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Pag. 17
Thermo-hydraulic design of a multi-tube heat exchanger for methanol
heating.
Diseño térmico-hidráulico de un intercambiador de calor multi-tubo para el calentamiento de
metanol.
Amaury Pérez Sánchez
1
*; Zamira María Sarduy Rodríguez
2
; Arlenis Cristina Alfaro Martínez
3
; Elizabeth Ranero González
4
; Eddy Javier Pérez Sánchez
5
Received: 15/12/2024 – Accepted: 15/03/2025 – Published: 01/07/2025
Research
Articles
X
Review
Articles
Essay Articles
* Author for correspondence.
Abstract.
A type of heat exchanger that has gained adequate attention owing to its simplicity, robustness and extensive variety of applications is the multi-tube heat exchanger.
In the present work a multi-tube heat exchanger was designed form the thermo-hydraulic point of view, in order to heat a methanol stream to 60 ºC using water
condensate as the heat transfer agent. To design this equipment, a classical, well known calculation methodology was employed, where several important design
parameters were calculated such as the overall heat transfer coefficient (575.17 W/m
2
.K), the required heat exchange area (2.025 m
2
) and the Log Mean Temperature
Difference (38.02 ºC). The calculated pressure drop values of the methanol and water streams were 3,257.66 Pa and 752.88 Pa, respectively, which are lower than
the maximum limits set by the heat exchange service for both streams. The designed multi-tube heat exchanger will present a total length of 5.76 m.
Keywords.
Heat exchange area, multi-tube heat exchanger, pressure drop, tube length.
Resumen.
Un tipo de intercambiador de calor que ha ganado adecuada atención debido a su simplicidad, robustez y extensa variedad de aplicaciones es el intercambiador de
calor de multi-tubo. En el presente trabajo, un intercambiador de calor de multi-tubo fue diseñado desde el punto de vista térmico-hidráulico, con el fin de calentar
una corriente de metanol hasta 60 ºC usando agua condensada como agente de transferencia de calor. Para diseñar este equipo, se empleó una metodología de
cálculo clásica y bien conocida, donde varios parámetros de diseño importantes fueron calculados tales como el coeficiente global de transferencia de calor (575,17
W/m
2
.K), el área de transferencia de calor requerida (2,025 m
2
) y la Diferencia de Temperatura Media Logarítmica (38,02 ºC). Los valores de caída de presión
calculados de las corrientes de metanol y agua fueron 3 257,66 Pa y 752,88 Pa, respectivamente, los cuales están por debajo de los límites máximos fijados por el
servicio de intercambio de calor para ambas corrientes. El intercambiador de calor multi-tubos diseñado presentará una longitud total de 5,76 m.
Palabras clave.
Área de intercambio de calor, intercambiador de calor multi-tubo, caída de presión, longitud del tubo
1. Introduction
Heat exchangers are thermal apparatuses aimed for the
efficient heat exchange between two fluids, whether the
fluids are in direct contact, mixed, or separated by a thin
solid wall (unmixed). They are proposed in a range of sizes,
shapes, and construction types depending on the industrial
purpose. The performance of heat exchangers can be
upgraded by suitable design and establishing optimal
operating specifications. Therefore, the continued
improvement of different design aspects and the
performance characteristics of heat exchangers is the main
target of both researchers and manufacturers who are
working in this field [1].
1
Faculty of Applied Sciences; University of Camagüey; amaury.perez84@gmail,com; https://orcid.org/0000-0002-0819-6760, Camagüey,
Cuba.
2
University of Camagüey; Faculty of Applied Sciences; zamira.sarduy@reduc.edu.cu; https://orcid.org/0000-0003-1428-3809, Camagüey;
Cuba.
3
Center of Genetic Engineering and Biotechnology of Camagüey; arlenis.alfaro@cigb.edu.cu; https://orcid.org/0000-0003-2975-6867,
Camagüey, Cuba.
4
Faculty of Applied Sciences; University of Camagüey; eliza.eddy2202@gmail.com; https://orcid.org/0000-0001-9755-0276, Camagüey,
Cuba.
