Abstract

A computational work is performed on laminar free convection from an isothermally heated spherical shaped open cavity with negligible wall thickness suspended in the air. Fluid flow and heat transfer are analyzed in detail by solving governing differential equations (continuity, momentum, and energy) numerically over wide ranges of the relevant dimensionless parameters, namely, Rayleigh number, 104 ≤ Ra ≤ 108; and height to diameter ratio, 0.15 ≤ h/D ≤0.95. The detailed behavior of thermal and flow fields is delineated by suitable visualization techniques for different Ra and h/D. The influence of Ra and h/D on the local and average Nusselt number is also predicted and it is observed that the average Nusselt number on both outer and inner surfaces decreases with the increase of h/D for a constant value of Ra. A suitable correlation for the net average Nusselt number is obtained for the spherical-shaped open vessel surface as a function of Ra, and h/D based on the computed data points, which is expected to be relevant for various academic and industrial operations. This study can be helpful in various industrial operations, such as heat treatment of foodstuffs, shield surfaces, thermal insulations, melting of polymer pellets, and fluidized reactors.

References

1.
Hassan
,
K. E.
, and
Mohamed
,
S. A.
,
1970
, “
Natural Convection From Isothermal Flat Surfaces
,”
Int. J. Heat Mass Transfer
,
13
(
12
), pp.
1873
1886
.10.1016/0017-9310(70)90090-6
2.
Schaub
,
M.
,
Kriegel
,
M.
, and
Brandt
,
S.
,
2019
, “
Analytical Prediction of Heat Transfer by Unsteady Natural Convection at Vertical Flat Plates in Air
,”
Int. J. Heat Mass Transfer
,
144
, p.
118665
.10.1016/j.ijheatmasstransfer.2019.118665
3.
Roy
,
S.
, and
Anilkumar
,
D.
,
2006
, “
Unsteady Mixed Convection From a Moving Vertical Slender Cylinder
,”
ASME J. Heat Transfer-Trans. ASME
,
128
(
4
), pp.
368
373
.10.1115/1.2165206
4.
Heckel
,
J. J.
,
Chen
,
T. S.
, and
Armaly
,
B. F.
,
1989
, “
Mixed Convection Along Slender Vertical Cylinders With Variable Surface Temperature
,”
Int. J. Heat Mass Transfer
,
32
(
8
), pp.
1431
1442
.10.1016/0017-9310(89)90067-7
5.
Kang
,
G. U.
, and
Yook
,
D. S.
,
2019
, “
Laminar Natural Convection Heat Transfer Depending on Diameters of Vertical Cylinders With Circular Cross-Section With High Prandtl Number
,”
Int. J. Heat Mass Transfer
,
134
, pp.
554
565
.10.1016/j.ijheatmasstransfer.2019.01.073
6.
Acharya
,
S.
,
Agrawal
,
S.
, and
Dash
,
S. K.
,
2018
, “
Numerical Analysis of Natural Convection Heat Transfer From a Vertical Hollow Cylinder Suspended in Air
,”
ASME J. Heat Transfer-Trans. ASME
,
140
(
5
), p. 0
52501
.10.1115/1.4038478
7.
Rana
,
B. K.
,
Singh
,
B.
, and
Senapati
,
J. R.
,
2021
, “
Thermofluid Characteristics on Natural and Mixed Convection Heat Transfer From a Vertical Rotating Hollow Cylinder Immersed in Air: A Numerical Exercise
,”
ASME J. Heat Transfer-Trans. ASME
,
143
(
2
), p. 0
22601
.10.1115/1.4048830
8.
Rana
,
B. K.
, and
Senapati
,
J. R.
,
2021
, “
Entropy Generation Analysis and Cooling Time Estimation for a Rotating Vertical Hollow Tube in the Air Medium
,”
ASME J. Heat Transfer-Trans. ASME
,
143
(
4
), p. 0
42101
.10.1115/1.4049839
9.
Rana
,
B. K.
,
2022
, “
Conjugate Steady Natural Convection Analysis Around Thick Tapered Vertical Pipe Suspended in the Air
,”
Sādhanā
,
47
(
1
), pp.
