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International Journal of Mechanical Engineering and Technology (IJMET)Volume 8, Issue 5, May 2017, pp.
Available online at http://www.iaeme.com/IJME
ISSN Print: 0976-6340 and ISSN Online: 0976
© IAEME Publication
NUMERICAL INVESTIGAT
TRANSFER AND FLUID FL
HEAT EXC
TYPES OF PLATE MAT
D.V.Sai Teja and Dr Y.V.Hanumantha Rao
Department of Mechanical Engineering KL
ABSTRACT
Numerical investigation of heat transfer and fluid flow in a single pass counter
flow chevron corrugated platesplate heat exchanger considering methanol as hot fluid
and water as cold fluid with different types
this paper using commercial CFD software, ANSYS Fluent. The results of numerical
simulation were compared with experimental data in order to verify the accuracy of
the model. CFD simulations
plate material increases the heat transfer rate comparing to Aluminium and Inconel
718 and it also shows that corrugation pattern of the plate develops turbulence and
vortices of fluid which results in high heat transfer rates.
Key Words: Plate Heat Exchanger, Corrugated pattern, CFD Analysis
Cite this Article: D.V.Sai Teja and Dr Y.V.Hanumantha Rao Numerical Investigation
of Heat Transfer and Fluid Flow in Plate Heat Exchanger With Different Types of
Plate Materials. International Jour
8(5), 2017, pp. 621–637.
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1. INTRODUCTION
The plate heat exchanger consists of a pack of corrugated metal plates with portholes for the
passage of the two fluids between which heat transfer will take place
KumarTiwari [1] and also the plate pack is assembled between a fix frame plate and a
movable pressure plate and compressed by tightening bolts. The number of plates is
determined by the flow rate, physical properties of the fluids, pressure drop and temperature
program. The plate corrugations promote fluid turbulence and support the plates against
differential pressure. It is designed in such a way that cold fluid and hot fluid fl
surface of the alternate plates that is cold fluid flows of in the first column between the two
plates, hot fluid in the second column, cold fluid in third column e.tc., so that cold fluid flows
on one side of the plate and hot fluid on the othe
thin having corrugations heat transfer takes place between the two fluids. Here the model is
IJMET/index.asp 621 [email protected]
International Journal of Mechanical Engineering and Technology (IJMET) 2017, pp. 621–637, Article ID: IJMET_08_05_068
http://www.iaeme.com/IJMET/issues.asp?JType=IJMET&VType=8&IType=5
N Online: 0976-6359
Scopus Indexed
UMERICAL INVESTIGATION OF HEAT
RANSFER AND FLUID FLOW IN PLATE
HEAT EXCHANGER WITH DIFFEREN
TYPES OF PLATE MATERIALS
D.V.Sai Teja and Dr Y.V.Hanumantha Rao
Department of Mechanical Engineering KL University,Vaddeswaram, AP, India.
Numerical investigation of heat transfer and fluid flow in a single pass counter
flow chevron corrugated platesplate heat exchanger considering methanol as hot fluid
and water as cold fluid with different types of plate materials has been presented in
this paper using commercial CFD software, ANSYS Fluent. The results of numerical
simulation were compared with experimental data in order to verify the accuracy of
the model. CFD simulations and Numerical analysis shows that using of Copper as
plate material increases the heat transfer rate comparing to Aluminium and Inconel
718 and it also shows that corrugation pattern of the plate develops turbulence and
vortices of fluid which results in high heat transfer rates.
Plate Heat Exchanger, Corrugated pattern, CFD Analysis.
D.V.Sai Teja and Dr Y.V.Hanumantha Rao Numerical Investigation
of Heat Transfer and Fluid Flow in Plate Heat Exchanger With Different Types of
International Journal of Mechanical Engineering and Technology
com/IJMET/issues.asp?JType=IJMET&VType=8&IType=5
The plate heat exchanger consists of a pack of corrugated metal plates with portholes for the
f the two fluids between which heat transfer will take place
the plate pack is assembled between a fix frame plate and a
movable pressure plate and compressed by tightening bolts. The number of plates is
by the flow rate, physical properties of the fluids, pressure drop and temperature
program. The plate corrugations promote fluid turbulence and support the plates against
differential pressure. It is designed in such a way that cold fluid and hot fluid fl
surface of the alternate plates that is cold fluid flows of in the first column between the two
plates, hot fluid in the second column, cold fluid in third column e.tc., so that cold fluid flows
on one side of the plate and hot fluid on the other side of the same plate as the plate is very
thin having corrugations heat transfer takes place between the two fluids. Here the model is
T&VType=8&IType=5
ION OF HEAT
OW IN PLATE
HANGER WITH DIFFERENT
ERIALS
Vaddeswaram, AP, India.