5
Commercial Department; Company of Automotive Services S.A.; eddyjavierpsanchez@gmail.com; https://orcid.org/0000-0003-4481-1262,
Ciego de Ávila, Cuba.
Heat exchanger thermal design heavily rely on physical
properties for obtaining heat transfer coefficients and
therefore performing design calculations such as heat
exchange area and overall heat transfer coefficients [2].
Among the common tubular heat exchanger used today in
many industries are the multi-tube heat exchangers (MTHE)
which comprise several smaller diameter pipes aligned in
parallel within a larger diameter outer shell (Figure 1). In
welded designs, the inner tubes and shell are welded to the
tube sheets [3].
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Pag. 18
Fig. 1. An overview of a multi-tube heat exchanger.
Source: [3].
Appropriate for heating, cooling, sterilization and thermal
treatment, MTHE can process a wide variety of liquids
(dairy, juices, sauces, beverages, processed food) from low
viscosities up to medium/high viscosities, depending on the
purpose. They can also be used for products with particles
when fitted with a conical tube-sheet [3].
Due to their assembly with distinctive configurations of
inner tubes bundled inside an outer shell, MTHE generate a
significant heat exchange area in a reasonably small
volumetric space. This configuration makes this heat
exchanger valuable for handling an extensive range of
flowrates. Among the main features that these types of heat
exchanger present are [3]:
1) The use of thermal expansion bellows to absorb
difference of expansion.
2) Conical tube sheet for liquids containing particles.
3) Baffles are commonly installed for mechanical strength
and better heat transfer on the shell side.
4) Product side can be scrutinized by eliminating bends
between units. All inner tubes are observable.
5) Low cost, straightforward maintenance with the only
requisite of periodically replacing gaskets on
connections.
According to [4] these units are usually constructed by
specialized companies, and there are several patent-
protected closure systems. They can be an economical
solution in cases where the flowrates are relatively small
and it is required to apply a countercurrent configuration.
They are restricted to a few inner tubes because for higher
sizes this type of assembly becomes challenging. They are
not a competitive solution against the shell and tube heat
exchangers (STHE), although they are cheaper than STHE
[5], and are limited to applications where the required heat
transfer area is less than 10 or 15 m
2
[4].
Efficient and accurate thermal analysis of MTHE provides
a basis for successful design [6]. The primary attention of
MTHE design is the efficiency of heat dissipation by solid
conduction and forced flow convection. A good MTHE
should have an optimum multi-tube configuration to
dissipate as much heat as possible [6].
There are few studies reported in the open published
literature where a multi-tube heat exchanger is designed or
sized. According to this, in [7] a co-axial multi-tube heat
exchanger (CMTHE) is proposed and integrated with a 50
kW geothermal Organic Rankine Cycle (ORC), in order to
perform tow field tests to examine the response of the ORC
system subject to changes applied to the CMTHE. In this
study the working fluid in the tube-side of the heat
exchanger is pure water with a flowrate of 13 tons per hour,
while in the shell side the working fluid is geothermal hot
water ( 120 ºC). The CMTHE used in this work has a total
length of 11 m, an effective heat transfer area of 18.6 m
2
,
and the internal and external diameter of the tubes are 10.7
mm and 12.7 mm, respectively. Other authors [1]
investigated the influence of several operating parameters
on the performance of concentric finned tube and bare
multi-tube hairpin heat exchangers. A computer program
was written and developed to carry out thermo-hydraulic
computations using the MATLAB. The developed
MATLAB code was then verified for reliability and
precision against some of the existing and acceptable
designs of single-finned tube and bare multi-tube hairpin
heat exchangers. The existing counter flow bare multi-tube
heat exchanger evaluated in this study used fresh water on
the shell side, and oily water on the tube side with a mass
flowrate of 6,622 kg/h for both streams; the internal and
external diameters of the tubes are 17.95 mm and 22.21 mm,
respectively; the number of internal tubes is 7; the inlet
temperatures of the tube side fluid (oily water) and the shell
side fluid (fresh water) were 247 ºC and 80 ºC, respectively;
and the total length of the heat exchanger is 60.96 m.
