Unsteady conjugate natural convection in a semicircular cavity with a solid shell of finite thickness filled with a hybrid water-based suspension of Al2O3 and Cu nanoparticles (hybrid nanofluid) has been analyzed numerically. The governing equations for this investigation are formulated in terms of the dimensionless stream function, vorticity, and temperature and have been solved by the finite difference method of the second-order accuracy. The effects of the dimensionless time, Rayleigh number, thermal conductivity ratio, and the nanoparticles volume fraction on the flow patterns and heat transfer have been studied. The obtained results have revealed essential heat transfer enhancement at solid–fluid interface with addition of nanoparticles. In addition, a comparison of the heat transfer enhancement level due to the suspension of various nanoparticles materials (Al2O3 and Cu) in water as regular nanofluids (Al2O3/water and Cu/water) and as a hybrid Al2O3–Cu/water nanofluid is reported.

References

1.
Oosthuizen
,
P. H.
, and
Paul
,
J. T.
,
1985
, “
Free Convection Heat Transfer in a Cavity Fitted With a Horizontal Plate on the Cold Wall
,”
Advances in Enhanced Heat Transfer
, Vol.
43
,
S. M.
Shenkman
, ed.,
ASME
, New York, pp.
101
107
.
2.
Shakerin
,
S.
,
Bohn
,
M.
, and
Loehrke
,
R. I.
,
1988
, “
Natural Convection in an Enclosure With Discrete Roughness Elements on a Vertical Heated Wall
,”
Int. J. Heat Mass Transfer
,
31
(
7
), pp.
1423
1430
.
3.
Lee
,
J. H.
, and
Goldstein
,
R. J.
,
1988
, “
An Experimental Study on Natural Convection Heat Transfer in an Inclined Square Enclosure Containing Internal Energy Sources
,”
ASME J. Heat Transfer
,
110
(
2
), pp.
345
349
.
4.
Frederick
,
R. L.
,
1989
, “
Natural Convection in an Inclined Square Enclosure With a Partition Attached to Its Cold Wall
,”
Int. J. Heat Mass Transfer
,
32
(
1
), pp.
87
94
.
5.
Hasnaoui
,
M.
,
Vasseur
,
P.
, and
Bilgen
,
E.
,
1992
, “
Natural Convection in Rectangular Enclosures With Adiabatic Fins Attached on the Heated Wall
,”
Waerme Stoffuebertrag.
,
27
(
6
), pp.
357
368
.
6.
Facas
,
G. N.
,
1993
, “
Natural Convection in a Cavity With Fins Attached to Both Vertical Walls
,”
J. Thermophys. Heat Transfer
,
7
(
4
), pp.
555
560
.
7.
Nag
,
A.
,
Sarkar
,
A.
, and
Sastri
,
V. M. K.
,
1993
, “
Natural Convection in a Differentially Heated Square Cavity With a Horizontal Partition Plate on the Hot Wall
,”
Comput. Methods Appl. Mech. Eng.
,
110
(1–2), pp.
143
156
.
8.
Lakhal
,
E. K.
,
Hasnaoui
,
M.
,
Bilgen
,
E.
, and
Vasseur
,
P.
,
1997
, “
Natural Convection in Inclined Rectangular Enclosures With Perfectly Conducting Fins Attached on the Heated Wall
,”
Heat Mass Transfer
,
32
(
5
), pp.
365
373
.
9.
Bilgen
,
E.
,
2002
, “
Natural Convection in Enclosures With Partial Partitions
,”
Renewable Energy
,
26
(
2
), pp.
257
270
.
10.
Shi
,
X.
, and
Khodadadi
,
J. M.
,
2002
, “
Laminar Fluid Flow and Heat Transfer in a Lid Driven Cavity Due to a Thin Fin
,”
ASME J. Heat Transfer
,
124
(
6
), pp.
1056
1063
.
11.
Rahman
,
M.
, and
Sharif
,
M. A. R.
,
2003
, “
Numerical Study of Laminar Natural Convection in Inclined Rectangular Enclosures of Various Aspect Ratios
,”
Numer. Heat Transfer A
,
44
(
4
), pp.
355
373
.
12.