1
16
.10.1007/s12046-021-01780-4
10.
Jia
,
H.
, and
Gogos
,
G.
,
1996
, “
Laminar Natural Convection Heat Transfer From Isothermal Spheres
,”
Int. J. Heat Mass Transfer
,
39
(
8
), pp.
1603
1615
.10.1016/0017-9310(95)00259-6
11.
Potter
,
J. M.
, and
Riley
,
N.
,
1980
, “
Free Convection From a Heated Sphere at Large Grashof Number
,”
J. Fluid Mech.
,
100
(
4
), pp.
769
783
.10.1017/S0022112080001395
12.
Singh
,
S. N.
, and
Hasan
,
M. M.
,
1983
, “
Free Convection About a Sphere at Small Grashof Number
,”
Int. J. Heat Mass Transfer
,
26
(
5
), pp.
781
783
.10.1016/0017-9310(83)90028-5
13.
Prhashanna
,
A.
, and
Chhabra
,
R. P.
,
2010
, “
Free Convection in Power-Law Fluids From a Heated Sphere
,”
Chem. Eng. Sci
,.,
65
(
23
), pp.
6190
6205
.10.1016/j.ces.2010.09.003
14.
Bruneau
,
C. H.
,
Fischer
,
P.
,
Xiong
,
Y. L.
, and
Kellay
,
H.
,
Cyclobulle Collaboration
2018
, “
Numerical Simulations of Thermal Convection on a Hemisphere
,”
Phys. Rev. Fluids
,
3
(
4
), p.
043502
.10.1103/PhysRevFluids.3.043502
15.
Liu
,
J.
,
Zhao
,
C. J.
,
Liu
,
H.
, and
Lu
,
W. Q.
,
2018
, “
Numerical Study of Laminar Natural Convection Heat Transfer From a Hemisphere With Adiabatic Plane and Isothermal Hemispherical Surface
,”
Int. J. Therm. Sci.
,
131
, pp.
132
143
.10.1016/j.ijthermalsci.2018.05.013
16.
Zhang
,
J.
,
Liu
,
J.
, and
Lu
,
W.
,
2019
, “
Study on Laminar Natural Convection Heat Transfer From a Hemisphere With Uniform Heat Flux Surface
,”
J. Therm. Sci.
,
28
(
2
), pp.
232
245
.10.1007/s11630-018-1051-y
17.
Behera
,
S.
,
Acharya
,
S.
, and
Dash
,
S. K.
,
2020
, “
Natural Convection Heat Transfer From Linearly, Circularly and Parabolically Bent Plates: A Study of Shape Effect
,”
Int. J. Therm. Sci.
,
150
, p.
106219
.10.1016/j.ijthermalsci.2019.106219
18.
Nasr
,
K. B.
,
Chouikh
,
R.
,
Kerkeni
,
C.
, and
Guizani
,
A.
,
2006
, “
Numerical Study of the Natural Convection in Cavity Heated From the Lower Corner and Cooled From the Ceiling
,”
Appl. Therm. Eng.
,
26
(
7
), pp.
772
775
.10.1016/j.applthermaleng.2005.09.011
19.
Johnson
,
C. E.
,
1986
, “
Evaluation of Correlations for Natural Convection Cooling of Electronic Equipment
,”
Heat Transfer Eng.
,
7
(
1–2
), pp.
36
45
.10.1080/01457638608939643
20.
Yeh
,
L. T.
,
1995
, “
Review of Heat Transfer Technologies in Electronic Equipment
,”
ASME J. Electron. Packag
,
117
(
4
), pp.
333
339
.10.1115/1.2792113
21.
Incropera
,
F. P.
,
1988
, “
Convection Heat Transfer in Electronic Equipment Cooling
,”
ASME J. Heat Transfer-Trans. ASME
,
110
(
4b
), pp.
1097
1111
.10.1115/1.3250613
22.
Baïri
,
A.
,
De María
,
J. G.
,
Baïri
,
I.
,
Laraqi
,
N.
,
Zarco-Pernia
,
E.
, and
Alilat
,
N.
