325
(
2015
).
25.
P.
Bachant
and
M.
Wosnik
, “
Characterising the near-wake of a cross-flow turbine
,”
J. Turbul.
16
,
392
410
(
2015
).
26.
C.
Hill
,
V. S.
Neary
,
B.
Gunawan
,
M.
Guala
, and
F.
Sotiropoulos
,
US Department of Energy Reference Model Program rm2: Experimental Results
(
Sandia National Laboratories
,
Albuquerque, NM
,
2014
).
27.
A.
Goude
,
S.
Lundin
, and
M.
Leijon
, “
A parameter study of the influence of struts on the performance of a vertical-axis marine current turbine
,” in
Proceedings of the 8th European Wave and Tidal Energy Conference, EWTEC09, Uppsala, Sweden
(Citeseer,
2009
), pp.
477
483
.
28.
R.
Gosselin
,
G.
Dumas
, and
M.
Boudreau
, “
Parametric study of h-darrieus vertical-axis turbines using cfd simulations
,”
J. Renewable Sustainable Energy
8
,
053301
(
2016
).
29.
G.
Rawlings
,
M.
Alidadi
,
V.
Klaptocz
,
Y.
Nabavi
,
Y.
Li
,
J.
Mikkelsen
,
S.
Calisal
 et al, “
Application of end plates for vertical axis hydro turbine performance enhancement
,” in
The Eighteenth International Offshore and Polar Engineering Conference
(International Society of Offshore and Polar Engineers,
2008
).
30.
Y.
Li
and
S. M.
Calisal
, “
Three-dimensional effects and arm effects on modeling a vertical axis tidal current turbine
,”
Renewable Energy
35
,
2325
2334
(
2010
).
31.
B.
Strom
,
S. L.
Brunton
, and
B.
Polagye
, “
Consequences of preset pitch angle on cross-flow turbine hydrodynamics
,” in
Proceeding of the European Wave and Tidal Energy Conference
(
2015
).
32.
W.
McCroskey
, “
The phenomenon of dynamic stall
,” Technical Memorandum No. 81264, National Aeronautics and Space Administration Moffett Field CA, AMES Research Center,
1981
.
33.
J.
Wu
,
A.
Vakili
, and
J.
Wu
, “
Review of the physics of enhancing vortex lift by unsteady excitation
,”
Prog. Aerosp. Sci.
28
,
73
131
(
1991
).
34.
G.
Schewe
, “
Reynolds-number-effects in flow around a rectangular cylinder with aspect ratio 1: 5
,”
J. Fluids Struct.
39
,
15
26
(
2013
).
35.
A.
Šoda
,
C.
Mannini
, and
M.
Sjerić
, “
Investigation of unsteady air flow around two-dimensional rectangular cylinders
,”
Trans. FAMENA
35
,
11
(
2011
).
36.
M.
Drela
, “
Xfoil: an analysis and design system for low Reynolds number airfoils
,” in
Low Reynolds Number Aerodynamics
(
Springer
,
1989
), pp.
1
12
.
37.
H. J.
Goett
and
W. K.
Bullivant
, “
Tests of NACA 0009, 0012, and 0018 airfoils in the full-scale tunnel
,”
Technical Report No. 647
, National Advisory Committee for Aeronautics,
1939
.
38.
E. N.
Jacobs
and
A.
Sherman
, “
Airfoil section characteristics as affected by variations of the Reynolds number
,”
Technical Report No. 586
, National Advisory Committee for Aeronautics,
1937
.
39.
A. E.
Von Doenhoff
and
F. T.
Abbott
, “
The Langley two-dimensional low-turbulence pressure tunnel
,”
Technical Note No. 1283
, National Advisory Committee for Aeronautics,
1947
.
40.
L. K.
Loftin
, Jr.
and
H. A.
Smith
, “
Aerodynamic characteristics of 15 naca airfoil sections at seven Reynolds numbers from 0.7 × 106 to 9.0 × 106
,”
Technical Note No. 1945
, National Advisory Committee for Aeronautic,
1949
.
41.
I. H.
Abbott
and
A. E.
Von Doenhoff
,
Theory of Wing Sections, Including a Summary of Airfoil Data
(
Courier Corporation
,
1959
).
42.
R. E.
Sheldahl
and
P. C.
Klimas
, “
Aerodynamic characteristics of seven symmetrical airfoil sections through 180-degree angle of attack for use in aerodynamic analysis of vertical axis wind turbines
,”
Technical Report No. SAND80-2114
, Sandia National Labs., Albuquerque, NM (USA),
1981
.
43.
C. L.
Ladson
, “
Effects of independent variation of mach and Reynolds numbers on the low-speed aerodynamic characteristics of the naca 0012 airfoil section
,”
NASA Technical Memorandum No. 4074
, National Aeronautics and Space Administration,
1988
.
44.
E.
Laitone
, “
Wind tunnel tests of wings at Reynolds numbers below 70 000
,”
Exp. Fluids
23
,
405
409
(
1997
).
45.
T.
Ohtake
,
Y.
Nakae
, and
T.
Motohashi
, “
Nonlinearity of the aerodynamic characteristics of naca0012 aerofoil at low Reynolds numbers
,”
Jpn. Soc. Aeronaut. Space Sci.
55
,
439
445
(
2007
).
46.
T.
Von Kármán
, “
Über laminare und turbulente reibung
,”
ZAMM-J. Appl. Math. Mech./Z. Angew. Math. Mech.
1
,
233
252
(
1921
).
47.
E.
Sparrow
and
J.
Gregg
, “
Mass transfer, flow, and heat transfer about a rotating disk
,”
J. Heat Transfer
82
,
294
302
(
1960
).
48.
N.
Rott
and
W. S.
Lewellen
, “
Boundary layers due to the combined effects of rotation and translation
,”
Phys. Fluids
10
,
1867
1873
(
1967
).
49.
H.
Schlichting
,
Boundary-Layer Theory
, 7th ed. (
McGraw-Hill
,
1979
).
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