Finally, the allowable pressure drops for both fluid streams
were 137,895.15 Pa, while the actual pressure drop of the
oily water in the tube side was 22,063.22 Pa. Likewise, [6]
proposed a general mathematical model for the optimal
heat-transfer efficiency design of compact multi-tubular
heat exchangers using topology optimization concepts. For
optimization objectives, the multi-tubular configuration was
transformed into an equivalent cellular material distribution
within a given cross-section, which was then exemplified by
two design variables: local relative cell density and cell size.
Also, in [8] a numerical performance investigation of a
phase change material-based multi-tube heat exchanger
incorporated with two new fin configurations was carried
out, in order to enhance the heat transfer. Finally, in a
comprehensive experimental and numerical investigation,
[9] studied smooth and rectangular-finned double pipe and
multi tube heat exchangers with the prospect of presenting
the most optimum operating conditions.
Certain chemical plant erected in Cuba needs to heat a liquid
methanol stream to 60 ºC using hot water (condensate), and
for that a multi-tube heat exchanger was proposed because
the flowrates of the fluids are relatively small, there is
enough space availability and there is limitation of budget.
In this context, in the present paper a MTHE is designed
applying the methodology reported in [10], where several
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Pag. 19
important parameters are determined such as the overall
heat transfer coefficient, the required heat exchange area,
the length of the heat exchanger, and the pressure drop of
both fluids.
2. Materials and methods.
2.1. Problem statement.
It’s required to preheat 2,000 kg/h of a liquid methanol
stream from 30º C to 60 ºC using 3,000 kg/h of hot water
(condensate) available at 90 ºC. For that, a multi-tube heat
exchanger was proposed with a shell internal diameter of
72.1 mm, equipped with seven inner tubes with an internal
and external diameter of 14 and 16 mm, respectively. The
pressure drops for the methanol and water stream must not
exceed 3,500 and 1,000 Pa, respectively. The material of the
tubes is carbon steel; the fluids will flow in a countercurrent
arrangement inside the heat exchanger, while the fouling
factors for methanol and water are 0.000352 and 0.000088
K.m
2
/W, respectively [11].
According to suggestions reported by [12], the cold fluid
(methanol) will be located on the tube side, while the hot
fluid (water) will be located on the shell side. The internal
diameters of the nozzles in the tube side and shell side are
32 mm and 50 mm, respectively, and the wall thickness of
the tubes is 2 mm. It’s necessary to know the tube length
required by this multitube heat exchanger, as well as the
pressure drops of both streams, for the requested heat
transfer service. The calculation methodology proposed by
[10] should be employed in this work to design the MTHE.
2.2. Calculation of the tube length.
Step 1. Definition of the initial data available:
• Methanol mass flowrate (
).
• Water mass flowrate (
).
• Inlet temperature of methanol (
).
• Outlet temperature of methanol (
).
• Inlet temperature of water (
).
• Internal diameter of shell (
).
• Internal diameter of tubes (
).
• External diameter of tubes (
).
• Internal diameter of the tube side nozzle (
).
• Internal diameter of the shell side nozzle (
).
• Thermal conductivity of tube material (carbon steel)
(
).
• Tube wall thickness (
).
• Fouling factor of methanol (
).
• Fouling factor of water (
).
• Number of internal tubes ().
• Maximum allowable pressure drop for methanol
[
].
• Maximum allowable pressure drop for water [
].
Step 2. Average temperature of methanol (
):
(1)
Step 3. Physical parameters of methanol at the average
temperature determined in step 1:
The following parameters must be defined for the methanol
at the average temperature:
• Density (
) [kg/m
3
].
• Viscosity (
) [Pa.s].
• Heat capacity (
) [J/kg.K].
• Thermal conductivity (
) [W/m.K].
Step 4. Heat duty ():
(2)
Step 5. Heat capacity of water (
) at the inlet water
temperature (
).
Step 6. Outlet temperature of water (
):
(3)
Step 7. Average temperature of water (
):
(4)
Step 8. Physical parameters of water at the average
temperature determined in step 6:
The following parameters must be defined for the water at
its average temperature:
• Density (
) [kg/m
3
].
• Viscosity (
) [Pa.s].
• Thermal conductivity (
) [W/m.K].