,
2012
, “
2D Transient Natural Convection in Diode Cavities Containing an Electronic Equipment With Discrete Active Bands Under Constant Heat Flux
,”
Int. J. Heat Mass Transfer
,
55
(
19–20
), pp.
4970
4980
.10.1016/j.ijheatmasstransfer.2012.04.032
23.
Xin
,
R. C.
, and
Ebadian
,
M. A.
,
1996
, “
Natural Convection Heat Transfer From Helicoidal Pipes
,”
J. Thermophys. Heat Transfer
,
10
(
2
), pp.
297
302
.10.2514/3.787
24.
Garoosi
,
F.
,
Hoseininejad
,
F.
, and
Rashidi
,
M. M.
,
2016
, “
Numerical Study of Natural Convection Heat Transfer in a Heat Exchanger Filled With Nanofluids
,”
Energy
,
109
, pp.
664
678
.10.1016/j.energy.2016.05.051
25.
Spitler
,
J. D.
,
Javed
,
S.
, and
Ramstad
,
R. K.
,
2016
, “
Natural Convection in Groundwater-Filled Boreholes Used as Ground Heat Exchangers
,”
Appl. Energy
,
164
, pp.
352
365
.10.1016/j.apenergy.2015.11.041
26.
Dimmick
,
G. R.
,
Chatoorgoon
,
V.
,
Khartabil
,
H. F.
, and
Duffey
,
R. B.
,
2002
, “
Natural-Convection Studies for Advanced CANDU Reactor Concepts
,”
Nucl. Eng. Des.
,
215
(
1–2
), pp.
27
38
.10.1016/S0029-5493(02)00039-0
27.
Liu
,
L.
,
Deng
,
J.
,
Zhang
,
D.
,
Wang
,
C.
,
Qiu
,
S.
, and
Su
,
G. H.
,
2020
, “
Experimental Analysis of Flow and Convective Heat Transfer in the Water-Cooled Packed Pebble Bed Nuclear Reactor Core
,”
Prog. Nucl. Energy
,
122
, p.
103298
.10.1016/j.pnucene.2020.103298
28.
Wu
,
S. Y.
,
Xiao
,
L.
, and
Li
,
Y. R.
,
2011
, “
Effect of Aperture Position and Size on Natural Convection Heat Loss of a Solar Heat-Pipe Receiver
,”
Appl. Therm. Eng.
,
31
(
14–15
), pp.
2787
2796
.10.1016/j.applthermaleng.2011.05.004
29.
Manzoor
,
M. T.
,
Lenci
,
G.
, and
Tetreault-Friend
,
M.
,
2021
, “
Convection in Volumetrically Absorbing Solar Thermal Receivers: A Theoretical Study
,”
Sol. Energy
,
224
, pp.
1358
1368
.10.1016/j.solener.2021.06.048
30.
de Vahl Davis
,
G.
,
1983
, “
Natural Convection of Air in a Square Cavity: A Bench Mark Numerical Solution
,”
Int. J. Numer. Methods Fluids
,
3
(
3
), pp.
249
264
.10.1002/fld.1650030305
31.
Markatos
,
N. C.
, and
Pericleous
,
K. A.
,
1984
, “
Laminar and Turbulent Natural Convection in an Enclosed Cavity
,”
Int. J. Heat Mass Transfer
,
27
(
5
), pp.
755
772
.10.1016/0017-9310(84)90145-5
32.
Geoola
,
F.
, and
Cornish
,
A. R. H.
,
1981
, “
Numerical Solution of Steady-State Free Convective Heat Transfer From a Solid Sphere
,”
Int. J. Heat Mass Transfer
,
24
(
8
), pp.
1369
1379
.10.1016/0017-9310(81)90187-3
33.
Shiina
,
Y.
,
Fujimura
,
K.
,
Kunugi
,
T.
, and
Akino
,
N.
,
1994
, “
Natural Convection in a Hemispherical Enclosure Heated From Below
,”
Int. J. Heat Mass Transfer
,
37
(
11
), pp.
1605
1617
.10.1016/0017-9310(94)90176-7
34.
Lewandowski
,
W. M.
,
Kubski
,
P.
,
Khubeiz
,
J. M.
,
Bieszk
,
H.
,
Wilczewski
,
T.
