The possibility to realize adaptive structures is of great interest in turbomachinery design, owing to the benefits related to enhanced performance and efficiency. To accomplish this, a challenging approach is the employment of shape memory alloys (SMAs), which can recover seemingly permanent strains by solid phase transformations whereby the so-called shape memory effect (SME) takes place. This paper presents the development of a heavy-duty automotive cooling axial fan with morphing blades activated by SMA strips that works as actuator elements in the polymeric blade structure. Concerning the fan performance, this new concept differs from a conventional viscous fan clutch solution especially during the nonstationary operating conditions. The blade design was performed in order to achieve the thermal activation of the strips by means of air stream flow. Two polymeric matrices were chosen to be tested in conjunction with a commercially available NiTi binary alloy, whose phase transformation temperatures (TTRs) were experimentally evaluated by imposing the actual operating thermal gradient. The SMA strips were then thermomechanically treated to memorize a bent shape and embedded in the polymeric blade. In a specifically designed wind tunnel, the different polymeric matrices equipped with the SMA strips were tested to assess the fluid temperature and surface pattern behavior of the blade. Upon heating, they tend to recover the memorized shape and the blade is forced to bend, leading to a camber variation and a trailing edge displacement. The recovery behavior of each composite structure (polymeric matrix with the SMA strips) was evaluated through digital image analysis techniques. The differences between the blade shape at the initial condition and at the maximum bending deformation were considered. According to these results, the best coupling of SMA strips and polymeric structure is assessed and its timewise behavior is compared to the traditional timewise behavior of a viscous fan clutch.

References

References
1.
Stoeckel
,
D.
,
1990
, “
Shape Memory Actuators for Automotive Applications
,”
Mater. Des.
,
11
(
6
), pp.
302
307
.
2.
Lin
,
W.
, and
Sunden
,
B.
,
2010
, “
Vehicle Cooling Systems for Reducing Fuel, Consumption and Carbon Dioxide: Literature Survey
,”
SAE
Technical Paper No. 2010-01-1509.
3.
Blair
,
E. C.
,
1974
, “
Comparison of Modulated (Viscous) Versus On-Off Fan Clutches
,”
SAE
Technical Paper No. 740596.
4.
Elmer
,
A.
,
Parry
,
S.
, and
Blandford
,
G.
,
1994
, “
Direct Sensing–Modulating Fan Clutch for Heavy Duty Commercial Vehicles
,”
SAE
Technical Paper No. 942254.
5.
Lee
,
K.
,
Lee
,
J.
, and
Koo
,
B.
,
1998
, “
Development of a Continuously Variable Speed Viscous Fan Clutch for Engine Cooling System
,”
SAE
Technical Paper No. 980838.
6.
Kim
,
K. B.
,
Choi
,
K. W.
,
Lee
,
K. H.
, and
Lee
,
K. S.
,
2010
, “
Active Coolant Control Strategies in Automotive Engines
,”
Int. J. Automot. Technol.
,
11
(
6
), pp.
767
772
.
7.
Sun
,
L.
,
Huang
,
W. M.
,
Ding
,
Z.
,
Zhao
,
Y.
,
Wang
,
C. C.
,
Purnawali
,
H.
, and
Tang
,
C.
,
2012
, “
Stimulus-Responsive Shape Memory Materials: A Review
,”
Mater. Des.
,
33
(
1
), pp.
577
640
.
8.
Hartl
,
D. J.
, and
Lagoudas
,
D. C.
,
2007
, “
Aerospace Applications of Shape Memory Alloys
,”
Proc. Inst. Mech. Eng., Part G: J. Aerosp. Eng.
, pp.
535
552
.
9.
Jani
,
J. M.
,
Leary
,
M.
,
Subic
,
A.
, and
Gibson
,
M. A.
,
2014
, “
A Review of Shape Memory Alloy Research, Applications and Opportunities
,”
Mater. Des.
,
56
(
4
), pp.
1078
1113
.
10.
Epps
,
J.
, and
Chopra
,
I.
,
2001
, “
In-Flight Tracking of Helicopter Rotor Blades Using Shape Memory Alloy Actuators
,”
Smart Mater. Struct.
,
10
(
1
), pp.
104
111
.
11.
Song
,
G.
, and
Ma
,
N.
,
2007
, “
Robust Control of a Shape Memory Alloy Wire Actuated Flap
,”
Smart Mater. Struct.
,
16
(
6
), pp.
N51
N57
.
12.
Jayasankar
,
S.
,
Senthilkumar
,
P.
,
Varughese
,
B.
,
Ramanaiah
,
B.
,
Viswanath
,
S.
