A TECHNICAL REPORT ON
EXPERIMENT THREE
ANALYSIS OF HEAT TRANSFER IN TUBULAR AND
SHELL-AND-TUBE HEAT EXCHANGERS
MUIBUDEEN MUIZ OPEYEMI
125/20/1/0041
CHEMICAL ENGINEERING
IN PARTIAL FULFILMENT OF THE
REQUIREMENTS FOR CHEMICAL
ENGINEERING LABORATORY II (CHE 507)
6TH FEBRUARY, 2025.
Contents
ABSTRACT ....................................................................................................................................... iii
INTRODUCTION............................................................................................................................... 1
AIMS AND OBJECTIVES......................................................................................................... 2
Aims: ........................................................................................................................................... 2
Objectives:................................................................................................................................... 3
BACKGROUND AND THEORY .............................................................................................. 3
Background ................................................................................................................................. 3
Theory ......................................................................................................................................... 4
MATERIALS AND APPARATUS ......................................................................................................... 9
Materials ...................................................................................................................................... 9
Apparatus: ................................................................................................................................... 9
METHODOLOGY ............................................................................................................................ 12
General and Operating Procedure ............................................................................................. 12
General Procedure: .................................................................................................................... 12
Operating Procedure.................................................................................................................. 13
Safety Precautions ..................................................................................................................... 14
RESULT AND DISCUSSION OF THE RESULT ................................................................................... 16
Result......................................................................................................................................... 16
Discussion of Results ................................................................................................................ 26
CONCLUSION AND RECOMMENDATION ...................................................................................... 30
Conclusion................................................................................................................................. 30
Recommendations: .................................................................................................................... 31
REFERENCES .................................................................................................................................. 33
Books......................................................................................................................................... 33
Websites .................................................................................................................................... 33
ii
ABSTRACT
This technical report details an experimental investigation into the heat transfer characteristics of
tubular and shell-and-tube heat exchangers using the WL 110 apparatus. The study focused on
evaluating the effects of flow configuration (parallel and counter flow), temperature difference, and
flow rate on heat exchanger performance. Key parameters, including heat flow (𝑄𝑚), Logarithmic
Mean Temperature Difference (LMTD), and overall heat transfer coefficient (𝐾𝑚), were measured
and calculated. Results demonstrated that the counter flow configuration exhibited superior heat
transfer performance compared to parallel flow, attributed to a higher LMTD. Increased temperature
differences and flow rates positively impacted heat transfer rates and coefficients. The experiment
successfully achieved its objectives of investigating heat transfer characteristics, comparing flow
configurations, and gaining practical experience with the WL 110 equipment and its software. This
study provides valuable insights into the operational parameters influencing heat exchanger
efficiency, highlighting the importance of flow configuration and operating conditions in optimizing
heat transfer processes.
The analysis of the experimental data revealed a clear correlation between the manipulated variables
and the heat transfer performance of the exchangers. Specifically, the calculated LMTD values for
the counter flow configuration were consistently higher, leading to increased heat flow rates. The
overall heat transfer coefficient (𝐾𝑚) demonstrated a direct relationship with the flow rate, indicating
enhanced turbulence and mixing at higher flow rates. This experiment not only validated theoretical
principles of heat transfer but also provided practical experience in utilizing industry-standard
equipment and software for data acquisition and analysis. The findings of this study can be used to
inform the design and operation of heat exchangers in various industrial applications for maximum
efficiency.
iii
INTRODUCTION
This technical report presents an experimental analysis of the behavioral patterns of tubular and
shell-and-tube heat exchangers, conducted using the WL 110 apparatus. This unit facilitates the
investigation of four distinct heat exchanger types; however, this study specifically focused on the
performance of tubular and shell-and-tube configurations. The overarching objective was to
examine the impact of flow direction and operational parameters on heat transfer efficiency.
The experimental procedure involved repeating measurements three times for both counter and
parallel flow directions, ensuring robust data collection. For the tubular heat exchanger, the flow
rate was maintained constant, while the hot water temperature was incrementally increased for
each measurement. Conversely, for the shell-and-tube heat exchanger, the hot water temperature
remained constant, and the flow rate was systematically increased. A comparative measurement
was conducted at identical flow rate and temperature values for both exchangers to facilitate a
direct performance assessment. The cold water supply, provided by the WL 110.20 unit,
maintained a consistent temperature throughout the experiment. The WL 110 software was utilized
for accurate data acquisition and calculation of key parameters, enabling a precise analysis of heat
flow dependence on flow rate and temperature.
