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- 1. International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 –
6480(Print), ISSN 0976 – 6499(Online) Volume 5, Issue 4, April (2014), pp. 31-37 © IAEME
31
AN EXPERIMENTAL STUDY OF HEAT TRANSFER IN A PLATE HEAT
EXCHANGER
Omar Mohammed Ismael*, Dr. Ajeet Kumar Rai**, HasanFalah Mahdi*, Vivek Sachan**
*Ministry of Higher Education and Scientific Research, Republic of Iraq
**Department of Mechanical Engineering, SSET, SHIATS-DU, Allahabad (U.P) INDIA-211007
ABSTRACT
Experiments were conducted to determine the laminar convective heat transfer characteristics
for fully developed flow of hot and cold fluid in alternate ducts. Experiments were conducted on a
three channel 1-1 pass plate heat exchanger. Hot fluid was made to flow in the central channel to get
cooled by water in the outer channels in parallel and counter flow arrangements. Reynolds number
was fixed at 1666.5 for milk and for the cooling water also. The average heat transfer coefficient of
the milk-water system is 17% higher compared with water-water system in the counter flow
arrangement.
Key words: Plate Heat Exchanger, Heat Transfer Coefficient.
INTRODUCTION
A heat exchanger is a device that is used to transfer thermal energy (enthalpy) between two or
more fluids, between a solid surface and a fluid, or between solid particulates and a fluid, at different
temperatures and in thermal contact. In heat exchangers, there are usually no external heat and work
interactions. Typical applications involve heating or cooling of a fluid stream of concern and
evaporation or condensation of single- or multi component fluid streams. In other applications, the
objective may be to recover or reject heat, or sterilize, pasteurize, fractionate, distill, concentrate,
crystallize, or control process fluid. In a few heat exchangers, the fluids exchanging heat are in direct
contact. In most heat exchangers, heat transfer between fluids takes place through a separating wall
or into and out of a wall in a transient manner. In many heat exchangers, the fluids are separated by a
heat transfer surface, and ideally they do not mix or leak. Such exchangers are referred to as direct
transfer type, or simply recuperate. In contrast, exchangers in which there is intermittent heat
exchange between the hot and cold fluids—via thermal energy storage and release through the
exchanger surface or matrix are referred to as indirect transfer type, or simply regenerators. Such
INTERNATIONAL JOURNAL OF ADVANCED RESEARCH IN ENGINEERING
AND TECHNOLOGY (IJARET)
ISSN 0976 - 6480 (Print)
ISSN 0976 - 6499 (Online)
Volume 5, Issue 4, April (2014), pp. 31-37
© IAEME: www.iaeme.com/ijaret.asp
Journal Impact Factor (2014): 7.8273 (Calculated by GISI)
www.jifactor.com
IJARET
© I A E M E
- 2. International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 –
6480(Print), ISSN 0976 – 6499(Online) Volume 5, Issue 4, April (2014), pp. 31-37 © IAEME
32
exchangers usually have fluid leakage from one fluid stream to the other, due to pressure differences
and matrix rotation/valve switching. Common examples of heat exchangers are shell-and tube
exchangers, automobile radiators, condensers, evaporators, air pre-heaters, and cooling towers. If no
phase change occurs in any of the fluids in the exchanger, it is sometimes referred to as a sensible
heat exchanger. There could be internal thermal energy sources in the exchangers, such as in electric
heaters and nuclear fuel elements. Combustion and chemical reaction may take place within the
exchanger, such as in boilers, fired heaters, and fluidized-bed exchangers. Mechanical devices may
be used in some exchangers such as in scraped surface exchangers, agitated vessels, and stirred tank
reactors(1) and the detailed of classification is given by shah (2). Heat exchangers are devices used
to transfer heat between two or more fluid streams at different temperatures. Heat exchangers find
widespread use in power generation, chemical processing, electronics cooling, air-conditioning,
refrigeration, and automotive applications. A plate type heat exchanger, as compared to a similar
sized tube and shell heat exchanger, is capable of transferring much more heat. This is due to the
large area that plates provide over tubes .Plate heat exchangers are used for transferring heat for any
combination of gas, liquid and two-phase streams. Plate heat exchangers can be classified as
casketed plate, spiral plate or lamella(3).Extended surface heat exchanger Extended surface heat
exchangers are generally fins or appendages added to the primary heat transfer surface (tubular or
plate) with the aim of increasing the heat transfer area. The two most common types of extended
surface heat exchangers are plate-fin heat exchangers and tube-fin heat exchangers. Consist of a
stack of parallel thin plates that lie between heavy end plates. Each fluid stream passes alternately
between adjoining plates in the stack, exchanging heat through the plates. The plates are corrugated
for strength and to enhance heat transfer by directing the flow and increasing turbulence. These
exchangers have high heat-transfer coefficients and area, the pressure drop is also typically low, and
they often provide very high effectiveness. However, they have relatively low pressure capability. A
plate type heat exchanger consists of plates instead of tubes to separate the hot and cold fluids.