,
Ramachandra
,
H. V.
, and
Dayananda
,
G. N.
,
2011
, “
Smart Aerodynamic Surface for a Typical Military Aircraft Using Shape Memory Elements
,”
J. Aircr.
,
48
(
5
), pp.
1968
1977
.
13.
Senthilkumar
,
P.
,
Jayasankar
,
S.
,
Satisha
,
Sateesh
,
V. L.
,
Kamaleshaiah
,
M. S.
, and
Dayananda
,
G. N.
,
2013
, “
Development and Wind Tunnel Evaluation of a Shape Memory Alloy Based Trim Tab Actuator for a Civil Aircraft
,”
Smart Mater. Struct.
,
22
(
9
), p.
095025
.
14.
Strelec
,
J. K.
,
Lagoudas
,
D. C.
,
Khan
,
M. A.
, and
Yen
,
J.
,
2003
, “
Design and Implementation of a Shape Memory Alloy Actuated Reconfigurable Airfoil
,”
J. Intell. Mater. Syst. Struct.
,
14
(
4–5
), pp.
257
273
.
15.
Barbarino
,
S.
,
Bilgen
,
O.
,
Ajaj
,
R. M.
,
Friswell
,
M. I.
, and
Inman
,
D. J.
,
2011
, “
A Review of Morphing Aircraft
,”
J. Intell. Mater. Syst. Struct.
,
22
(
9
), pp.
823
877
.
16.
Weisshaar
,
T. A.
,
2013
, “
Morphing Aircraft Systems: Historical Perspectives and Future Challenges
,”
J. Aircr.
,
50
(
2
), pp.
337
353
.
17.
Sofla
,
A. Y. N.
,
Meguid
,
S. A.
,
Tan
,
K. T.
, and
Yeo
,
W. K.
,
2010
, “
Shape Morphing of Aircraft Wing: Status and Challenges
,”
Mater. Des.
,
31
(
3
), pp.
1284
1292
.
18.
Oehler
,
S. D.
,
Hartl
,
D. J.
,
Lopez
,
R.
,
Malak
,
R. J.
, and
Lagoudas
,
D. C.
,
2012
, “
Design Optimization and Uncertainty Analysis of SMA Morphing Structures
,”
Smart Mater. Struct.
,
21
(
9
), p.
094016
.
19.
Kuder
, I
. K.
,
Arrieta
,
A. F.
,
Raither
,
W. E.
, and
Ermanni
,
P.
,
2013
, “
Variable Stiffness Material and Structural Concepts for Morphing Applications
,”
Prog. Aerosp. Sci.
,
63
(
11
), pp.
33
55
.
20.
Lachenal
,
X.
,
Daynes
,
S.
, and
Weaver
,
P. M.
,
2013
, “
Review of Morphing Concepts and Materials for Wind Turbine Blade Applications
,”
Wind Energy
,
16
(
2
), pp.
283
307
.
21.
Ponta
,
F. L.
,
Otero
,
A. D.
,
Rajana
,
A.
, and
Lagoa
,
L. I.
,
2014
, “
The Adaptive-Blade Concept in Wind-Power Applications
,”
Energy Sustainable Dev.
,
22
(
10
), pp.
3
12
.
22.
Nessim
,
W.
,
Zhang
,
F.
,
Changlu
,
Z.
, and
Zhenxia
,
Z.
,
2012
, “
A Simulation Study of an Advanced Thermal Management System for Heavy Duty Diesel Engines
,”
International Conference on Mechanical Engineering and Material Science
(
MEMS 2012
), Shanghai, Dec. 28–30, pp.
287
290
.
23.
Lagoudas
,
D. C.
,
2008
,
Shape Memory Alloys: Modeling and Engineering Applications
,
Springer
,
New York
.
24.
Rizzoni
,
R.
,
Merlin
,
M.
, and
Casari
,
D.
,
2013
, “
Shape Recovery Behaviour of Shape Memory Thin Strips in Cylindrical Bending: Experiments and Modelling
,”
Continuum Mech. Thermodyn.
,
25
(
2–4
), pp.
207
227
.
25.
Suman
,
A.
,
Fortini
,
A.
,
Aldi
,
N.
,
Merlin
,
M.
, and
Pinelli
,
M.
,
2015
, “
A Shape Memory Alloy-Based Morphing Axial Fan Blade—Part II: Blade Shape and CFD Analyses
,”
ASME
Paper No. GT2015-42700.
26.
Everett
,
G. B.
,
1974
, “
Comparison of Modulated (Viscous) Versus On-Off Fan Clutches
,”
SAE
Technical Paper No. 740596.
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