The present investigation proposes an innovative convergent double pipe heat exchanger (C-DPHE). A two-dimensional (2D) axisymmetric heat transfer model with counterflow is employed to analyze the thermal and hydraulic performance of this configuration numerically. The impact of convergence in the flow direction, using a wide range of contraction ratio (Cr), is explored. The effect of Reynolds and Prandtl numbers on the flow and heat transfer is addressed, as well. The model results were validated with available data from the literature, and an excellent agreement has been confirmed. In general, the findings of the present study indicate that increasing the contraction ratio increases heat transfer and pressure drop in the C-DPHE. Moreover, this configuration has a prominent and sustainable performance, compared to a conventional double pipe heat exchanger (DPHE), with an enhancement in heat transfer rate up to 32% and performance factor (PF) higher than one. Another appealing merit for the C-DPHE is that it is quite effective and functional at low Reynolds and high Prandtl numbers, respectively, since no high-operating pumping power is required. Further, the optimal operating conditions can be established utilizing the comprehensive information provided in this work.

References

References
1.
Al-Sammarraie
,
A. T.
, and
Vafai
,
K.
,
2017
, “
Heat Transfer Augmentation Through Convergence Angles in a Pipe
,”
Numer. Heat Transfer, Part A: Appl.
,
72
(
3
), pp.
197
214
.
2.
Syed
,
K. S.
,
Ishaq
,
M.
,
Iqbal
,
Z.
, and
Hassan
,
A.
,
2015
, “
Numerical Study of an Innovative Design of a Finned Double-Pipe Heat Exchanger With Variable Fin-Tip Thickness
,”
Energy Convers. Manage.
,
98
, pp.
69
80
.
3.
Kakac
,
S.
,
Liu
,
H.
, and
Pramuanjaroenkij
,
A.
,
2012
,
Heat Exchangers: Selection, Rating, and Thermal Design
,
3rd ed.
,
CRC Press, Taylor & Francis Group, LLC
,
Boca Raton, FL
.
4.
Prata
,
A. T.
, and
Sparrow
,
E. M.
,
1984
, “
Heat Transfer and Fluid Flow Characteristics for an Annulus of Periodically Varying Cross Section
,”
Numer. Heat Transfer
,
7
(
3
), pp.
285
304
.
5.
Agrawal
,
A. K.
, and
Sengupta
,
S.
,
1993
, “
Laminar Fluid Flow and Heat Transfer in an Annulus With an Externally Enhanced Inner Tube
,”
Int. J. Heat Fluid Flow
,
14
(
1
), pp.
54
63
.
6.
Syed
,
K. S.
,
Iqbal
,
M.
, and
Mir
,
N. A.
,
2007
, “
Convective Heat Transfer in the Thermal Entrance Region of Finned Double-Pipe
,”
Heat Mass Transfer
,
43
(
5
), pp.
449
457
.
7.
Syed
,
K. S.
,
Ishaq
,
M.
, and
Bakhsh
,
M.
,
2011
, “
Laminar Convection in the Annulus of a Double-Pipe With Triangular Fins
,”
Comput. Fluids
,
44
(
1
), pp.
43
55
.
8.
Syed
,
K. S.
,
Iqbal
,
Z.
, and
Ishaq
,
M.
,
2011
, “
Optimal Configuration of Finned Annulus in a Double Pipe With Fully Developed Laminar Flow
,”
Appl. Therm. Eng.
,
31
(
8–9
), pp.
1435
1446
.
9.
Iqbal
,
Z.
,
Syed
,
K. S.
, and
Ishaq
,
M.
,
2011
, “
Optimal Convective Heat Transfer in Double Pipe With Parabolic Fins
,”
Int. J. Heat Mass Transfer
,
54
(
25–26
), pp.
5415
5426
.
10.
Liu
,
S.
, and
Sakr
,
M.
,
2013
, “
A Comprehensive Review on Passive Heat Transfer Enhancements in Pipe Exchangers
,”
Renewable Sustainable Energy Rev.
,
19
, pp.
64
81
.
11.
Iqbal
,
Z.
,
Syed
,
K. S.
, and
Ishaq
,
M.
,
2015
, “
Fin Design for Conjugate Heat Transfer Optimization in Double Pipe
,”
Int. J. Therm. Sci.