, and
Szymański
,
S.
,
1996
, “
Theoretical and Experimental Study of Natural Convection Heat Transfer From Isothermal Hemisphere
,”
Int. J. Heat Mass Transfer
,
40
(
1
), pp.
101
109
.10.1016/S0017-9310(96)00075-0
35.
Khubeiz
,
J. M.
,
Radziemska
,
E.
, and
Lewandowski
,
W. M.
,
2002
, “
Natural Convective Heat-Transfers From an Isothermal Horizontal Hemispherical Cavity
,”
Appl. Energy
,
73
(
3–4
), pp.
261
275
.10.1016/S0306-2619(02)00079-X
36.
Prakash
,
M.
,
Kedare
,
S. B.
, and
Nayak
,
J. K.
,
2012
, “
Numerical Study of Natural Convection Loss From Open Cavities
,”
Int. J. Therm. Sci.
,
51
, pp.
23
30
.10.1016/j.ijthermalsci.2011.08.012
37.
Baïri
,
A.
, and
Öztop
,
H. F.
,
2014
, “
On Thermal Control of Devices Contained in Inclined Hemispherical Cavities With Dome Oriented Downwards and Subjected to Transient Natural Convection
,”
Int. Commun. Heat Mass Transfer
,
55
, pp.
109
112
.10.1016/j.icheatmasstransfer.2014.04.001
38.
Baïri
,
A.
, and
de María
,
J. G.
,
2013
, “
Numerical and Experimental Study of Steady State Free Convection Generated by Constant Heat Flux in Tilted Hemispherical Cavities
,”
Int. J. Heat Mass Transfer
,
66
, pp.
355
365
.10.1016/j.ijheatmasstransfer.2013.07.038
39.
Baïri
,
A.
,
Monier-Vinard
,
E.
,
Laraqi
,
N.
,
Baïri
,
I.
,
Nguyen
,
M. N.
, and
Dia
,
C. T.
,
2014
, “
Natural Convection in Inclined Hemispherical Cavities With Isothermal Disk and Dome Faced Downwards. Experimental and Numerical Study
,”
Appl. Therm. Eng.
,
73
(
1
), pp.
1340
1347
.10.1016/j.applthermaleng.2014.09.012
40.
Baïri
,
A.
,
2014
, “
Quantification of Natural Convective Heat Transfer Within Air-Filled Hemispherical Cavities. Isothermal Tilted Disk With Dome Oriented Upwards and Wide Ra Range
,”
Int. Commun. Heat Mass Transfer
,
57
, pp.
291
296
.10.1016/j.icheatmasstransfer.2014.07.009
41.
Singh
,
B.
, and
Dash
,
S. K.
,
2015
, “
Natural Convection Heat Transfer From a Finned Sphere
,”
Int. J. Heat Mass Transfer
,
81
, pp.
305
324
.10.1016/j.ijheatmasstransfer.2014.10.028
42.
Zhang
,
J.
,
Zhen
,
Q.
,
Liu
,
J.
, and
Lu
,
W. Q.
,
2019
, “
Effect of Spacing on Laminar Natural Convection Flow and Heat Transfer From Two Spheres in Vertical Arrangement
,”
Int. J. Heat Mass Transfer
,
134
, pp.
852
865
.10.1016/j.ijheatmasstransfer.2019.01.065
43.
Lee
,
D.
,
Jang
,
H.
,
Lee
,
B. J.
,
Choi
,
W.
, and
Byon
,
C.
,
2019
, “
Internal Natural Convection Around a Sphere in a Rectangular Chamber
,”
Int. J. Heat Mass Transfer
,
136
, pp.
501
509
.10.1016/j.ijheatmasstransfer.2019.03.023
44.
Nazeer
,
M.
,
Ali
,
N.
,
Javed
,
T.
, and
Asghar
,
Z.
,
2018
, “
Natural Convection Through Spherical Particles of a Micropolar Fluid Enclosed in a Trapezoidal Porous Container
,”
Eur. Phys. J. Plus
,
133
(
10
), p.
423
.10.1140/epjp/i2018-12217-5
45.
Nazeer
,
M.
,
Ali
,
N.