Heat exchangers are fundamental devices for transferring heat, a critical form of energy utilized
extensively in various applications, including building heating systems and domestic hot water
supply. Heat transfer occurs through three primary mechanisms: conduction, convection, and
radiation. Conduction involves direct molecular contact, radiation utilizes electromagnetic waves,
and convection relies on fluid motion. Heat exchangers are classified based on flow direction
(parallel, counter, cross, or hybrid) and configuration (recuperative or regenerative). Recuperative
exchangers, which include direct, indirect, and special types, and regenerative exchangers, which
1
include static and dynamic types, are common. Heat exchangers are indispensable in industries
such as nuclear power, automotive, food processing, and oil and gas.
This experiment specifically examined tubular and shell-and-tube heat exchangers. Tubular heat
exchangers, known for their simplicity and scalability, allow for easy expansion through modular
additions and can operate under high temperature and pressure conditions with minimal
maintenance. However, they typically exhibit lower efficiency, around 70%. Shell-and-tube heat
exchangers, categorized by the number of fluid passes (e.g., double pass), offer high corrosion
resistance and suitability for high-pressure and high-temperature applications. They are relatively
easy to clean in case of leaks. However, they require substantial space and have limited tube cooler
capacity expansion. It is also important to note that the tube side and shell side of these exchangers
have distinct operational parameters. Corrosive or high-temperature/pressure fluids are typically
channeled through the tube side, while viscous or low-flow-rate fluids are more effectively handled
by the shell side. This study aimed to provide a comprehensive analysis of the performance
characteristics of these two heat exchanger types under controlled experimental conditions.
AIMS AND OBJECTIVES
Aims:
The aim of this experiment is to analyze the heat transfer performance of tubular and shell-andtube heat exchangers under parallel and counter flow conditions and determine the effect of
temperature and flow rate variations on heat exchanger efficiency.
2
Objectives:

To investigate the heat transfer characteristics of tubular and shell-and-tube
heat exchangers.

To compare the efficiency of parallel flow and counter flow configurations.

To measure and calculate key parameters such as:
o Heat flow (𝑄𝑚)
o Logarithmic Mean Temperature Difference (LMTD)
o Heat transfer coefficient (𝐾𝑚)
 To evaluate the effect of temperature difference and flow rate on heat exchanger
performance.
 To gain practical experience in using WL 110 heat exchanger equipment and its
software for data collection and analysis.
BACKGROUND AND THEORY
Background
Efficient heat transfer between fluids is fundamental to numerous industrial and engineering
processes. Heat exchangers are pivotal in applications ranging from power generation and
refrigeration to chemical processing and HVAC, contributing significantly to energy conservation and
process optimization. Their performance is contingent upon design, flow arrangement, and
operational parameters.
3
Tubular and shell-and-tube heat exchangers are particularly prevalent due to their versatility and
efficiency. A tubular heat exchanger, characterized by a single tube within a surrounding fluid, offers
a simple heat transfer mechanism. Conversely, the shell-and-tube design, featuring multiple tubes
within a shell, provides an expanded heat transfer surface, leading to enhanced thermal performance.
Key performance indicators for heat exchangers include heat flow (𝑄𝑚), logarithmic mean
temperature difference (LMTD), and heat transfer coefficient (𝐾𝑚). Moreover, the flow
configuration—parallel or counterflow—significantly affects efficiency. Counterflow arrangements
typically yield superior performance due to the sustained temperature gradient across the exchanger.
This experiment utilizes the WL 110 unit to analyse the heat transfer characteristics of tubular and
shell-and-tube heat exchangers. By systematically varying temperature and flow rates, the study aims
to elucidate the impact of these factors on heat exchanger performance, thereby providing practical
insights for optimizing design and operational strategies.
Theory
The performance of a heat exchanger is governed by the principles of heat transfer which include
conduction, convection, and radiation. However, in most heat exchangers, heat transfer occurs
primarily through convection and conduction. This experiment systematically compares the heat
transfer performance of heat exchangers operating in both parallel and counter flow configurations.