EXPERIMENTAL SETUP AND PROCEDURE
The photograph of the experimental setup, fabricated to investigate the heat transfer
characteristics of the plate heat exchanger channels for same flow conditions are shown in (Fig.1).It
includes a hot water loop, a coolant loop and a measurement system. The hot water loop and coolant
loop comprise water tanks containing heater, pump and temperature indicator. A flow straightener is
installed at the entrance and exit of the test section to maintain the uniformity of the flow. The test
section of the plate heat exchanger has three ducts. The geometrical characteristics are given in the
table1.
Two different cases of parallel and counter flow arrangements have been made. Hot fluid
(milk) was made to flow through the central channel and cold fluid (water) through the two outer
channels. Copper-Constantan thermocouples are used to measure the temperature of the fluids at the
inlet and outlet of the heat exchanger.
Table 1: Geometrical characteristics of plate heat exchanger
Sl. No Parameters Value
1 Length of the test section, L 100 cm
2 Width of the test section, a 10 cm
3 High of the test section, b 5 cm
- 3. International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 –
6480(Print), ISSN 0976 – 6499(Online) Volume 5, Issue 4, April (2014), pp. 31-37 © IAEME
33
Fig.1: Plate Heat Exchanger
The experimental data was used to calculate the heat exchanger rate, convective heat transfer
coefficient, Nusselt number and Peclet number of each of the involved fluids. Heat removal rate;
Heat transferred from an elemental part of the exchanger is:
The local heat transfer coefficients for the fluids are determined from:
where the bulk temperature is given by,
the average heat transfer coefficient by,
Therefore, it can be shown that
Each channel has equal flow area and wetted perimeter givenby,
And hence hydraulic diameter of the channel is given by, Dh = 4Ao/P with appropriate second suffix
in flow area. The relevant flow- and fluid-properties are found from Specific flow rates for the fluids;
Reynolds number of the fluids;
The overall heat transfer coefficient
Observations and Results: Experimentation is done with hot fluid as milk and as water separately
with cold fluid as water in parallel and counter flow arrangements.Numbers of observations were
taken on the setup for a fixed inlet temperature of hot and cold fluids. Values are tabulated as shown
below.
- 4. International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 –
6480(Print), ISSN 0976 – 6499(Online) Volume 5, Issue 4, April (2014), pp. 31-37 © IAEME
34
Table 2: The temperature and properties for counter flow with hot milk in the Centre
Thi Tho Tci Tco ρρρρ
kg/m2
Cph
kJ/kg K
K
W/mK
µ
Ns/m
Cpc
kJ/kg K
70 55 35 36 1.02998 1009.7543 0.02977 0.00002 1004.3509
70 55 35 36 1.02998 1009.7543 0.02977 0.00002 1004.3509
70 56 35 37 1.02998 1009.7543 0.02977 0.00002 1004.3509
70 56 35 38 1.02998 1009.7543 0.02977 0.00002 1004.3509
70 55 35 37 1.02998 1009.7543 0.02977 0.00002 1004.3509
70 55 35 37 1.02998 1009.7543 0.02977 0.00002 1004.3509
70 55 35 37 1.02998 1009.7543 0.02977 0.00002 1004.3509
Table 3: The temperature and properties for parallel flow with hot milk in the Centre
Thi Tho Tci Tco ρρρρ
kg/m2
Cph
kJ/kg K
K
W/mK
µ
Ns/m
Cpc
kJ/kg K
70 58 33 37 1.02998 1009.7543 0.02977 0.00002 1004.0496
70 58 33 37 1.02998 1009.7543 0.02977 0.00002 1004.0496
70 59 33 38 1.02998 1009.7543 0.02977 0.00002 1004.0496
70 59 33 39 1.02998 1009.7543 0.02977 0.00002 1004.0496
70 59 33 39 1.02998 1009.7543 0.02977 0.00002 1004.0496
70 58 33 38 1.02998 1009.7543 0.02977 0.00002 1004.0496
70 58 33 38 1.02998 1009.7543 0.02977 0.00002 1004.0496
Table 4: The temperature and properties for parallel flow with hot water in the Centre
Thi Tho Tci Tco ρρρρ
kg/m2
Cph
kJ/kg K
K
W/mK
µ
Ns/m
Cpc
kJ/kg K