Shi
,
X.
, and
Khodadadi
,
J. M.
,
2003
, “
Laminar Natural Convection Heat Transfer in a Differentially Heated Square Cavity Due to a Thin Fin on the Hot Wall
,”
ASME J. Heat Transfer
,
125
(
4
), pp.
624
634
.
13.
Bilgen
,
E.
,
2005
, “
Natural Convection in Cavities With a Thin Fin on the Hot Wall
,”
Int. J. Heat Mass Transfer
,
48
(
17
), pp.
3493
3505
.
14.
Gdalevich
,
L. B.
, and
Fertman
,
V. E.
,
1977
, “
Conjugate Problems of Natural Convection
,”
J. Eng. Phy.
,
33
(3), pp. 1120–1126.
15.
Frederick
,
R. L.
, and
Valencia
,
A.
,
1989
, “
Heat Transfer in a Square Cavity With a Conducting Partition on Its Hot Wall
,”
Int. Commun. Heat Mass Transfer
,
16
(
3
), pp.
347
354
.
16.
Scozia
,
R.
, and
Frederick
,
R. L.
,
1991
, “
Natural Convection in Slender Cavities With Multiple Fins Attached on an Active Wall
,”
Numer. Heat Transfer A
,
20
(
2
), pp.
127
158
.
17.
Acharya
,
S.
, and
Tsang
,
C. H.
,
1987
, “
Influence of Wall Conduction on Natural Convection in an Inclined Square Enclosure
,”
Waerme Stoffuebertrag.
,
21
(1), pp.
19
30
.
18.
Liaqat
,
A.
, and
Baytas
,
A. C.
,
2001
, “
Numerical Comparison of Conjugate and Non-Conjugate Natural Convection for Internally Heated Semi-Circular Pools
,”
Int. J. Heat Fluid Flow
,
22
(
6
), pp.
650
656
.
19.
Ben-Nakhi
,
A.
, and
Chamkha
,
A. J.
,
2007
, “
Conjugate Natural Convection in a Square Enclosure With Inclined Thin Fin of Arbitrary Length
,”
Int. J. Therm. Sci.
,
46
(
5
), pp.
467
478
.
20.
Saeid
,
N. H.
,
2007
, “
Conjugate Natural Convection in a Porous Enclosure: Effect of Conduction in One of the Vertical Walls
,”
Int. J. Therm. Sci.
,
46
(
6
), pp.
531
539
.
21.
Varol
,
Y.
,
Oztop
,
H. F.
, and
Pop
,
I.
,
2009
, “
Conjugate Heat Transfer in Porous Triangular Enclosures With Thick Bottom Wall
,”
Int. J. Numer. Method Heat Fluid Flow
,
19
(
5
), pp.
650
664
.
22.
Chamkha
,
A. J.
, and
Ismael
,
M. A.
,
2013
, “
Conjugate Heat Transfer in a Porous Cavity Heated by a Triangular Thick Wall
,”
Numer. Heat Transfer A
,
63
(
2
), pp.
144
158
.
23.
Martyushev
,
S. G.
, and
Sheremet
,
M. A.
,
2014
, “
Conjugate Natural Convection Combined With Surface Thermal Radiation in an Air Filled Cavity With Internal Heat Source
,”
Int. J. Therm. Sci.
,
76
, pp.
51
67
.
24.
Martyushev
,
S. G.
, and
Sheremet
,
M. A.
,
2014
, “
Conjugate Natural Convection Combined With Surface Thermal Radiation in a Three-Dimensional Enclosure With a Heat Source
,”
Int. J. Heat Mass Transfer
,
73
, pp.
340
353
.
25.
Das
,
S. K.
,
Choi
,
S. U. S.
,
Yu
,
W.
, and
Pradeep
,
T.
,
2007
,
Nanofluids-Science and Technology
,
Wiley
,
Hoboken, NJ
.
26.
Buongiorno
,
J.
,
2006
, “
Convective Transport in Nanofluids
,”
ASME J. Heat Transfer
,
128
(
3
), pp.
240
250
.
27.