In parallel flow, the hot and cold fluid streams move in the same direction, while in counter flow, they
move in opposite directions.
The initial step in the analysis involves determining the mass flow rates of the hot (𝑚ℎ) and cold (𝑚𝑐)
streams using the following equations:
4
1. Mass Flow rate Calculation.
The mass flow rate of hot and cold fluids is determined using:
𝑚 ℎ = 𝜌ℎ × 𝑉 ℎ
𝑚 𝑐 = 𝜌𝑐 × 𝑉 𝑐
Where:
•
𝑚ℎ, 𝑚𝑐= mass flow rate of hot and cold fluids (kg/s)
•
𝜌ℎ, 𝜌𝑐= density of hot and cold fluids (kg/m³)
•
𝑉ℎ, 𝑉𝑐= volumetric flow rate (m³/s)
The density of fluids is found using:
𝜌ℎ = 1010 − 0.47 × 𝑇ℎ
𝜌𝑐 = 1010 − 0.47 × 𝑇𝑐
Where 𝑇ℎ and 𝑇𝑐 are the average inlet and outlet temperatures of hot and cold water,
respectively.
2. Heat Flow Calculation
5
The heat transferred by hot and cold fluids is calculated as:
𝑄ℎ = 𝐶𝑝ℎ × 𝑚ℎ × (𝑇ℎ,𝑖𝑛 − 𝑇ℎ,𝑜𝑢𝑡)
𝑄𝑐 = 𝐶𝑝ℎ × 𝑚𝑐 × (𝑇𝑐,𝑖𝑛 − 𝑇𝑐,𝑜𝑢𝑡)
Where:
o
heat flow of hot and cold fluids (kW) o
specific heat capacity (J/kg·K)
The mean heat flow is determined as:
3. Logarithmic Mean Temperature Difference (LMTD)
LMTD is used to calculate the temperature driving force for heat exchange.
o For parallel flow:
o For counter flow:
6
4. Heat Transfer Coefficient Calculation
The overall heat transfer coefficient (
) is a measure of a heat exchanger's ability to
transfer heat. It is determined using:
5. Performance Comparison of Parallel and Counter flow.
Parallel Flow: Lower efficiency due to decreasing temperature difference between fluids.
Counter flow: Higher efficiency as the temperature difference remains larger throughout
the heat exchanger.
7
Figure 1: Shell and Tube Heat Exchanger
Figure 2: Counter Flow
Figure 3: Parallel Flow
8
MATERIALS AND APPARATUS
Materials:
 Hot and Cold Water – Used as the working fluids for heat exchange.
 WL 110 Heat Exchanger Unit – The main experimental setup for analyzing heat
transfer.
 WL 110.20 Refrigeration System – Provides controlled cold water supply.
 WL 110.01 Tubular Heat Exchanger – Used to study heat transfer in a single tube
configuration.
 WL 110.03 Shell-and-Tube Heat Exchanger – A multi-tube heat exchanger used for
more efficient heat transfer analysis
Apparatus:
The WL 110 unit consists of the following components:
•
Regulator for Cold Water: Controls the flow rate of cold water.
•
Regulator for Hot Water: Adjusts the flow rate of hot water.
•
Bolts and Couplings: Secure the connections within the heat exchanger system.
•
Control and Display Panel: Provides real-time temperature, flow rate, and heat
transfer data.
9
•
Left and Right Housing Sections: Encloses the heat exchanger components.
•
Tank Cover and Connecting Block: For maintaining the system's integrity.
•
Base Plate: Provides structural support.
The WL 110.20 unit includes:
•
Electronic Temperature Controller: Regulates cold water temperature.
•
Refrigeration System Switch: Controls the cooling mechanism.
•
Pump Switch: Manages cold water circulation.
•
Master Switch with Emergency Stop: Ensures safety during the experiment.
The WL 110.01 Tubular Heat Exchanger includes:
•
Cold Water Connections – Allows cold water to flow through the system.
•
Hot Water Connections – Enables hot water circulation.
•
Concentric Tubes – Facilitates heat exchange between the two fluids.
•
Temperature Sensors – Measure inlet and outlet temperatures.
The WL 110.03 Shell-and-Tube Heat Exchanger includes:
10
•
Tube Bundle Water Connection – Directs fluid into the tube section.