Numerical investigation of heat transfer and fluid flow in a single pass counter
flow chevron corrugated platesplate heat exchanger considering methanol as hot fluid
of plate materials has been presented in
this paper using commercial CFD software, ANSYS Fluent. The results of numerical
simulation were compared with experimental data in order to verify the accuracy of
hows that using of Copper as
plate material increases the heat transfer rate comparing to Aluminium and Inconel-
718 and it also shows that corrugation pattern of the plate develops turbulence and
.
D.V.Sai Teja and Dr Y.V.Hanumantha Rao Numerical Investigation
of Heat Transfer and Fluid Flow in Plate Heat Exchanger With Different Types of
nal of Mechanical Engineering and Technology,
com/IJMET/issues.asp?JType=IJMET&VType=8&IType=5
The plate heat exchanger consists of a pack of corrugated metal plates with portholes for the
as given by Arun
the plate pack is assembled between a fix frame plate and a
movable pressure plate and compressed by tightening bolts. The number of plates is
by the flow rate, physical properties of the fluids, pressure drop and temperature
program. The plate corrugations promote fluid turbulence and support the plates against
differential pressure. It is designed in such a way that cold fluid and hot fluid flows on the
surface of the alternate plates that is cold fluid flows of in the first column between the two
plates, hot fluid in the second column, cold fluid in third column e.tc., so that cold fluid flows
r side of the same plate as the plate is very
thin having corrugations heat transfer takes place between the two fluids. Here the model is
Numerical Investigation of Heat Transfer and Fluid Flow in Plate Heat Exchanger With Different Types of
Plate Materials
http://www.iaeme.com/IJMET/index.asp 622 [email protected]
made in CATIA and CFD Simulation is used to investigate the heat transfer and fluid flow in
PHE with only one plate. Computational Fluid Dynamics (CFD) is the science of predicting
fluid flow, heat and mass transfer, chemical reactions, and related phenomena by solving
numerically the set of governing mathematical equations which is stated in the ANSYS
training module in second slide [2]
2. LITERATURE REVIEW
A laboratory experimental facility was constructed and the thermal-hydraulic characteristics
of three middle-size industrial PHE’s were measured. The exchangers all had 24 plates of the
same size but with different chevron angle combinations of 28°/28°, 28°/60°, and 60°/60°.
Two sets of tests were carried out with the three units: single-phase performance tests with
water, and evaporator performance tests with R134a and R507A, for which the exchangers
operated as refrigerant liquid over-feed evaporators. The tests with water served to provide
accurate water-side heat transfer information for the evaporator performance analysis which is
the primary purpose of this study. In the evaporator performance tests, refrigerant flow boiling
heat transfer and two-phase pressure drop data were obtained under steady conditions, over a
range of heat flux from 1.9 to 6.9 kW/m2, refrigerant mass flux from 5.6 to 31.4 (kg/m
2s),
outlet vapour quality from 0.2 to 0/95, and saturation temperatures from 5.9 to 13.0 °C which
are taken from Performance analysis of plate heat exchangers used as Refrigerant evaporators:
by jianchang huang[3]
Additional field data of thermal performance were collected on an ammonia and a R12
PHE water chiller, operating as thermo-siphon evaporators at their design working conditions.
Heat Transfer Analysis of Corrugated Plate Heat Exchanger of Different Plate Geometry: A
Review By: Jogi Nikhil G, Assist. Prof. Lawankar Shailendra[4]
Corrugated plate heat exchangers have larger heat transfer surface area and increased
turbulence level due to the corrugations. In this study, experimental heat transfer data will
obtained for single phase flow (water-to-water) configurations in a corrugated plate heat
exchanger for symmetric 45°/45°, 45°/75° chevron angle plates. The effect of variation of
chevron angles with other geometric parameter on the heat transfer coefficient will be study.