70 48 28 32 1.02998 1009.7543 0.02977 0.00002 1003.30035
70 48 28 32 1.02998 1009.7543 0.02977 0.00002 1003.30035
70 48 28 33 1.02998 1009.7543 0.02977 0.00002 1003.30035
70 49 28 33 1.02998 1009.7543 0.02977 0.00002 1003.30035
70 49 28 34 1.02998 1009.7543 0.02977 0.00002 1003.30035
70 49 28 34 1.02998 1009.7543 0.02977 0.00002 1003.30035
70 49 28 34 1.02998 1009.7543 0.02977 0.00002 1003.30035
Table 5: The temperature and properties counter for flow with hot water in the Centre
Thi Tho Tci Tco ρρρρ
kg/m2
Cph
kJ/kg K
K
W/mK
µ
Ns/m
Cpc
kJ/kg K
70 54 34 39 1.02998 1009.7543 0.02977 0.00002 1004.2001
70 56 34 43 1.02998 1009.7543 0.02977 0.00002 1004.2001
70 57 34 45 1.02998 1009.7543 0.02977 0.00002 1004.2001
70 57 34 47 1.02998 1009.7543 0.02977 0.00002 1004.2001
70 58 34 48 1.02998 1009.7543 0.02977 0.00002 1004.2001
70 59 34 48 1.02998 1009.7543 0.02977 0.00002 1004.2001
70 59 34 48 1.02998 1009.7543 0.02977 0.00002 1004.2001
- 5. International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 –
6480(Print), ISSN 0976 – 6499(Online) Volume 5, Issue 4, April (2014), pp. 31-37 © IAEME
35
Table 6: Result for parallel flow with hot water in the Centre
Re V
m/s
LMTD
C, k
h
W
/m2
.K
Nu εεεε
Effectiveness
Heat flow
Q( w )
1666.5 0.0485 26.9407 98.485 2265.61 0.5271 5553.64
1666.5 0.0485 26.9407 98.485 2265.61 0.5271 5553.64
1666.5 0.0485 26.223 101.18 2327.6 0.5272 5553.64
1666.5 0.0485 26.9407 94.009 2162.63 0.5032 5301.21
1666.5 0.0485 26.223 96.581 2221.8 0.5032 5301.21
1666.5 0.0485 26.223 96.581 2221.8 0.5032 5301.21
1666.5 0.0485 26.223 96.581 2221.8 0.5032 5301.21
Table 7: Result for counter flow with hot water in the Centre
Re V
m/s
LMTD
C, k
h
W /m2
.K
Nu εεεε
Effectiveness
Heat flow
Q( w )
1666.5 0.0485 24.663 78.241 1799.89 0.4469 4039.02
1666.5 0.0485 25.323 60.676 1533.85 0.391 3534.14
1666.5 0.0485 25.968 60.374 1388.89 0.3631 3281.7
1666.5 0.0485 25.968 60.374 1388.89 0.3631 3281.7
1666.5 0.0485 25.968 55.7307 1282.05 0.3351 3029.26
1666.5 0.0485 27.2207 48.736 1121.15 0.3072 2776.82
1666.5 0.0485 27.2207 48.736 1121.15 0.3072 2776.82
Table 8: Result for counter flow with hot milk in the Centre
Re V
m/s
LMTD
C, k
h
W
/m2
.K
Nu εεεε
Effectiveness
Heat flow
Q( w )
1666.5 0.0485 26.1904 69.073 1588.98 0.4308 3786.57
1666.5 0.0485 26.1904 69.073 1588.98 0.4308 3786.57
1666.5 0.0485 26.1904 64.468 1483.05 0.4021 3534.14
1666.5 0.0485 25.564 66.045 1519.35 0.4021 3534.14
1666.5 0.0485 25.564 70.763 1627.87 0.4308 3786.57
1666.5 0.0485 25.564 70.763 1627.87 0.4308 3786.57
1666.5 0.0485 25.564 70.763 1627.87 0.4308 3786.57
Table 9: Result for parallel flow with hot milk in the Centre
Re V
m/s
LMTD
C, k
h
W
/m2
.K
Nu εεεε
Effectiveness
Heat flow
Q( w )
1666.5 0.0485 28.248 51.113 1144.5 0.3261 3022.22
1666.5 0.0485 28.248 51.113 1144.5 0.3261 3022.22
1666.5 0.0485 28.248 46.853 1049.13 0.298 2770.37
1666.5 0.0485 27.633 47.896 1022.47 0.2989 2770.37
1666.5 0.0485 27.633 47.896 1022.47 0.2989 2770.37
1666.5 0.0485 27.633 52.250 1169.97 0.3261 3022.22
1666.5 0.0485 27.633 52.250 1169.97 0.3261 3022.22
- 6. International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 –
6480(Print), ISSN 0976 – 6499(Online) Volume 5, Issue 4, April (2014), pp. 31-37 © IAEME
36
CONCLUSIONS
An experimental set up of heat exchanger was made of Al sheet for heat transfer study. The
test section was formed by three identical channels with hot fluid in the middle and cold fluid in the
adjacent channels. A milk-water and water-water fluid combinations are selected in parallel and
counter flow arrangements of the heat exchanger. It is observed that counter flow arrangement of
milk-water combinations is 29.4% more effective than their parallel flow arrangements. Further,
milk-water fluid combination in counter flow is 13.2% more effective than water-water fluid
combination.