•
Shell Water Connection – Allows flow through the shell side.
•
Tube Bundle – Enhances the heat transfer area.
•
Transparent Shell – Provides visibility for monitoring fluid movement.
Figure 4: Experimental Setup of Shell and Tube Heat
11
METHODOLOGY
General and Operating Procedure
This experiment was conducted using the WL 110 heat exchanger apparatus and the WL 110.20 cold
water supply unit. The following detailed procedure was implemented to ensure consistent and
accurate data collection for both tubular and shell-and-tube heat exchangers, under both parallel and
counter flow configurations.
General Procedure:
1. Flow Direction and Software Initiation:
o
The desired flow direction (parallel or counter) was determined.
o
The appropriate software application for data acquisition was launched on the connected PC.
2. Equipment Activation:
o
The main power switches for both the WL 110 and WL 110.20 units were turned on.
3. Valve Opening:
o
The regulator valves for the cold water supply were opened first, followed by the valves for the hot
water supply.
4. Pump Activation:
o
The WL 110 pump was activated to circulate the hot water.
o
The WL 110.20 pump was activated to circulate the cold water.
12
Operating Procedure:
1. Cold Water Parameter Setting:
o
The cold water flow rate was set using the respective regulator valve.
o
The desired cold water temperature was set using the WL 110.20 controller. The cold water
temperature remained constant throughout the experiment.
2. Hot Water Parameter Setting:
o
The hot water flow rate was set using the respective regulator valve.
3. Heater Activation:
o
The refrigeration system's heater and switch were turned on.
4. Data Recording and Stabilization:
o
Data recording was initiated using the software program.
o
The system was allowed to reach a steady state, indicated by a constant hot water temperature and
similar heat flow rates for the hot and cold water streams.
o
Once a steady state was achieved, the measured values were recorded.
5. Parameter Variation:
o
Tubular Heat Exchanger: The hot water temperature was set to 35°C for the initial measurement
and subsequently increased to 45°C and 65°C for subsequent measurements, while the flowrate
remained constant.
o
Shell-and-Tube Heat Exchanger: The hot water temperature was maintained at a constant 65°C,
while the hot water flow rate was incrementally increased for each measurement.
6. Flow Direction Change and Repetition:
13
o
The flow direction was changed by adjusting the coupling connections.
o
The entire procedure (steps 5-8) was repeated with the same hot water temperature and flow rate
values for the new flow direction.
7. Equipment Shutdown:
o
Once all required data was recorded, the heater was turned off.
o
The pumps for both units were stopped.
o
The refrigeration system's switch was turned off.
o
All regulator valves were closed.
o
The main power switches for both units were turned off.
o
The devices were unplugged.
Safety Precautions
To ensure accurate results and maintain safety during the experiment, the following precautions
were taken:
Handling Glassware:
o Given the potential hazards associated with glass components, extreme care must be taken to prevent
breakage. Appropriate protective clothing, including safety glasses, should be worn at all times.
Water Leakage Prevention:
o As water is the primary fluid used in the experiment, the risk of leakage is significant. Regular checks
of all connections and seals are necessary to minimize this risk. Spills should be cleaned up
immediately to prevent slips or electrical hazards.
14
Electrical Safety:

The equipment operates on electrical power, necessitating careful handling of electrical connections.
Prior to plugging in any equipment, ensure that all plugs and sockets are completely dry. Moisture
can create a severe electrical shock hazard.
Wear Proper Protective Equipment (PPE)
o Always wear safety goggles, lab coats, and closed-toe shoes to protect against
accidental splashes.
o
If handling hot components, use heat-resistant gloves.
Follow Manufacturer Guidelines:
o Read and follow the WL 110 unit’s operating manual before starting.
o Do not exceed the recommended temperature or flow rate settings.
Emergency Preparedness:
o Know the location of the emergency shut-off switch, fire extinguisher, and first aid kit.
o In case of hot water leaks or electrical faults, turn off the system immediately and
inform the supervisor.
15
RESULT AND DISCUSSION OF THE RESULT
Result
For Tubular Heat Exchanger.