,
94
, pp.
242
258
.
12.
Zohir
,
A. E.
,
Aziz
,
A. A. A.
, and
Habib
,
M. A.
,
2015
, “
Heat Transfer Characteristics and Pressure Drop of the Concentric Tube Equipped With Coiled Wires for Pulsating Turbulent Flow
,”
Exp. Therm. Fluid Sci.
,
65
, pp.
41
51
.
13.
Kamboj
,
K.
,
Singh
,
G.
,
Sharma
,
R.
,
Panchal
,
D.
, and
Hira
,
J.
,
2017
, “
Heat Transfer Augmentation in Double Pipe Heat Exchanger Using Mechanical Turbulators
,”
Heat Mass Transfer
,
53
(
2
), pp.
553
567
.
14.
Mahjoob
,
S.
, and
Vafai
,
K.
,
2008
, “
A Synthesis of Fluid and Thermal Transport Models for Metal Foam Heat Exchangers
,”
Int. J. Heat Mass Transfer
,
51
(
15–16
), pp.
3701
3711
.
15.
Targui
,
N.
, and
Kahalerras
,
H.
,
2008
, “
Analysis of Fluid Flow and Heat Transfer in a Double Pipe Heat Exchanger With Porous Structures
,”
Energy Convers. Manage.
,
49
(
11
), pp.
3217
3229
.
16.
Targui
,
N.
, and
Kahalerras
,
H.
,
2013
, “
Analysis of a Double Pipe Heat Exchanger Performance by Use of Porous Baffles and Pulsating Flow
,”
Energy Convers. Manage.
,
76
, pp.
43
54
.
17.
Chen
,
X.
,
Tavakkoli
,
F.
, and
Vafai
,
K.
,
2015
, “
Analysis and Characterization of Metal Foam-Filled Double-Pipe Heat Exchangers
,”
Numer. Heat Transfer, Part A: Appl.
,
68
(
10
), pp.
1031
1049
.
18.
Duangthongsuk
,
W.
, and
Wongwises
,
S.
,
2009
, “
Heat Transfer Enhancement and Pressure Drop Characteristics of TiO2–Water Nanofluid in a Double-Tube Counter Flow Heat Exchanger
,”
Int. J. Heat Mass Transfer
,
52
(
7–8
), pp.
2059
2067
.
19.
Huminic
,
G.
, and
Huminic
,
A.
,
2011
, “
Heat Transfer Characteristics in Double Tube Helical Heat Exchangers Using Nanofluids
,”
Int. J. Heat Mass Transfer
,
54
(
19–20
), pp.
4280
4287
.
20.
Darzi
,
A. R.
,
Farhadi
,
M.
, and
Sedighi
,
K.
,
2013
, “
Heat Transfer and Flow Characteristics of AL2O3–Water Nanofluid in a Double Tube Heat Exchanger
,”
Int. Commun. Heat Mass Transfer
,
47
, pp.
105
112
.
21.
Mohammed
,
H. A.
,
Hasan
,
H. A.
, and
Wahid
,
M. A.
,
2013
, “
Heat Transfer Enhancement of Nanofluids in a Double Pipe Heat Exchanger With Louvered Strip Inserts
,”
Int. Commun. Heat Mass Transfer
,
40
, pp.
36
46
.
22.
Sonawane
,
S. S.
,
Khedkar
,
R. S.
, and
Wasewar
,
K. L.
,
2013
, “
Study on Concentric Tube Heat Exchanger Heat Transfer Performance Using Al2O3–Water Based Nanofluids
,”
Int. Commun. Heat Mass Transfer
,
49
, pp.
60
68
.
23.
Khedkar
,
R. S.
,
Sonawane
,
S. S.
, and
Wasewar
,
K. L.
,
2013
, “
Water to Nanofluids Heat Transfer in Concentric Tube Heat Exchanger: Experimental Study
,”
Procedia Eng.
,
51
, pp.
318
323
.
24.
Khedkar
,
R. S.
,
Sonawane
,
S. S.
, and
Wasewar
,
K. L.
,
2014
, “
Heat Transfer Study on Concentric Tube Heat Exchanger Using TiO2–Water Based Nanofluid
,”
Int. Commun. Heat Mass Transfer
,
57
, pp.
163
169
.
25.