Future scope of work: The rate of heat transfer rate can be further increased by having high thermal
conductivity fluids or by use of Nano particles of high thermal conductivity materials in the het
transfer fluids. Plates of the plate heat exchangers can be corrugated at suitable angles to enhance the
heat transfer between the fluids.
REFERENCES
1. Shah, R. K. andSekulic D. P. 2003“Fundamentals of Heat Exchanger Design” John Wiley
&Sons,Inc
2. Shah, R. K., 1981, Classification of heat exchangers, in Heat Exchangers: Thermal-
Hydraulic Fundamentals and Design, S. Kakac¸ , A. E. Bergles, and F. Mayinger, eds.,
Hemisphere Publishing,Washington, DC, pp. 9–46.
3. SadikKakaç, Hongtan Liu 2002. Heat Exchangers: Selection, Rating, and Thermal Design,
Second Edition,CRC Press
4. Shah, R. K., 1991, Industrial heat exchangers—functions and types, in Industrial Heat
Exchangers,J-M. Buchlin, ed., Lecture Series No. 1991-04, von Ka´rma´n Institute for Fluid
Dynamics, Belgium.
5. Shah, R. K., 1994, Heat exchangers, in Encyclopedia of Energy Technology and the
Environment, A.Bisio and S. G. Boots, eds., Wiley, New York, pp. 1651–1670.
6. Shah, R. K., and W. W. Focke, 1988, Plate heat exchangers and their design theory, in Heat
TransferEquipment Design, R. K. Shah, E. C. Subbarao, and R. A. Mashelkar, eds.,
Hemisphere Publishing,Washington, DC, pp. 227–254.
7. Bejan, A.,Heat Transfer, 1993, Wiley, New York, NY.
8. Kakac, S. (ed.),Boilers, Evaporators, and Condensers, 1991, Wiley, New York,NY.
9. Kakac, S. and Liu, H., Heat Exchangers: Selection, Rating, and Thermal Performance,
1998, CRC Press, Boca Raton, FL.
10. Kays, W.M. and London, A.L.,Compact Heat Exchangers, 1984, McGraw-Hill, New York,
NY.
11. Kern, D.Q. and Kraus, A.D., Extended Surface Heat Transfer, 1972, McGraw-Hill, New
York, NY.
12. L. B.Wang, Y. H. Zhang, Y. X. Su, and S. D. Gao, “Local and Average Heat/Mass
Transfer over Flat Tube Bank Fin Mounted In-Line Vortex Generators with Small
Longitudinal Spacing”, Journal of Enhanced Heat Transfer ,Vol. 9, pp.77–87, (2002).
13. W. R. Pauley and J. K. Eaton, “ The Effect of Embedded Longitudinal Vortex Arrays on
Turbulent Boundary Layer Heat Transfer”, Transactions Of The ASME, Journal Of Heat
Transfer, Vol.116, pp.871-878,(1994).
14. Han,J.C. ,“Heat transfer and friction in channels with two opposite rib-roughened walls. ”,
Transaction of the ASME, Vol. 106, Nov,(1984).
- 7. International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN
6480(Print), ISSN 0976 – 6499(Online) Volume 5, Issue 4, April (2014), pp.
15. Mustafa S Mahdi and Ajeet Kumar Rai
of single phase liquid to liquid shell and tube heat exchanger’’
Mechanical Engineering & Technology
16. ShiveDayalPandey, V.K. Nema
of nanofluids a coolant in a corrugated plate heat exchanger “
science 38 (2012) 248–256
17. Shah, R. K., 1991, Compact heat exchanger technology and applications, in Heat Exchanger
Engineering, Vol. 2, Compact Heat Exchangers: Techniques for Size Reduction, E. A.