3 ρℎ = 1010
𝑘𝑔⁄
− 0.47
= 975.6
𝑚 ρ = 1010 − 0.47
Calculating the mass flow rates:
𝑚ℎ = 𝜌ℎ × 𝑉ℎ and 𝑚𝑐 = 𝜌𝑐 × 𝑉𝑐
Taking 𝑉ℎ = 2.16 and 𝑉𝑐 = 2.1
𝑘𝑔⁄
𝑚ℎ = 975.6
3 × 2.16 𝑚
= 2107.296 𝑘𝑔
3
= 2078.895 𝑘𝑔
𝑚
𝑘𝑔⁄
𝑚𝑐 = 989.95
3
3 × 2.1 𝑚
𝑚
The area values are also required:
𝐴ℎ = 1 × 3.14 × 10 𝑚𝑚 × 2 × 360 𝑚𝑚 = 0.022608 𝑚2
𝐴𝑐 = 1 × 3.14 × 12 𝑚𝑚 × 2 × 360 𝑚𝑚 = 0.0271296 𝑚2
16
Table 1: Tubular heat exchanger calculated parameters:
Flow
ΔT
ΔT
ΔT𝑳𝑴𝑻𝑫
Heat flow mean Heat transfer
Direction
maximum
minimum
(°C)
value,
coefficient’s
(°C)
(°C)
𝑸𝒎 (𝑘𝑊)
mean value, 𝑲𝒎
(𝑘𝑊⁄𝑚2𝐾)
Parallel
19.20
9.50
13.80
0.723
2.11
Parallel
32.60
16.80
23.83
1.169
1.97
Parallel
45.30
23.70
33.34
1.609
1.94
Counter
14.00
12.70
13.64
0.524
1.55
Counter
36.30
31.70
32.91
1.500
1.83
Counter
37.30
31.70
34.42
1.609
1.88
•
First data set (parallel flow)
∆𝑇𝑚𝑎𝑥 = 𝑇ℎ, − 𝑇𝑐,𝑖𝑛 = 38.1 − 18.9 = 19.2
∆𝑇𝑚𝑖𝑛 = 𝑇ℎ,𝑡 − 𝑇𝑐,𝑜𝑢𝑡 = 30.7 − 21.2 = 9.5
17
•
Second data set (parallel flow)
∆𝑇𝑚𝑎𝑥 = 𝑇ℎ, − 𝑇𝑐,𝑖𝑛 = 52 − 19.4 = 32.6
∆𝑇𝑚𝑖𝑛 = 𝑇ℎ,𝑡 − 𝑇𝑐,𝑜𝑢𝑡 = 41.4 − 24.6 = 16.8
•
Third data set (parallel flow)
∆𝑇𝑚𝑎𝑥 = 𝑇ℎ, − 𝑇𝑐,𝑖𝑛 = 65.2 − 19.9 = 45.3
∆𝑇𝑚𝑖𝑛 = 𝑇ℎ,𝑡 − 𝑇𝑐,𝑜𝑢𝑡 = 51.6 − 27.9 = 23.7
18
•
Fourth data set (counter flow)
∆𝑇𝑚𝑎𝑥 = 𝑇ℎ, − 𝑇𝑐,𝑜𝑢𝑡 = 36 − 22 = 14
∆𝑇𝑚𝑖𝑛 = 𝑇ℎ,𝑡 − 𝑇𝑐,𝑖𝑛 = 31.8 − 19.1 = 12.7
•
Fifth data set (counter flow)
∆𝑇𝑚𝑎𝑥 = 𝑇ℎ, − 𝑇𝑐,𝑜𝑢𝑡 = 63.2 − 26.9 = 36.3 ∆𝑇𝑚𝑖𝑛 = 𝑇ℎ,𝑜𝑢𝑡
− 𝑇𝑐,𝑖𝑛 = 50.7 − 19 = 31.7
•
Sixth data set (counter flow)
∆𝑇𝑚𝑎𝑥 = 𝑇ℎ, − 𝑇𝑐,𝑜𝑢𝑡 = 65.2 − 27.9 = 37.3
19
∆𝑇𝑚𝑖𝑛 = 𝑇ℎ,𝑡 − 𝑇𝑐,𝑖𝑛 = 51.6 − 19.9 = 31.7
For Shell and Tube Heat Exchanger.