Step 9. Cross section area of tube (
):
(5)
Step 10. Velocity of methanol on the tube-side (
):
(6)
Step 11. Reynolds number of methanol (
):
(7)
Step 12. Prandtl number of methanol (
):
(8)
Step 13. Nusselt number of methanol (
):
As stated by [10], the Nusselt number depends on the value
of the Reynolds number of the fluid inside the heat
exchanger. Accordingly:
• Laminar region (
2,300):
(9)
• Intermediate region (2,300 <
< 8,000):
(10)
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Pag. 20
• Turbulent region (
8,000):
(11)
Step 14. Convective heat transfer coefficient for methanol
(
):
(12)
Step 15. Convective heat transfer coefficient for methanol
based on the tube outer surface area (
):
(13)
Step 16. Flow cross-section in the shell (
shell
a
):
(14)
Step 17. Velocity of water on the shell (
h
v
):
(15)
Step 18. Hydraulic diameter for heat exchange (
h
d
):
(16)
Step 19. Reynolds number of water (
):
(17)
Step 20. Prandtl number of water (
):
(18)
Step 21. Nusselt number of water (
):
• Laminar region (
2,300):
(19)
• Intermediate region (2,300 <
< 8,000):
(20)
• Turbulent region (
8,000):
(21)
Step 22. Convective heat transfer coefficient for water
(
):
(22)
Step 23. Overall heat transfer coefficient ():
(23)
Step 24. Log Mean Temperature Difference ():
• For a countercurrent arrangement:
(24)
Step 25. Required heat exchange area (
):
(25)
Step 26. Length of the heat exchanger (
L
):
(26)
2.3. Calculation of the pressure drops.
Step 27. Cross section area of tube-side nozzle (
):
(27)
Step 28. Flow velocity of methanol in tube-side nozzle
(
):
(28)
Step 29. Nozzle pressure drop of methanol in the tube side
(
):
(29)
Step 30. Friction factor of methanol (
):
(30)
Step 31. Frictional pressure drop of methanol in the tube
side (
):
(31)
Step 32. Total pressure drop of methanol in the tube side
(
):
(32)
Step 33. Cross section area of the shell-side nozzle (
):
(33)
Step 34. Flow velocity of water in the shell-side nozzle
(
):
(34)
Step 35. Nozzle pressure drop of water in the shell side
(
):
(35)
Step 36. Hydraulic diameter for the pressure drop (
):´
(36)
Step 37. Reynolds number of water for pressure drop
(
):
(37)
Step 38. Friction factor of water (
):
(38)
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Pag. 21
Step 39. Frictional pressure drop of water in the shell side
(
):
(39)
Step 40. Total pressure drop of water in the shell side (
):
(40)
3. Results.
The steps followed to determine the required tube length
and the pressure drop of both streams, among other
important parameters, are presented next, in order to design
the multitube heat exchanger from the thermo-hydraulic
point of view.
3.1. Tube length.
Step 1. Definition of the initial data available:
• Methanol mass flowrate (
): 2,000 kg/h.
• Water mass flowrate (
): 3,000 kg/h.
• Inlet temperature of methanol (
): 30 ºC.
• Outlet temperature of methanol (
): 60 ºC.
• Inlet temperature of water (
): 90 ºC.
• Internal diameter of shell (
): 0.0721 m.
• Internal diameter of tubes (
): 0.014 m.
• External diameter of tubes (
): 0.016 m.
• Internal diameter of the tube side nozzle (
): 0.032 m.
• Internal diameter of the shell side nozzle (
): 0.050
m.
• Thermal conductivity of carbon steel (
): 43 W/m.K
[11].
• Tube wall thickness (
): 0.002 m.
• Fouling factor of methanol (
): 0.000352 K.m
2
/W
[11].
• Fouling factor of water (
): 0.000088 K.m
2
/W [11].
• Number of tubes (): 7.
• Maximum allowable pressure drop for methanol
[
]: 3,500 Pa.
• Maximum allowable pressure drop for water [
]:
1,000 Pa.
Step 2. Average temperature of methanol (
):
(1)
Step 3. Physical parameters of methanol at the average
temperature determined in step 1:
According to [13], the methanol has the values presented
next for the requested physical parameters:
• Density (
) = 770.12 kg/m3.