Kuznetsov
,
G. V.
, and
Sheremet
,
M. A.
,
2011
, “
Unsteady Natural Convection of Nanofluids in an Enclosure Having Finite Thickness Walls
,”
Comput. Therm. Sci.
,
3
(
5
), pp.
427
443
.
28.
Chamkha
,
A. J.
, and
Ismael
,
M. A.
,
2013
, “
Conjugate Heat Transfer in a Porous Cavity Filled With Nanofluids and Heated by a Triangular Thick Wall
,”
Int. J. Therm. Sci.
,
67
, pp.
135
151
.
29.
Sheremet
,
M. A.
, and
Pop
,
I.
,
2014
, “
Conjugate Natural Convection in a Square Porous Cavity Filled by a Nanofluid Using Buongiorno's Mathematical Model
,”
Int. J. Heat Mass Transfer
,
79
, pp.
137
145
.
30.
Ismael
,
M. A.
, and
Chamkha
,
A. J.
,
2015
, “
Conjugate Natural Convection in a Differentially Heated Composite Enclosure Filled With a Nanofluid
,”
J. Porous Media
,
18
(
7
), pp.
699
716
.
31.
Ismael
,
M. A.
,
Armaghani
,
T.
, and
Chamkha
,
A. J.
,
2016
, “
Conjugate Heat Transfer and Entropy Generation in a Cavity Filled With a Nanofluid-Saturated Porous Media and Heated by a Triangular Solid
,”
J. Taiwan Inst. Chem. Eng.
,
59
, pp.
138
151
.
32.
Noghrehabadi
,
A.
,
Pourrajab
,
R.
, and
Ghalambaz
,
M.
,
2012
, “
Effect of Partial Slip Boundary Condition on the Flow and Heat Transfer of Nanofluids Past Stretching Sheet Prescribed Constant Wall Temperature
,”
Int. J. Therm. Sci.
,
54
, pp.
253
261
.
33.
Noghrehabadi
,
A.
,
Ghalambaz
,
M.
,
Ghalambaz
,
M.
, and
Ghanbarzadeh
,
A.
,
2012
, “
Comparing Thermal Enhancement of Ag-Water and SiO2-Water Nanofluids Over an Isothermal Stretching Sheet With Suction or Injection
,”
J. Comput. Appl. Res. Mech. Eng.
,
2
(1), pp.
37
49
.
34.
Noghrehabadi
,
A.
,
Saffarian
,
M. R.
,
Pourrajab
,
R.
, and
Ghalambaz
,
M.
,
2013
, “
Entropy Analysis for Nanofluid Flow Over a Stretching Sheet in the Presence of Heat Generation/Absorption and Partial Slip
,”
J. Mech. Sci. Technol.
,
27
(
3
), pp.
927
937
.
35.
Zaraki
,
A.
,
Ghalambaz
,
M.
,
Chamkha
,
A. J.
,
Ghalambaz
,
M.
, and
De Rossi
,
D.
,
2015
, “
Theoretical Analysis of Natural Convection Boundary Layer Heat and Mass Transfer of Nanofluids: Effects of Size, Shape and Type of Nanoparticles, Type of Base Fluid and Working Temperature
,”
Adv. Powder Technol.
,
26
(
3
), pp.
935
946
.
36.
Pop
,
I.
,
Ghalambaz
,
M.
, and
Sheremet
,
M.
,
2016
, “
Free Convection in a Square Porous Cavity Filled With a Nanofluid Using Thermal Non Equilibrium and Buongiorno Models
,”
Int. J. Numer. Methods Heat Fluid Flow
,
26
(3–4), pp.
671
693
.
37.
Li
,
H.
,
Ha
,
C. S.
, and
Kim
,
I.
,
2009
, “
Fabrication of Carbon Nanotube/SiO2 and Carbon Nanotube/SiO2/Ag Nanoparticles Hybrids by Using Plasma Treatment
,”
Nanoscale Res. Lett.
,
4
(
11
), pp.
1384
1388
.
38.
Guo
,
S.
,
Dong
,
S.
, and
Wang
,
E.
,
2008
, “
Gold/Platinum Hybrid Nanoparticles Supported on Multi Walled Carbon Nanotube/Silica Coaxial Nanocables: Preparation and Application as Electrocatalysts for Oxygen Reduction
,”
J. Phys. Chem. C
,
112
(
7
), pp.