ρℎ = 1010 − 0.47
ρ =
1010 − 0.47
Calculating the mass flow rates:
𝑚ℎ = 𝜌ℎ × 𝑉ℎ and 𝑚𝑐 = 𝜌𝑐 × 𝑉𝑐
Taking 𝑉ℎ = 0.72 and 𝑉𝑐 = 0.76
𝑘𝑔⁄
𝑚ℎ = 982.834
= 707.641 𝑘𝑔
3
= 758.599 𝑘𝑔
𝑚
𝑘𝑔⁄
𝑚𝑐 = 998.156
3
3 × 0.72 𝑚
3 × 0.76 𝑚
𝑚
The area values are also required:
𝐴ℎ = 7 × 3.14 × 4 𝑚𝑚 × 184 𝑚𝑚 = 0.01617728 𝑚2
20
Graph of Mean Heat against Logarithmic Mean
Temperature Difference
1.8
1.6
1.4
1.2
1
0.8
0.6
0.4
10
15
20
25
30
35
40
ΔT〗
_𝑳𝑴𝑻𝑫 (°C)
〖
Graph of Mean Coefficient of Heat Transfer against
Logarithmic Mean Temperature Difference.
2.2
2.1
2
1.9
1.8
1.7
1.6
1.5
1.4
10
15
20
25
ΔT〗
_𝑳𝑴𝑻𝑫 (°C)
〖
21
30
35
40
Table 2: Shell and Tube Heat Exchanger's calculated values:
Flow
ΔT
ΔT
Direction
maximum
(°C)
∆𝑇𝐿𝑀𝑇𝐷(°C)
Heat flow
Heat transfer
minimum
mean
coefficient’s
(°C)
value, 𝑸𝒎
mean
(𝑘𝑊)
𝒌𝒎
value,
(𝑘𝑊⁄𝑚2𝐾)
•
Parallel
38.10
19.10
27.52
0.477
0.86
Parallel
41.40
24.80
32.39
0.824
1.26
Parallel
41.90
26.40
33.36
1.140
1.69
Counter
38.60
26.60
32.23
0.737
1.13
Counter
39.30
31.10
35.04
1.128
1.59
Counter
40.60
33.20
36.78
1.571
2.11
First data set (parallel flow)
∆𝑇𝑚𝑎𝑥 = 𝑇ℎ, − 𝑇𝑐,𝑖𝑛 = 58.4 − 20.3 = 38.1
∆𝑇𝑚𝑖𝑛 = 𝑇ℎ,𝑡 − 𝑇𝑐,𝑜𝑢𝑡 = 49.1 − 30 = 19.1
22
•
Second data set (parallel flow)
∆𝑇𝑚𝑎𝑥 = 𝑇ℎ, − 𝑇𝑐,𝑖𝑛 = 61.7 − 20.3 = 41.4
∆𝑇𝑚𝑖𝑛 = 𝑇ℎ,𝑡 − 𝑇𝑐,𝑜𝑢𝑡 = 53.5 − 28.7 = 24.8
•
Third data set (parallel flow)
∆𝑇𝑚𝑎𝑥 = 𝑇ℎ, − 𝑇𝑐,𝑖𝑛 = 62.4 − 20.5 = 41.9
∆𝑇𝑚𝑖𝑛 = 𝑇ℎ,𝑡 − 𝑇𝑐,𝑜𝑢𝑡 = 54.8 − 28.4 = 26.4
•
Fourth data set (counter flow)
∆𝑇𝑚𝑎𝑥 = 𝑇ℎ, − 𝑇𝑐,𝑜𝑢𝑡 = 68.1 − 29.5 = 38.6
23
∆𝑇𝑚𝑖𝑛 = 𝑇ℎ,𝑡 − 𝑇𝑐,𝑖𝑛 = 47.5 − 20.9 = 26.6
•
Fifth data set (counter flow)
∆𝑇𝑚𝑎𝑥 = 𝑇ℎ, − 𝑇𝑐,𝑜𝑢𝑡 = 67 − 27.7 = 39.3
∆𝑇𝑚𝑖𝑛 = 𝑇ℎ,𝑡 − 𝑇𝑐,𝑖𝑛 = 51.6 − 20.5 = 31.1
•
Sixth data set (counter flow)
∆𝑇𝑚𝑎𝑥 = 𝑇ℎ, − 𝑇𝑐,𝑜𝑢𝑡 = 68 − 27.4 = 40.6
∆𝑇𝑚𝑖𝑛 = 𝑇ℎ,𝑡 − 𝑇𝑐,𝑖𝑛 = 53.6 − 20.4 = 33.2
24
Graph of the Mean Heat Flow and Logarithmic Mean
Temperature Difference
1.8
1.6
1.4
1.2
1
0.8
0.6
0.4
26
28
30
32
34
∆𝑇〗
_𝐿𝑀𝑇𝐷(°C)
〖
25
36
38
40
Graph of the Mean Coefficient and Logarithmic Mean
Temperature Difference
2.3
2.1
1.9
1.7
1.5
1.3
1.1
0.9
0.7
26
28
30
32
34
36
38
40
∆𝑇〗
_𝐿𝑀𝑇𝐷(°C)
〖
Discussion of Results
1. Mean Heat Flow (𝑸𝒎) vs. Logarithmic Mean Temperature Difference (∆𝑻𝑳𝑴𝑻𝑫)
Tubular Heat Exchanger:
The graph shows a positive linear relationship between 𝑸𝒎 and ∆𝑻𝑳𝑴𝑻𝑫, indicating that as
the temperature difference increases, the heat transfer rate also increases.