Reynold number ranging from 500 to 2500 and Prandtl number ranging from 3.5 to 6.5 will
be taken for given experiment. Based on the experimental data, a correlation will estimate for
Nusselt number as a function of Reynolds number, Prandtl number and chevron angle as said
in Design and Cost Optimization of Plate Heat Exchanger By Sreejith K, Basil Varghese,
Deepak Das, Delvin Devassy, Hari Krishnan K, Sharath G.[5]
When the application is within the pressure and temperature limits of both designs, the
selection process should focus on initial cost, maintenance requirements, and future operating
conditions. The advantages of using PHE were investigated experimentally. The main
conclusions are listed as follows by sreejith k[5]:
• A plate costs approximately Rs 3750. So the newly designed plate heat exchanger will
cost approximately
• Rs 405000 which can replace the present two heat exchangers which together cost Rs
560000.
• This leads to great reduction in space and cost without affecting the heat will transfer
efficiency.
• Initial cost is generally a function of approach temperature. Close approach temperatures
temperature crosses favour the plate and frame heat exchanger while wide temperature
approaches favour the shell and tube design.
D.V.Sai Teja and Dr Y.V.Hanumantha Rao
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• When considering the maintenance costs, the determining factor should be the properties
of fluid involve. When the fluid has a gr-eater tendency to foul, the plate and frame design
offer easier access to heat transfer surface for cleaning. In addition, because of high
turbulence, plate type heat exchangers have less of a tendency to scale or foul when
compared to a shell and tube design.
• If your application requires a high probability against leakage, the better choice is shell
and tube design. While the gasket is a weakness in the plate and frame design, the ability
to expand or reduce the thermal capacity by adding or reducing plate s is a major
advantage for the plate and frame heat exchanger. If you think the application may be
expanded in the future, a plate heat exchanger is far the easiest and the most economical
design.
In the present numerical study, the heat transfer performance and fluid flow characteristics
of various Nano fluids flowing in a counter flow PHE have been presented. The corrugated
chevron PHE has been simulated, and the 3-D temperature and velocity fields have been
obtained through numerical simulation. CFD based analysis has been used by considering
Nano fluids as homogeneous mixture. Numerical investigation of heat transfer and fluid flow
in plate heat Exchanger using Nano fluids By Arun Kumar Tiwari, Pradyumna Ghosh, Jahar
Sarkar, Harshit Dahiya , Jigar Parekh[1]
Compact heat exchangers are most widely used for heat transfer applications in industries.
Plate heat exchanger is one such compact heat exchanger, provides more area for heat transfer
between two fluids in comparison with shell and tube heat exchanger. The present work deals
with experimental heat transfer data performed on plate type heat exchanger which is used in
hydraulic cooling system in an industry. The heat exchanger used for carrying out this work
consists of thin metal welded plates of stainless steel with 0.5mm thickness; distance between
two plates is 5mm, chevron angle 60° and Counter flow arrangement.
The total heat transfer area is 161.62 m2. This consists of total 249 numbers of plates and
it is designed to withstand with 65°C temperature with a flow rate of 64751 kg/h and cold
fluid enters with a flow rate of 82366 kg/h at 35°C and leaves at 44.29°C, pressure drop is
neglected. The inlet and outlet temperatures of cold and hot fluids are been observed and with
that conditions performance evaluation is done. Based on the experimental data, a correlation
will estimate for Nusselt number as a function of Reynolds number, Prandtl number and
chevron angle and the outputs obtained are convective heat transfer coefficient, overall heat
transfer coefficient, and exchanger effectiveness. From the obtained results, graphs are drawn
to assess the performance of the Gasketed Plate heat exchanger. Heat Transfer Analysis of
Gasketed Plate Heat Exchanger: By: G.Anusha, P.S.Kishore[6]
1. Geometry:
Figure 1 CATIA model of plate heat exchanger with one plate Figure 2 After patterning to three plates
in Design modeller
Numerical Investigation of Heat Transfer and Fluid Flow in Plate Heat Exchanger With Different Types of