Foumeny P. J. Heggs, eds., Ellis Horwood, London, pp. 1
18. N.G.Narve and N.K.Sane,
Symmetrical Triangular Fin Arrays”, International Journal of Advanced Research in
Engineering & Technology (IJARET), Volume 4, Issue 2, 2013, pp. 271
0976-6480, ISSN Online: 0976
19. Ajeet Kumar Rai, Shahbaz Ahmad and Sarfaraj Ahamad Idrisi,
and Heat Transfer Study o
Engineering & Technology (IJMET), Volume
0976 – 6340, ISSN Online: 0976
AUTHOR’S DETAIL
Omar Mohammed
B.Sc. in the year 2010
conditioning Eng. Tech
education and scientific research
in 2014 in Mechanical
School of Engineering and Technology,
Agriculture Technology & S
Dr. A. K. Rai
his M.Tech Degree from MNNIT Allahabad in Design of Process Machines
and Ph.D. from SHIATS
PantNagar from 2003 to 2005. He ha
assistant Profes
international journals. He has delivered expert lectures in many national and
International conferences.
International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN
6499(Online) Volume 5, Issue 4, April (2014), pp. 31-37 © IAEME
37
Mustafa S Mahdi and Ajeet Kumar Rai “A practical approach to design and optimization
of single phase liquid to liquid shell and tube heat exchanger’’ International Journal
Mechanical Engineering & Technology, 3(3), 378 – 386 (2012).
V.K. Nema “Experimental analysis of heat transfer and friction factor
of nanofluids a coolant in a corrugated plate heat exchanger “Experimental thermal and fluid
, Compact heat exchanger technology and applications, in Heat Exchanger
Engineering, Vol. 2, Compact Heat Exchangers: Techniques for Size Reduction, E. A.
Foumeny P. J. Heggs, eds., Ellis Horwood, London, pp. 1–29.
N.G.Narve and N.K.Sane, “Heat Transfer and Fluid Flow Characteristics of Vertical
Symmetrical Triangular Fin Arrays”, International Journal of Advanced Research in
echnology (IJARET), Volume 4, Issue 2, 2013, pp. 271 -
6480, ISSN Online: 0976-6499.
Ajeet Kumar Rai, Shahbaz Ahmad and Sarfaraj Ahamad Idrisi, “Design, Fabrication
of Green House Dryer”, International Journal of Mechanical
Engineering & Technology (IJMET), Volume 4, Issue 4, 2013, pp. 1 -
6340, ISSN Online: 0976 – 6359.
ohammed Ismael is born in Baghdad in April 1987, he received his
in the year 2010 from the department of Refrigeration and Air
ditioning Eng. TechTechnical College,of Baghdad,Ministry of higher
ucation and scientific research, Republic of Iraq. He completed
in Mechanical Engineering (Thermal Engineering) form
School of Engineering and Technology, Sam Higginbottom Institute of
culture Technology & Sciences, Allahabad, U.P, India.
is born in 1977, Distt. Ballia (Uttar Pradesh) India. He received
his M.Tech Degree from MNNIT Allahabad in Design of Process Machines
and Ph.D. from SHIATS- DU Allahabad in2011. He has been in GBPUAT
PantNagar from 2003 to 2005. He has Joined SHIATS-DU Allahabad as
assistant Professor in2005. He has published more than 25 papers in
international journals. He has delivered expert lectures in many national and
International conferences.
International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 –
© IAEME
practical approach to design and optimization
International Journal of
xperimental analysis of heat transfer and friction factor
xperimental thermal and fluid
, Compact heat exchanger technology and applications, in Heat Exchanger
Engineering, Vol. 2, Compact Heat Exchangers: Techniques for Size Reduction, E. A.
“Heat Transfer and Fluid Flow Characteristics of Vertical
Symmetrical Triangular Fin Arrays”, International Journal of Advanced Research in
281, ISSN Print:
“Design, Fabrication
International Journal of Mechanical
- 7, ISSN Print:
April 1987, he received his
the department of Refrigeration and Air-
Ministry of higher
e completed his M .Tech.
Engineering (Thermal Engineering) form Shepherd
igginbottom Institute of
lia (Uttar Pradesh) India. He received
his M.Tech Degree from MNNIT Allahabad in Design of Process Machines
He has been in GBPUAT
DU Allahabad as
sor in2005. He has published more than 25 papers in
international journals. He has delivered expert lectures in many national and