• Viscosity (
) = 0.000423 Pa.s.
• Heat capacity (
) = 2,657.53 J/kg.K.
• Thermal conductivity (
) = 0.1943 W/m.K.
Step 4. Heat duty ():
(2)
Step 5. Heat capacity of water (
) at the inlet water
temperature (
).
As reported by [13], the heat capacity of water at 90 ºC is
4,205.21 J/kg.K.
Step 6. Outlet temperature of water (
2
T
):
(3)
Step 7. Average temperature of water (
T
):
(4)
Step 8. Physical parameters of water at the average
temperature determined in step 6:
Consistent with [14], the water presents the values of the
physical parameters presented next at the average
temperature of 83.68 ºC.
• Density (
) = 969.46 kg/m
3
.
• Viscosity (
) = 0.000339 Pa.s.
• Thermal conductivity (
) = 0.6721 W/m.K.
Table 1 presents the values of the parameters calculated in
steps 9-26.
Table 1. Results of the parameters calculated in steps 9-26.
Step
Parameter
Symbol
Value
Units
9
Cross section
area of tube
0.001077
m
2
10
Velocity of
methanol on
the tube-side
0.670
m/s
11
Reynolds
number of
methanol
1
17,077.36
-
12
Prandtl
number of
methanol
5.78
-
13
Nusselt
number of
methanol
2
99.56
-
14
Convective
heat transfer
1,381.75
W/m
2
.K
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Pag. 22
coefficient for
methanol
15
Convective
heat transfer
coefficient for
methanol
based on the
tube outer
surface area
1,209.03
W/m
2
.K
16
Flow cross-
section in the
shell
0.00267
m
2
17
Velocity of
water on the
shell
0.322
m/s
18
Hydraulic
diameter for
heat exchange
0.0304
m
19
Reynolds
number of
water
3
27,993.66
-
20
Prandtl
number of
water
2.12
-
21
Nusselt
number of
water
4
106.43
-
22
Convective
heat transfer
coefficient for
water
2,353.01
W/m
2
.K
23
Overall heat
transfer
coefficient
575.17
W/m
2
.K
24
Log Mean
Temperature
Difference
38.02
ºC
25
Required heat
exchange area
2.025
m
2
26
Length of the
heat
exchanger
5.76
m
1
Since
8,000, the methanol will flow under turbulent
regime in the heat exchanger.
2
Since
8,000, the equation employed to determine the
Nusselt number of methanol was number (11).
3
Since
8,000, the water will flow under turbulent
regime in the heat exchanger.
4
Since
8,000, the equation (21) was employed to
determine the Nusselt number of water.
Source: Own elaboration.
3.2. Pressure drops.
Table 2 shows the results of the parameters calculated in
steps 27-40.
Table 2. Results of the parameters calculated in steps 27-40.
Step
Parameter
Symbol
Value
Units
27
Cross section
area of the tube-
side nozzle
0.00080
m
2
28
Flow velocity of
methanol in the
tube-side nozzle
0.902
m/s
29
Nozzle pressure
drop of
methanol in the
tube side
469.93
Pa
30
Friction factor
of methanol
0.0392
-
31
Frictional
pressure drop of
methanol in the
tube side
2,787.73
Pa
32
Total pressure
drop of
methanol in the
tube side
3,257.66
Pa
33
Cross section
area of the shell-
side nozzle
0.00196
m
2
34
Flow velocity of
water in the
shell-side nozzle
0.438
m/s
35
Nozzle pressure
drop of water in
the shell side
139.49
Pa
36
Hydraulic
diameter for the
pressure drop
0.0185
m
37
Reynolds
number of water
for pressure
drop
17,035.61
-
38
Friction factor
of water
0.0392
-
39
Frictional
pressure drop of
water in the
shell side
613.39
Pa
40
Total pressure
drop of water in
the shell side
752.88
Pa
Source: Own elaboration.