The trend is slightly nonlinear, suggesting that factors such as thermal resistance, flow
dynamics, and heat exchanger efficiency influence heat transfer performance.
Parallel flow configurations show higher
values at larger LMTD, but counter flow
configurations are generally more effective due to better temperature gradient utilization.
Shell and Tube Heat Exchanger:
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The heat flow also increases with LMTD, but at a slightly lower rate compared to the
tubular exchanger at lower LMTD values.
At higher ∆𝑻𝑳𝑴𝑻𝑫, the shell and tube heat exchanger surpasses the tubular exchanger in heat
transfer efficiency, showing its suitability for handling larger temperature differences.
Counter flow configurations again perform better than parallel flow, as expected.
2. Mean Heat Transfer Coefficient (𝑸𝒎) vs. Logarithmic Mean Temperature Difference
(∆𝑻𝑳𝑴𝑻𝑫).
•
Tubular Heat Exchanger:
The heat transfer coefficient slightly decreases as ∆𝑻𝑳𝑴𝑻𝑫 increases.
This could be due to reduced convective heat transfer efficiency or increased thermal
resistance as the temperature difference increases.
The slight decline in suggests that the heat exchanger might be less effective at higher
temperature differences due to limitations in heat transfer area or flow characteristics.
•
Shell and Tube Heat Exchanger:
Unlike the tubular heat exchanger, the heat transfer coefficient increases with LMTD.
This indicates that the shell and tube exchanger is more efficient at handling higher temperature
gradients, likely due to better turbulence and enhanced heat transfer mechanisms.
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At high LMTD values, the shell and tube heat exchanger outperforms the tubular exchanger,
showing its superiority for applications requiring high heat transfer rates.

Flow Configuration:
o
For both the tubular and shell-and-tube heat exchangers, the counter flow
configuration generally exhibited higher heat transfer rates (Qm) compared to the
parallel flow configuration. This is consistent with the theoretical understanding that
counter flow allows for a larger and more consistent temperature difference across the
heat exchanger, leading to improved heat transfer efficiency.
o
The LMTD values were also generally higher for counter flow, further supporting the
observation of enhanced heat transfer.

Temperature Difference:
o
In the tubular heat exchanger, as the temperature difference between the hot and cold
fluids increased (as seen in the parallel flow sets), there was a corresponding increase
in the heat flow rate (Qm). This demonstrates the direct relationship between
temperature difference and heat transfer.

Flow Rate:
o
In the shell-and-tube heat exchanger, where the flow rate was varied, an increase in
flow rate resulted in an increase in the heat transfer coefficient (Km). This indicates
that higher flow rates promote turbulence and improve the mixing of fluids, thereby
enhancing heat transfer.

Heat Transfer Coefficient (Km):
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o
The Km values varied significantly between the tubular and shell-and-tube heat
exchangers. The shell and tube exchanger showed lower values of Km. This is
expected, as the shell and tube design has a much larger surface area, and the heat
transfer coefficient is related to the surface area.
o
The values of Km varied throughout the experiments. This variation can be attributed
to multiple factors, including:

Experimental errors in temperature and flow rate measurements.