Sözen
,
A.
,
Variyenli
,
H. İ.
,
Özdemir
,
M. B.
,
Gürü
,
M.
, and
Aytaç
,
İ.
,
2016
, “
Heat Transfer Enhancement Using Alumina and Fly Ash Nanofluids in Parallel and Cross-Flow Concentric Tube Heat Exchangers
,”
J. Energy Inst.
,
89
(
3
), pp.
414
424
.
26.
Ekkad
,
S. V.
,
Pamula
,
G.
, and
Shantiniketanam
,
M.
,
2000
, “
Detailed Heat Transfer Measurements Inside Straight and Tapered Two-Pass Channels With Rib Turbulators
,”
Exp. Therm. Fluid Sci.
,
22
(
3–4
), pp.
155
163
.
27.
Mahjoob
,
S.
, and
Vafai
,
K.
,
2009
, “
Analytical Characterization and Production of an Isothermal Surface for Biological and Electronic Applications
,”
ASME J. Heat Transfer
,
131
(
5
), p.
052604
.
28.
Mahjoob
,
S.
, and
Vafai
,
K.
,
2011
, “
Analysis of Heat Transfer in Consecutive Variable Cross-Sectional Domains: Applications in Biological Media and Thermal Management
,”
ASME J. Heat Transfer
,
133
(
1
), p.
011006
.
29.
Nilson
,
R. H.
,
Griffiths
,
S. K.
,
Tchikanda
,
S. W.
, and
Martinez
,
M. J.
,
2004
, “
Axially Tapered Microchannels of High Aspect Ratio for Evaporative Cooling Devices
,”
ASME J. Heat Transfer
,
126
(
3
), pp.
453
462
.
30.
Osanloo
,
B.
,
Mohammadi-Ahmar
,
A.
,
Solati
,
A.
, and
Baghani
,
M.
,
2016
, “
Performance Enhancement of the Double-Layered Micro-Channel Heat Sink by Use of Tapered Channels
,”
Appl. Therm. Eng.
,
102
, pp.
1345
1354
.
31.
Vafai
,
K.
, and
Zhu
,
L.
,
1999
, “
Analysis of Two-Layered Micro-Channel Heat Sink Concept in Electronic Cooling
,”
Int. J. Heat Mass Transfer
,
42
(
12
), pp.
2287
2297
.
32.
Wong
,
K. C.
, and
Ang
,
M. L.
,
2017
, “
Thermal Hydraulic Performance of a Double-Layer Microchannel Heat Sink With Channel Contraction
,”
Int. Commun. Heat Mass Transfer
,
81
, pp.
269
275
.
33.
Bejan
,
A.
,
2000
,
Shape and Structure, From Engineering to Nature
,
Cambridge University Press
,
Cambridge, UK
.
34.
Bejan
,
A.
,
2013
,
Convection Heat Transfer
,
4th ed.
,
Wiley,
Hoboken, NJ
.
35.
Shah
,
R. K.
, and
Bhatti
,
M. S.
,
1987
, “
Laminar Convective Heat Transfer in Ducts
,”
Handbook of Single-phase Convective Heat Transfer
,
S.
Kakaç
,
R. K.
Shah
, and
W.
Aung
, eds.,
Wiley
,
New York
, Chap. 3.
36.
Lundberg
,
R. E.
,
McCuen
,
P. A.
, and
Reynolds
,
W. C.
,
1963
, “
Heat Transfer in Annular Passages. Hydrodynamically Developed Laminar Flow With Arbitrarily Prescribed Wall Temperatures or Heat Fluxes
,”
Int. J. Heat Mass Transfer
,
6
(
6
), pp.
495
529
.
37.
Kakac
,
S.
, and
Yener
,
Y.
,
1995
,
Convective Heat Transfer
,
2nd ed.
,
CRC Press,
Boca Raton, FL
.
38.
Bejan
,
A.
,
Alalaimi
,
M.
,
Sabau
,
A. S.
, and
Lorente
,
S.
,
2017
, “
Entrance-Length Dendritic Plate Heat Exchangers
,”
Int. J. Heat Mass Transfer
,
114
, pp.
1350
1356
.
39.
Webb
,
R. L.
,
1994
,
Principles of Enhanced Heat Transfer
,
Wiley,
New York
.
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