4. Discussion.
According to the results shown on Table 1, the velocity of
methanol on the tube side was 0.670 m/s, which is 2.08
times higher than the velocity of water on the shell; this is
due to the lowest value that the density of methanol (770.12
kg/m
3
) and the cross section area of tube (0.001077 m
2
)
present with respect to the density of water (969.46 kg/m
3
)
and the flow cross-section in the shell (0.00267 m
2
).
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Pag. 23
The Reynolds number of water (27,993.66) is 1.64 times
higher than the Reynolds number of methanol (17,077.36),
which is due to the highest value that present the density of
water (969.46 kg/m
3
) and the hydraulic diameter for heat
exchange (0.0304), and the lowest value of the viscosity of
water (0.000339 Pa.s) with respect to the values of the
density of methanol (770.12 kg/m
3
), internal diameter of
tube (0.014 m) and viscosity of methanol (0.000423 Pa.s).
It’s worth noting that both streams flow under turbulent
regime since both Reynolds number are above 8,000 [10].
The convective heat transfer coefficient of water (2,353.01
W/m
2
.K) is 1.70 times higher than the convective heat
transfer coefficient for methanol (1,381.75 W/m
2
.K) mostly
because the Nusselt number (106.43) and the thermal
conductivity (0.6721 W/m.K) of water are higher than the
Nusselt number (99.56) and the thermal conductivity
(0.1943 W/m.K) of methanol.
The heat duty was of 44,292.17 W, while the calculated
outlet temperature of water was 77.36 ºC. The value of the
overall heat transfer coefficient was 575.17 W/m
2
.K, which
agrees with the values reported by [4] and [11], while the
Log Mean Temperature Difference was 38.02 ºC. The
designed MTHE will need a heat exchange area of 2.025
m
2
, which corresponds to the values reported by [4] for this
type of heat exchanger, thus requiring a total length of 5.76
m, which can be considered adequate [3]. In [10], a MTHE
was designed and the results of heat exchange area and the
total tube length were 1.01 m
2
and 2.90 m, respectively.
The nozzle pressure drop of methanol in the tube side
(469.93 Pa) is 3.37 times higher than nozzle pressure drop
of water in the shell side (139.49 Pa) which is due to the fact
that the value of the flow velocity of methanol in the tube-
side nozzle (0.902 m/s) almost double the flow velocity of
water in the shell-side nozzle (0.438 m/s). This occurred
because the internal diameter of the tube side nozzle (0.032
m) is lower than the internal diameter of the shell side
nozzle (0.050 m), thus resulting in a lower cross section area
of the tube-side nozzle (0.00080 m
2
) with respect to the
cross section area of the shell-side nozzle (0.00196 m
2
),
therefore influencing in the higher value obtained for the
flow velocity of methanol in the tube-side nozzle with
respect to the value of the flow velocity of water in the shell-
side nozzle. On the other hand, the frictional pressure drop
of methanol in the tube side (2,787.73 Pa) is 4.54 times
higher than the frictional pressure drop of water in the shell
side (613.39 Pa), which is because the velocity of methanol
on the tube-side (0.670 m/s) is higher and the internal
diameter of tubes (0.014 m) is lower than the velocity of
water on the shell (0.322 m) and the hydraulic diameter for
the pressure drop (0.0185 m), respectively. It’s worth
mentioning that the value of the friction factor of methanol
is equal to the value of the friction factor of water, that is,
both have a value of 0.0392, which is an inquiring result.
The above discussion explains why the total pressure drop
of methanol in the tube side (3,257.66 Pa) is 4.32 times
higher than the total pressure drop of water in the shell side
(752.88 Pa), that is, because both the nozzle pressure drop
of methanol in the tube side and the frictional pressure drop
of methanol in the tube side are higher in value than the
nozzle pressure drop of water in the shell side and the
frictional pressure drop of water in the shell side,
respectively. This result agrees with that reported by [10].
Figure 2 displays the schematics of the designed MTHE,
with its main design parameters and the numerical
information of both streams.
Fig. 2. Schematics of the designed MTHE.
Source: Own elaboration.