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Figure 3
Above Figure 1 for simulation. Figure 2
shows the model after extracting fluid domain and deleting the outer plates. Hence our model
contains one plate and two fluid domains hot fluid and cold fluid on either side of the plate
with geometry given in table: 1
2. Meshing:
1
Figure 4 M
Figure 4 shows the mesh quality as we maintained to value of skewness below 0.8 and
number of elements to 72, 47,019 Name selection have to be done to indicate the boundary
L
Width
Thickness
Diameter of Inlet/Outlet
Numerical Investigation of Heat Transfer and Fluid Flow in Plate Heat Exchanger With Different Types of
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Figure 3 After extracting fluid domain
simulation. Figure 2 model after patterning to three p
shows the model after extracting fluid domain and deleting the outer plates. Hence our model
contains one plate and two fluid domains hot fluid and cold fluid on either side of the plate
with geometry given in table: 1
Table 1 Geometry
Meshed body showing mid plate and fluid domain
Figure 4 shows the mesh quality as we maintained to value of skewness below 0.8 and
47,019 Name selection have to be done to indicate the boundary
Length 192mm
Width 74mm
Thickness 0.75mm
Diameter of Inlet/Outlet 18mm
Numerical Investigation of Heat Transfer and Fluid Flow in Plate Heat Exchanger With Different Types of
model after patterning to three pates and figure 3
shows the model after extracting fluid domain and deleting the outer plates. Hence our model
contains one plate and two fluid domains hot fluid and cold fluid on either side of the plate
eshed body showing mid plate and fluid domain
Figure 4 shows the mesh quality as we maintained to value of skewness below 0.8 and
47,019 Name selection have to be done to indicate the boundary
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conditions in fluent solver, here we have 8 named selections as two inlets and two outlets that
is for hot fluid and cold fluid respectively and four interface surfaces hot and cold surfaces of
the plate, hot and cold surfaces of fluid domains.[8]
3. NUMERICAL SIMULATION
Finite volume discretisation approach were used from fluent commercial ANSYS software
realisable k-ε model{eq. (1)& eq. (2)} were chosen after calculating the Reynolds’s Number
for used hydraulic diameter. We choose the materials according to their properties as we
required given in the table 2. Boundary conditions used are given below in the table 3 [7],[8]
�(��)�� + �
�� ���� = ��� ��� + ��
��� ����� + �� + �� − �� − �� + �� (1)
�(��)�� + �
�� ���� = ��� ��� + ��
��� ����� + ����� − ��� ����√ �+ ��� ���!��� + �� (2)
Where,
�� = �"�(#. %!, ''�() , ' = � �
� , � = √��)�) TABLE 2 Properties of materials and fluids
Material Density
kg/m^3
Specific Heat
j/kg-K
Thermal Conductivity
w/m-K
Aluminium 2719 871 202.4
Copper 8978 381 387.6
Inconel-718 8220 435 11.4
Methanol 785 2534 0.2022
Water 998.2 4182 0.6
Table 3 Boundary conditions
Boundary Type Magnitude
Hot Fluid mass flow inlet 0.2 kg/s
Cold Fluid mass flow inlet 0.2 kg/s
Hot fluid inlet temperature 368 K
Cold fluid inlet temperature 288 K
Hot/Cold fluid outlet pressure 0 Pa
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4. RESULTS AND DISCUSSION
Temperature distribution
Figure 5 Cold side temperature distribution on Cu, Al, and Inconel-718 plates
Figure 6. Hot side temperature distribution on Cu, Al, and Inconel-718 plates
Cu Al Inconel-718
plate
D.V.Sai Teja and Dr Y.V.Hanumantha Rao
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The above figure 5 and figure 6 shows the Temperature distribution on the plates Cu, Al,
and Inconel- 718 plates from cold side and hot side respectively. That there is no much
bigger difference between the temperature distribution on copper and aluminum plates. As
Copper and aluminum are good conductors of heat. Their temperature distributions on cold
side of the plate and hot side of the plate are almost same.
It is observed that very less heat is transferred from the hot fluid to cold fluid through
Inconel plate when compared to Copper and Aluminum plates. Because, Inconel has very less
thermal conductivity that is 11.14 w/m-k whereas Copper and Aluminum has 387.6 w/m-k
and 202.4 w/m-k respectively.
The Figure 7 shows the variation of temperature on Copper, Aluminium and Inconel
plates on a symmetric plane. It is observed that very less temerature variation on the Inconel
plate compared to Copper and Aluminium plates.