Heat losses to the surrounding environment.

Variations in fluid properties with temperature.

The stabilization of the system, that is, the system may not have fully reached
a steady state.

Mass flow rate
The mass flow rate calculations, using the density calculations, provided the required
information for the heat flow calculations. These values were as expected.
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CONCLUSION AND RECOMMENDATION
Conclusion
This experiment successfully investigated the heat transfer characteristics of tubular and shell-andtube heat exchangers using the WL 110 apparatus. The study effectively demonstrated the impact of
flow configuration, temperature difference, and flow rate on heat exchanger performance. The results
confirmed that the counter flow configuration consistently outperformed the parallel flow
configuration, achieving higher heat transfer rates and LMTD values in both types of heat exchangers.
This observation aligns with established heat transfer principles, highlighting the importance of flow
arrangement in optimizing heat exchanger efficiency.
Furthermore, the experiment revealed the direct influence of temperature difference and flow rate on
heat transfer performance. Increasing the temperature difference in the tubular heat exchanger resulted
in a proportional increase in heat flow, while increasing the flow rate in the shell-and-tube heat
exchanger led to a higher overall heat transfer coefficient. These findings underscore the importance
of operational parameters in achieving desired heat transfer outcomes.
The calculated values of key performance parameters, including mass flow rates, heat flow rates,
LMTD, and the overall heat transfer coefficient, provided valuable quantitative insights into the heat
exchanger's behavior. The experiment also provided practical experience in utilizing the WL 110
apparatus and its associated software for data acquisition and analysis.
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Recommendations:
Based on the findings of this experiment, the following recommendations are made to enhance future
studies and improve the practical application of heat exchangers:
1. Investigate the Effect of Fouling: Future experiments should consider the impact of fouling on heat
exchanger performance. Introducing controlled fouling conditions would provide valuable data on the
long-term efficiency and maintenance requirements of these systems.
2. Explore Different Working Fluids: This study used water as the working fluid. Future investigations
could explore the performance of heat exchangers with different fluids, such as oils or refrigerants, to
assess their suitability for various industrial applications.
3. Conduct Computational Fluid Dynamics (CFD) Simulations: CFD simulations can be used to
validate the experimental results and provide a deeper understanding of the flow and heat transfer
patterns within the heat exchangers. This would aid in optimizing the design and operation of these
devices.
4. Analyze Heat Losses: A more detailed analysis of heat losses to the environment should be
performed. Implementing insulation and conducting energy balance calculations would improve the
accuracy of the results.
5. Expand Range of Operating Conditions: Future experiments should expand the range of operating
conditions, including higher temperatures and flow rates, to explore the limitations and capabilities
of the heat exchangers.
6. Error Analysis: A thorough error analysis should be conducted to quantify the uncertainty associated
with the experimental measurements. This would enhance the reliability and validity of the results.
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7. Optimize Design Parameters: Further research should be conducted to optimize design parameters
such as tube diameter, length, and arrangement to maximize heat transfer efficiency for specific
applications.
8. Automated Data Acquisition: Utilizing more advanced data acquisition techniques, such as
automated data logging, would improve the accuracy and efficiency of future experiments.
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REFERENCES
Books
1. Incropera, F.P., & DeWitt, D.P. (2011). Fundamentals of Heat and Mass Transfer (7th ed.).
John Wiley & Sons.
2. ASHRAE. (2020). ASHRAE Handbook—HVAC Systems and Equipment. ASHRAE
3. Holman, J.P. (2010). Heat Transfer (10th ed.). McGraw-Hill.
4. Kakac, S., & Liu, H. (2002). Heat Exchangers: Selection, Rating, and Thermal Design (2nd
ed.). CRC Press.
5. WL 110 Heat Exchanger Unit Manual, GUNT Hamburg.
Websites
1. IRJET-V7I3697.pdf
2. https://www.appliancedesign.com/articles/93186-designing-for-efficient-heat-transfer
3. https://www.studocu.com/en-za/document/mangosuthu-university-oftechnology/chemical-engineering/heat-exchanger-pratical-report-for-chemicalengineering-students/25084868/
4. https://www.scribd.com/document/344602220/CPE533-Shell-and-Tube-HeatExchanger-Full-Lab-Report
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