5. Conclusions.
A multi-tube heat exchanger was designed from the thermo-
hydraulic point of view, in order to heat a methanol stream
to 60 ºC using water condensate at 90 ºC. The calculation
methodology employed in this study, in order to design the
MTHE, was that reported by [10]. Several important design
parameters were determined such as the Log Mean
Temperature Difference (38.02 ºC), the overall heat transfer
coefficient (575.17 W/m
2
.K), the required heat exchange
area (2.025 m
2
), as well as the Reynolds, Prandtl and
Nusselt numbers and the convective heat transfer
coefficients for both fluids. The pressure drop of both
streams were also calculated, whose values are below the
maximum limits set by the heat exchange service. The
designed multi-tube heat exchanger will present a total
length of 5.76 m.
6.- Author Contributions.
1. Conceptualization: Amaury Pérez Sánchez.
2. Data curation: Zamira María Sarduy Rodríguez.
3. Formal Analysis: Amaury Pérez Sánchez, Arlenis
Cristina Alfaro Martínez.
4. Acquisition of funds: Not applicable.
5. Research: Amaury Pérez Sánchez, Arlenis Cristina
Alfaro Martínez, Zamira María Sarduy Rodríguez.
6. Methodology: Amaury Pérez Sánchez, Elizabeth
Ranero González.
7. Project management: Not applicable.
8. Resources: Not applicable.
9. Software: Not applicable.
University of
Guayaquil
INQUIDE
Chemical Engineering and Development
https://revistas.ug.edu.ec/index.php/iqd
e-ISSN: 3028-8533 / INQUIDE / Vol. 07 / Nº 02
Faculty of
Chemical engineering
Chemical Engineering and Development
University of Guayaquil | Faculty of Chemical Engineering | Tel. +593 4229 2949 | Guayaquil – Ecuador
https://revistas.ug.edu.ec/index.php/iqd
Email: inquide@ug.edu.ec | francisco.duquea@ug.edu.ec
Pag. 24
10. Supervision: Amaury Pérez Sánchez.
11. Validation: Amaury Pérez Sánchez, Eddy Javier Pérez
Sánchez.
12. Visualization: Not applicable.
13. Writing – original draft: Elizabeth Ranero González,
Eddy Javier Pérez Sánchez.
14. Writing - revision y editing: Amaury Pérez Sánchez.
7.- References.
[1] Ballil and S. Jolgam, "Analysis and Performance Evaluation of
Counter Flow Hairpin Heat Exchangers," American Academic
Scientific Research Journal for Engineering, Technology, and
Sciences, vol. 85, no. 1, pp. 170-188, 2022.
https://asrjetsjournal.org/index.php/American_Scientific_Journal/art
icle/view/7324
[2] D. D. Clarke, C. R. Vasquez, W. B. Whiting, and M. Greiner,
"Sensitivity and uncertainty analysis of heat-exchanger designs to
physical properties estimation," Applied Thermal Engineering, vol.
21, pp. 993-1017, 2001. https://doi.org/10.1016/S1359-
4311(00)00101-0
[3] SPX FLOW, "ParaTube MultiTube Heat Exchangers - Welded
Design for Sanitary Applications," ed. North Carolina, USA: SPX
FLOW, Inc., 2019. https://www.spxflow.com/assets/original/apv-he-
multitube-flr-us.pdf
[4] E. Cao, Heat transfer in process engineering. New York, USA: The
McGraw-Hill Companies, Inc., 2010.
https://www.accessengineeringlibrary.com/content/book/978007162
4084
[5] R. Sinnott and G. Towler, Chemical Engineering Design, 6th ed.
Oxford, United Kingdom: Butterworth-Heinemann, 2020.
https://doi.org/10.1016/C2017-0-01555-0
[6] Wang, G. D. Cheng, and L. Jiang, "Design of multi-tubular heat
exchangers for optimum efficiency of heat dissipation," Engineering
Optimization, vol. 40, no. 8, pp. 767-788, 2008.
http://dx.doi.org/10.1080/03052150802054027
[7] J. C. Hsieh, Y. R. Lee, T. R. Guo, L. W. Liu, P. Y. Cheng, and C. C.