2389
2393
.
39.
Sarkar
,
J.
,
Ghosh
,
P.
, and
Adil
,
A.
,
2015
, “
A Review on Hybrid Nanofluids: Recent Research, Development and Applications
,”
Renewable Sustainable Energy Rev.
,
43
, pp.
164
177
.
40.
Suresh
,
S.
,
Venkitaraj
,
K. P.
,
Selvakumar
,
P.
, and
Chandrasekar
,
M.
,
2011
, “
Synthesis of Al2O3–Cu/Water Hybrid Nanofluids Using Two Step Method and Its Thermo Physical Properties
,”
Colloids Surf., A
,
388
(1–3), pp.
41
48
.
41.
Ho
,
C. J.
,
Huang
,
J. B.
,
Tsai
,
P. S.
, and
Yang
,
Y. M.
,
2011
, “
On Laminar Convective Cooling Performance of Hybrid Water-Based Suspensions of Al2O3 Nanoparticles and MEPCM Particles in a Circular Tube
,”
Int. J. Heat Mass Transfer
,
54
(11–12), pp.
2397
2407
.
42.
Ho
,
C. J.
,
Huang
,
J. B.
,
Tsai
,
P. S.
, and
Yang
,
Y. M.
,
2011
, “
Water-Based Suspensions of Al2O3 Nanoparticles and MEPCM Particles on Convection Effectiveness in a Circular Tube
,”
Int. J. Therm. Sci.
,
50
(
5
), pp.
736
748
.
43.
Takabi
,
B.
, and
Shokouhmand
,
H.
,
2015
, “
Effects of Al2O3–Cu/Water Hybrid Nanofluid on Heat Transfer and Flow Characteristics in Turbulent Regime
,”
Int. J. Mod. Phys. C
,
26
(
04
), p.
1550047
.
44.
Sheremet
,
M. A.
,
Grosan
,
T.
, and
Pop
,
I.
,
2015
, “
Free Convection in a Square Cavity Filled With a Porous Medium Saturated by Nanofluid Using Tiwari and Das' Nanofluid Model
,”
Transp. Porous Media
,
106
(
3
), pp.
595
610
.
45.
Cho
,
C. C.
,
Chiu
,
C. H.
, and
Lai
,
C. Y.
,
2016
, “
Natural Convection and Entropy Generation of Al2O3–Water Nanofluid in an Inclined Wavy-Wall Cavity
,”
Int. J. Heat Mass Transfer
,
97
, pp.
511
520
.
46.
Sheremet
,
M. A.
,
2012
, “
Interaction of Two-Dimensional Thermal “Plumes” From Local Sources of Energy Under Conditions of Conjugate Natural Convection in a Horizontal Cylinder
,”
J. Appl. Mech. Tech. Phys.
,
53
(
4
), pp.
566
576
.
47.
Sheremet
,
M. A.
, and
Pop
,
I.
,
2014
, “
Thermo-Bioconvection in a Square Porous Cavity Filled by Oxytactic Microorganisms
,”
Transp. Porous Media
,
103
(
2
), pp.
191
205
.
48.
Shi
,
Y.
,
Zhao
,
T. S.
, and
Guo
,
Z. L.
,
2006
, “
Finite Difference-Based Lattice Boltzmann Simulation of Natural Convection Heat Transfer in a Horizontal Concentric Annulus
,”
Comput. Fluids
,
35
(
1
), pp.
1
15
.
49.
Kuehn
,
T. H.
, and
Goldstein
,
R. J.
,
1978
, “
An Experimental Study of Natural Convection Heat Transfer in Concentric and Eccentric Horizontal Cylindrical Annuli
,”
ASME J. Heat Transfer
,
100
(
4
), pp.
635
640
.
50.
Shahraki
,
F.
,
2002
, “
Modeling of Buoyancy-Driven Flow and Heat Transfer for Air in a Horizontal Annulus: Effects of Vertical Eccentricity and Temperature-Dependent Properties
,”
Numer. Heat Transfer, Part A
,
42
(
6
), pp.
603
621
.
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