Figure 7 Temperature distribution on the surface of Cu, Al, Inconel plates on a symmetric plane
The Figure 8 and figure 9 shows the Temperature distribution on a vortex generated
surface[9] of Cu, Al, and Inconel-718 plate from cold fluid side and hot fluid side respectively
As the vortex surface which we generated disturb the flow as result turbulence increases the
turbulence in the flow increases the heat transfer rate from the hot fluid to cold fluid. Finally
the cold fluid gains the more heat from the hot fluid because of this vortex surface. These
vortex generated surfaces are mainly used to enhance heat transfer rate where the convective
heat transfer coefficients are relatively lesser.
Numerical Investigation of Heat Transfer and Fluid Flow in Plate Heat Exchanger With Different Types of
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Vortex Generated Surface Based Temperature Plot on Cold Side of the Plate
Figure 8 Temperature distribution on Vortex generated surface of Cu, Al and Inconel-718 plates from
cold fluid side
Vortex Generated Surface Based Temperature Plot on Hot Side of the Plate:
Figure 9 Temperature distribution on Vortex generated surface of Cu, Al and Inconel-718
plates from hot fluid side.
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Table 4 Temperature values at outlet and inlets of different materials
Boundary Copper Plate Aluminium Plate Inconel Plate
Cold Fluid Inlet 288K 288K 288K
Cold Fluid Outlet 296.328 293.879 291.582
Hot Fluid Inlet 368K 368K 368K
Hot Fluid Outlet 360.685 361.187 362.315
The above table 4 shows the temperature at the outlet of cold fluids numerically we can
understand that maximum heat transfer occurs in coper plate and temperature of outlet gained
is high for it comparing to other materials (Al, Inconel-718)for copper plate among three
because of its high thermal conductivity and low for the Inconel plate.
Whereas Aluminum plate stands in between them. Based on the cold fluid outlet
temperature we can understand that copper plate gives the more heat to cold fluid and
increases its outlet temperature.
Pressure distribution:
Figure 10 Water side pressure distribution cu, al, Inconel plates
Pressure distribution[10] contours shows the variation of pressure at different locations on
the plate. The above Figure 10 shows the pressure distribution on cold side on Aluminum,
Copper and Inconel plates respectively. It is observed that the maximum pressure at the inlet
on the aluminum plate and copper plates is 0.94 bar where as on the Inconel plate it is 1 bar
and it is dropped to very less values at the outlet on all the plates. The below figure11 shows
pressure Distribution on hot side on Copper, Aluminum and Inconel-718 respectively.
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VELOCITY DISTRIBUTION
Figure 12 Stream lines of velocity on copper, aluminium, Inconel
Figure 11 Pressure Distribution on Cu Al and Inconel plates on hot side
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Stream lines of velocity shows the magnitude of velocity at different locations on the plate
Figure 12 shows the variation of velocity on aluminum, copper and Inconel plates
respectively. It is observed that the maximum magnitude of velocity is almost equal on all the
three plates as shown in the figures.
The figures 13, 14 shows the variation of temperature along the length of the plate for hot
and cold fluid respectively. We are noticed that copper is having high thermal conductivity of
387.6 w/m-k. Because of this, the plate with copper material possess high heat transfer rate
from hot fluid to cold fluid. Whereas, the plate with Inconel-718 having less thermal
conductivity of 11.4 w/m-k material possess less heat transfer rate from hot fluid to cold fluid
While the plate with the material Aluminum having the thermal conductivity of the order
of 202.4 w/m-k. As a result the plate with Aluminum as material possess the heat transfer in
the range between the Copper plate and Inconel-718 plate.
Figure 13 Temperature distribution along the length on plate of the hot fluid side
360
361
362
363
364
365
366
367
368
369
-0.1 -0.08 -0.06 -0.04 -0.02 0 0.02 0.04 0.06 0.08 0.1 0.12
Te
mp
era
ture
, (K
)
Length along flow direction, (m)
Cu_hot_side Al_Hot_Side Inc-718_Hot_Side
Numerical Investigation of Heat Transfer and Fluid Flow in Plate Heat Exchanger With Different Types of
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Figure 14 Temperature distribution along the length on plate of the cold fluid side
5. NUMERICAL ANALYSIS
The Table 5 and Table 6 shows the Non-Dimensional numbers like Reynold’s number(Re),
Nusselt number(Nu) and Biot number(Bi) for hot fluid and Cold fluid respectively. [11].In this
case we use the Corrugated plate which promote the turbulence in both the fluids. Later we
calculate the Reynolds number (Re), Nusselt number (Nu) and Biot number (Bi) from the
following Empirical relations .The Prandtl number (pr) of both the Fluids are taken from Heat
and Mass Transfer Data Book [12]
Re =
*.+,-./0 (3)
12 = 3.66 + 5.66789:�5.5;89<= (4)
Where Graetz Number (GZ) is defined as
GZ = Re.Pr.+>? (5)
287.5
288
288.5
289
289.5
290
290.5
291
291.5
292
292.5
293
-0.1 -0.08 -0.06 -0.04 -0.02 0 0.02 0.04 0.06 0.08 0.1
Te
mp
era
ture
, (K
)
Length along the flow, (m)
Cu_Cold_Side Al_Cold_Side Inc-718_Cold_Side
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Table 5 Non- Dimensional numbers of Hot Fluid with varying Mass flow rate
S.NO
Mass flow
rate
(Kg/sec)
Velocity
(M/sec.)