Wang, "A Co-axial multi-tube heat exchanger applicable for a
Geothermal ORC power plant," Energy Procedia, vol. 61, pp. 874-
877, 2014. https://doi.org/ 10.1016/j.egypro.2014.11.985
[8] Dandotiya and N. D. Banker, "Numerical investigation of heat
transfer enhancement in a multitube thermal energy storage heat
exchanger using fins," Numerical Heat Transfer, Part A:
Applications, vol. 72, no. 5, pp. 389-400, 2017.
http://dx.doi.org/10.1080/10407782.2017.1376976
[9] J. Taborek, "Double-Pipe and Multitube Heat Exchangers with Plain
and Longitudinal Finned Tubes," Heat Transfer Engineering, vol. 18,
no. 2, pp. 34-45, 1997.
http://dx.doi.org/10.1080/01457639708939894
[10] M. Nitsche and R. O. Gbadamosi, Heat Exchanger Design Guide.
Oxford, UK: Butterworth Heinemann, 2016.
https://doi.org/10.1016/C2014-0-04971-4
[11] S. Kakaç, H. Liu, and A. Pramuanjaroenkij, Heat Exchangers.
Selection, Rating and Thermal Design, 3rd ed. Boca Raton, USA:
CRC Press, 2012. https://doi.org/10.1201/b11784
[12] R. K. Sinnott, Chemical Engineering Design, 4th ed. Oxford, UK:
Elsevier Butterworth-Heinemann, 2005.
[13] W. Green and M. Z. Southard, Perry's Chemical Engineers'
Handbook, 9th ed. New York, USA: McGraw-Hill Education, 2019.
[14] ChemicaLogic, "Thermodynamic and Transport Properties of Water
and Steam," Version 2.0 Burlington, USA: ChemicaLogic
Corporation, 2003.
Nomenclature
Cross section area of the shell-
side nozzle
m
2
Cross section area of the tube-
side nozzle
m
2
Flow cross-section in the shell
m
2
Cross section area of tube
m
2
Required heat exchange area
m
2
Heat capacity
J/kg.K
External diameter of tubes
m
Hydraulic diameter for heat
exchange
m
Hydraulic diameter for the
pressure drop
m
Internal diameter of tubes
m
Internal diameter of the tube side
nozzle
m
Internal diameter of shell
m
External diameter of the shell
side nozzle
m
Tube wall thickness
m
Friction factor
-
Convective heat transfer
coefficient
W/m
2
.K
Convective heat transfer
coefficient based on the tube
outer surface area
Thermal conductivity
W/m.K
Thermal conductivity of the tube
material (carbon steel)
W/m.K
Length of the heat exchanger
Log Mean Temperature
Difference
ºC
Mass flowrate
kg/h
Number of tubes
-
Nusselt number
-
Prandtl number
-
Total pressure drop
Pa
Maximum allowable pressure
drop
Pa
Frictional pressure drop of cold
fluid in the tube side
Pa
Frictional pressure drop of hot
fluid in the shell side
Pa
Nozzle pressure drop of cold
fluid in the tube side
Pa
Nozzle pressure drop of hot fluid
in the shell side
Pa
Heat duty
W
Fouling factor
K.m
2
/W
Reynolds number
-
Reynolds number for pressure
drop
Temperature of the cold fluid
ºC
Average temperature of the cold
fluid
ºC
Temperature of the hot fluid
ºC
Average temperature of the hot
fluid
ºC
University of
Guayaquil
INQUIDE
Chemical Engineering and Development
https://revistas.ug.edu.ec/index.php/iqd
e-ISSN: 3028-8533 / INQUIDE / Vol. 07 / Nº 02
Faculty of
Chemical engineering
Chemical Engineering and Development
University of Guayaquil | Faculty of Chemical Engineering | Tel. +593 4229 2949 | Guayaquil – Ecuador
https://revistas.ug.edu.ec/index.php/iqd
Email: inquide@ug.edu.ec | francisco.duquea@ug.edu.ec
Pag. 25
Overall heat transfer coefficient
W/m
2
.K
Velocity
m/s
Flow velocity of cold fluid in the
tube-side nozzle
m/s
Flow velocity of hot fluid in the
shell-side nozzle
m/s
Greek symbols
Density
kg/m
3
Viscosity
Pa.s
Subscripts
Inlet
Outlet
Cold fluid (methanol)
Hot fluid (water)