, and
Javed
,
T.
,
2018
, “
Numerical Simulation of MHD Flow of Micropolar Fluid Inside a Porous Inclined Cavity With Uniform and Non-Uniform Heated Bottom Wall
,”
Can. J. Phys.
,
96
(
6
), pp.
576
593
.10.1139/cjp-2017-0639
46.
Nazeer
,
M.
,
Ali
,
N.
, and
Javed
,
T.
,
2018
, “
Natural Convection Flow of Micropolar Fluid Inside a Porous Square Conduit: Effects of Magnetic Field, Heat Generation/Absorption, and Thermal Radiation
,”
J. Porous Media
,
21
(
10
), pp.
953
975
.10.1615/JPorMedia.2018021123
47.
Ali
,
N.
,
Nazeer
,
M.
,
Javed
,
T.
, and
Siddiqui
,
M. A.
,
2018
, “
Buoyancy-Driven Cavity Flow of a Micropolar Fluid With Variably Heated Bottom Wall
,”
Heat Transfer Res.
,
49
(
5
), pp.
457
481
.10.1615/HeatTransRes.2018019422
48.
Nazeer
,
M.
,
Ali
,
N.
,
Javed
,
T.
, and
Razzaq
,
M.
,
2019
, “
Finite Element Simulations for Energy Transfer in a Lid-Driven Porous Square Container Filled With Micropolar Fluid: Impact of Thermal Boundary Conditions and Peclet Number
,”
Int. J. Hydrogen Energy
,
44
(
14
), pp.
7656
7666
.10.1016/j.ijhydene.2019.01.236
49.
Nazeer
,
M.
,
Ali
,
N.
, and
Javed
,
T.
,
2019
, “
Numerical Simulations of MHD Forced Convection Flow of Micropolar Fluid Inside a Right-Angled Triangular Cavity Saturated With Porous Medium: Effects of Vertical Moving Wall
,”
Can. J. Phys.
,
97
(
1
), pp.
1
13
.10.1139/cjp-2017-0904
50.
Nazir
,
M. W.
,
Javed
,
T.
,
Ali
,
N.
, and
Nazeer
,
M.
,
2021
, “
Effects of Radiative Heat Flux and Heat Generation on Magnetohydodynamics Natural Convection Flow of Nanofluid Inside a Porous Triangular Cavity With Thermal Boundary Conditions
,”
Numer. Methods Partial Differ. Equ.
, pp.
1
18
.10.1002/num.22768
51.
Ali
,
N.
,
Nazeer
,
M.
, and
Javed
,
T.
,
2021
, “
Finite Element Simulations of Free Convection Flow Inside a Porous Inclined Cavity Filled With Micropolar Fluid
,”
J. Porous Media
,
24
(
2
), pp.
57
75
.10.1615/JPorMedia.2020024977
52.
Saxena
,
A.
,
Kishor
,
V.
,
Singh
,
S.
, and
Srivastava
,
A.
,
2018
, “
Experimental and Numerical Study on the Onset of Natural Convection in a Cavity Open at the Top
,”
Phys. Fluids
,
30
(
5
), p.
057102
.10.1063/1.5025092
53.
Saxena
,
A.
,
Singh
,
S.
, and
Srivastava
,
A.
,
2018
, “
Flow and Heat Transfer Characteristics of an Open Cubic Cavity With Different Inclinations
,”
Phys. Fluids
,
30
(
8
), p.
087101
.10.1063/1.5040698
54.
Behera
,
B. R.
,
Chandrakar
,
V.
, and
Senapati
,
J. R.
,
2021
, “
Free Convection Heat Transfer From a Concave Hemispherical Surface: A Numerical Exercise
,”
Int. Commun. Heat Mass Transfer
,
125
, p.
105324
.10.1016/j.icheatmasstransfer.2021.105324
55.
Kishor
,
V.
,
Singh
,
S.
, and
Srivastava
,
A.
,
2021
, “
Flow Instabilities and Heat Transfer in a Differentially Heated Cavity Placed at Varying Inclination Angles: Non-Intrusive Measurements
,”
Phys. Fluids
,
33
(
9
), p.
094103
.10.1063/5.0063217
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