Reynold’s
Number
Nusselt
Number
Heat
transfer
coefficient
(W/m2k)
Biot number
AL CU IN-718
1 0.2 0.00876 30852.7705 133.9142 141.0283 0.1337 0.0698 2.3752
2 0.3 0.01331 46279.1558 158.5286 166.9504 0.1583 0.0826 2.8117
3 0.4 0.01775 61705.5411 179.1730 188.6915 0.1789 0.0934 3.177
4 0.5 0.02219 77131.9264 198.8034 209.3648 0.1986 0.1037 3.5261
5 0.6 0.02662 92558.3117 214.0003 225.3690 0.2137 0.1116 3.7956
6 0.7 0.03106 107984.6970 227.5131 239.59979 0.2272 0.1185 4.0353
Table 6 Non-Dimensional numbers of Cold Fluid with varying Mass flow rate
S.NO
Mass
flow rate
(Kg/sec.)
Velocity
(M/sec.)
Reynold’s
Number
Nusselt
Number
Heat transfer
coefficient
(W/m2k)
Biot number
AL CU IN-718
1 0.2 0.00698 186928.2915 290.5908 908.0962 0.8614 0.4498 15.2942
2 0.3 0.01047 280392.4373 337.5273 1054.7728 1.0005 0.5224 17.7645
3 0.4 0.01396 373856.583 374.5660 1170.5187 1.1103 0.5798 19.7139
4 0.5 0.01745 467320.7288 405.6651 1267.7034 1.2025 0.6279 21.3507
5 0.6 0.02094 560784.8745 432.7382 1352.3068 1.2828 0.6698 22.7756
6 0.7 0.02443 654249.0203 456.8725 1427.7265 1.3543 0.7072 24.0459
Finally we calculate the Biot number which relate the Thermal Conductivity of Metal that
involved in Heat transfer
Bi =>?
@ABCDEGCHI, (6)
AS we know that Biot number is defined as the ratio of the internal conductive resistance
offered by the Metal to the External Convective resistance offered by the fluid. Hence the
Value of Biot number represents the resistance to Heat conduction indirectly as we keeping
the same fluids properties throughout the process. The plate with Inconel-718 as material
offers high Biot number and increases with mass flow rate. As Biot number is high then
resistance to conduct heat through the plate is also high so the heat transfer rate through the
Inconel-718 plate is very less as compared to other two metal plates .While the values of Biot
number for the Copper Plate are very small, so the heat transfer rate through the Copper plate
is very high and gives high performance in heat transfer than the two metal plates. The
Aluminum plate offers the Biot number values in between the Copper and Inconel-718 Plates
and it stands in between them in heat transfer rate also.
The following Figures 15 and 16 shows the Variation of Biot number with Mass flow rate
for Hot and Cold Fluids respectively. The Biot number variation with mass flow rate is very
high for the Inconel-718 Plate as Compared to Aluminum and Copper Plates.
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Hence from the above numerical calculations we proved that the Copper as plate Material
Enhances the Heat Transfer rate and it gives better Performance than the Al and Inconel-718
plates. We proved that Copper plate Possess the high heat transfer rate through CFD as well
as through numerical Calculations than Al and Inconel-718 plates.
Figure 15 Variation of Biot Number with Mass flow rate of Hot Fluid
Figure 16 Variation of Biot Number with mass flow Rate of Cold Fluid
0
5
10
15
20
25
30
0.2 0.3 0.4 0.5 0.6 0.7
ma
ss f
low
ra
te o
f co
ld f
luid
Biot number
aluminium copper inconel-718
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
0.2 0.3 0.4 0.5 0.6 0.7
Bio
t n
um
be
r
Mass flow rate (kg/sec.)
aluminium copper inconel-718
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6. EFFECTIVENESS CALCULATION
Effectiveness of the Heat Exchanger is the ratio between actual Heat Transfer rate taking
place between hot and cold fluids in the Heat Exchanger and the Maximum possible heat
transfer rate between them. It indicates the performance of Heat Exchanger [13], [14]
∈= .KLMNOPQNLRSNTUVQSSNLQWNXY*M*Z[UUY\OQPQNLRSNTUVQSSNLQ (7)
Qactual = Actual Heat Transfer rate = Rate of Enthalpy change of either Fluids
= mh
.Cph(Thi-The) = m
.Cpc(Tce-Tci) (8)
Qmax = Maximum possible Heat Transfer Rate
= (Thi –Tci)(m.Cp) small (9)
Where m.Cp small is the smaller Heat Capacity rate between hot and cold fluids. Heat
capacity rate of Methanol is smaller than Water in this case.
Effectiveness of Heat Exchanger with Copper plate is given by(7)
∈= (368 − 360.685)(368 − 288)
∈=0.09143
Effectiveness of Heat Exchanger with Aluminum plate is given by
∈= (368 − 361.187)(368 − 288)
∈=0.08516
Effectiveness of Heat Exchanger with Inconel-718 plate is given by
∈= (368 − 361.187)(368 − 288)
∈=0.07106
From all the above calculations we found that the Effectiveness of the Heat Exchanger
with Copper as plate material is higher than the Al and Inconel-718.Hence the Performance of
Copper Plate Heat Exchanger is better than that of Al and Inconel-718 Plate Heat Exchangers
7. CONCLUSION
In this work Heat Exchanger concept was studied with Plate Heat Exchanger keeping
unchanged hot and cold fluids for different types of Plate metal configuration, one model was
made using CATIA and simulation done with help of ANSYS fluent with three different plate
materials. Results were observed and verified with related papers. The corrugation pattern of
the plate develops turbulence of fluid. Plate with Inconel-718 material performing poor
because of its low thermal conductivity and high Biot Number and inversely plate with copper
material performing well, obviously because of its high thermal conductivity and low Biot
number. Aluminum stands in between copper and Inconel-718 in terms of Thermal
Conductivity as well as in Biot number. The Effectiveness of Heat Exchanger with Copper
Plate is more than that of Aluminum and Inconel-718 plates. As a result Copper Plate gives
better performance than Al and Inconel-718 metal plates
Numerical Investigation of Heat Transfer and Fluid Flow in Plate Heat Exchanger With Different Types of
Plate Materials
http://www.iaeme.com/IJMET/index.asp 636 [email protected]
Hence, Among Copper, Aluminum and Inconel-718, Copper is better in all aspects.Finally
we can conclude from this work that using of plate material which has more thermal
conductivity and less Biot number Possess more heat transfer.
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http://www.iaeme.com/IJMET/index.asp 637 [email protected]
Gd − Turbulenceduetobuoyancy
r:s − 1.44
ru − 1.9
Nomenclature
PHE- Plate heat exchanger
D -Diameter of inlet/outlet
Cv - Control Volume
R - Rutherford’s Constant
S -Modulus of the mean rate-of-strain tensor
µt - turbulent or eddy viscosity
u, v & w - velocity components in the x, y and z directions.
wUi/wxj&wuj/wxi – Velocity gradients.
Sij - Body forces
xy- Production of kinetic energy
ε - Dissipation rate
T – Temperature
p - Static pressure
t – Time, ρ − density
k - Thermal conductivity, W/m
IN-718 – Inconel-718 alloy
Cph,Cpc – specific heat of hot and cold fluids respectively
mh
. , mc
.-mass flow rate of hot and cold fluids (kg/sec.)
Tce, Tci – temperature of cold fluid at exit and entry respectively
The, Thi– temperature of hot fluid at exit and entry respectively
∈- Effectiveness
de = Equivalent Diameter =2b in meters
N= number of inter plate channels
Ac = channel flow cross section area in m2
µ = Dynamic Viscosity in Pa-Sec
h = Heat Transfer coefficient in W/m2k
L = Length of the Plate in meters