Heat Transfer Lab
Lab Report #1
Group Number:8
Name Registration no:
Qazi Nasrullah 220101071
Jawad Hassan 220101097
Ali Haider 220101087
AERO 21-A
Submitted to: Sir Amber
Safety rules:
➢ Make sure to read all fire alarm and safety signs and follow the instructions in the event
of an accident or emergency
➢ Be aware of the facility's/building's evacuation procedures
➢ Make sure to know where the lab's safety equipment including first aid kit and fire
extinguisher are located and how to properly use them
➢ Know emergency phone numbers for help in case of an emergency
➢ Do not touch electrical equipment during operation with wet hands
➢ Do not touch high temperature equipment during operation as it may cause serious bums
➢ Do not chew gum, drink, or eat while working in the lab
➢ Never use lab equipment that you are not approved or trained by your supervisor to
operate
➢ Do not wear loose clothing
➢ If an instrument or piece of equipment fails during use, or isn't operating properly, report
the issue to a lab engineer/technician right away. Never try to repair an equipment
problem on your own
➢ Report all injuries, accidents, and broken equipment or glass right away, even if the
incident seems small or unimportant
➢ In case of an injury, yell out immediately to get quick help does not leave the experiments
unattended while in progress
➢ Do not crowd around the equipment's & run inside the laboratory
Conduction:
Conduction is the transfer of energy from the more energetic particles of a
substance to the adjacent less energetic ones because of interactions between the particles.
Conduction can take place in solids, liquids, or gases. In gases and liquids, conduction is due to
the collisions and diffusion of the molecules during their random motion. In solids, it is due to
the combination of vibrations of the molecules in a lattice and the energy transport by free
electrons. For example, a cold canned drink in a warm room eventually warms up to the room
temperature because of heat transfer from the room to the drink through the aluminum can by
conduction.
Convection:
Convection is the mode of energy transfer between a solid surface and the
adjacent liquid or gas that is in motion, and it involves the combined effects of conduction and
fluid motion. The faster the fluid motion, the greater the convection heat transfer. In the absence
of any bulk fluid motion, heat transfer between a solid surface and the adjacent fluid is by pure
conduction.
Convection is called forced convection if the fluid is forced to flow over the surface by
external means such as a fan, pump, or the wind. In contrast, convection is called natural (or
free) convection if the fluid motion is caused by buoyancy forces that are induced by density
differences due to the variation of temperature in the fluid.
Radiation:
Radiation is the energy emitted by matter in the form of electromagnetic waves (or
photons) because of the changes in the electronic configurations of the atoms or molecules.
Unlike conduction and convection, the transfer of energy by radiation does not require the
presence of an intervening medium. In fact, energy transfer by radiation is fastest (at the speed of
light) and it suffers no attenuation in a vacuum.
Black body radiation:
The idealized surface that emits radiation at maximum rate is called a
blackbody, and the radiation emitted by a black body is called blackbody radiation. The
radiation emitted by all real surfaces is less than the radiation emitted by a blackbody at the same
temperature.
1) Shell and Tube Heat Exchanger
A shell and tube heat exchanger are a type of heat exchanger used to transfer heat between two fluids. It
consists of a cylindrical shell containing a bundle of tubes. The tubes run through the shell, and the two
fluids flow through the tubes and the shell, respectively. Baffles are inserted into the shell to create
turbulence and improve heat transfer.
How It Works
In a shell and tube heat exchanger, one fluid flows through the tubes, while the other fluid flows through
the shell. The two fluids are separated by the tube walls. Heat is transferred between the two fluids
through the tube walls, either by conduction or convection. The specific design of the heat exchanger,
including the tube arrangement, baffle spacing, and flow rates, determines the efficiency of heat transfer.
Common Applications
Shell and tube heat exchangers are used in a wide range of industrial processes, including:
• Power plants: To heat or cool water, steam, or other working fluids.
• Oil and gas: To heat or cool crude oil, natural gas, or refinery products.
• Chemical processing: To heat or cool reactants or products in chemical reactions.
• Food and beverage processing: To pasteurize or sterilize food and beverages.
• Refrigeration: To cool or condense refrigerants.
Example Experiment
An experiment to evaluate the performance of a shell and tube heat exchanger could involve the following
steps:
1. Select two fluids with known properties: The fluids should have different temperatures and
specific heat capacities.
2. Measure the flow rates of the two fluids: The flow rates should be controlled and measured
accurately.
3. Measure the inlet and outlet temperatures of both fluids: This will allow for the calculation of
the heat transfer rate.
4. Vary the operating conditions: The experiment can be repeated with different flow rates, inlet
temperatures, or baffle configurations to assess their impact on heat transfer performance.
5. Analyze the data: The collected data can be used to calculate the overall heat transfer coefficient
(U) and compare it to the theoretical value.
2) Linear/Radial Heat Conduction Apparatus:
Linear/radial heat conduction apparatuses are laboratory equipment designed to study and measure the
rate of heat transfer through different materials under specific conditions. These devices are essential for
understanding thermal conductivity, a fundamental property of materials that determines how efficiently
they conduct heat.
Types of Heat Conduction
• Linear Heat Conduction: In this type, heat flows in a straight line, typically between two
parallel surfaces.
• Radial Heat Conduction: Here, heat flows radially outward or inward, often from a central
source or sink.
Components of a Typical Apparatus
1. Heat Source: This can be a heating element, hot water bath, or other means to provide a constant
heat flux.
2. Test Specimen: The material whose thermal conductivity is to be measured. It is usually shaped
as a rod or cylinder for linear or radial conduction, respectively.
3. Temperature Sensors: These are placed at various points along the test specimen to measure
temperature gradients.
4. Insulation: To minimize heat losses to the surroundings and ensure that heat flows primarily
through the test specimen.
5. Data Acquisition System: To record and analyze temperature data.
Applications of Linear/Radial Heat Conduction Apparatus
• Material Research: Determining thermal conductivity of various materials, including metals,
alloys, ceramics, and polymers.
• Thermal Engineering: Designing heat exchangers, insulation systems, and other thermal
components.
• Process Control: Monitoring and controlling heat transfer in industrial processes.
• Education: Demonstrating heat conduction principles in physics and engineering laboratories.
Experimental Procedures
1. Preparation: Mount the test specimen between the heat source and the heat sink. Ensure good
thermal contact.
2. Temperature Measurement: Record the temperatures at different points along the specimen.
3. Data Analysis: Use Fourier's law of heat conduction to calculate the thermal conductivity from
the temperature gradient and heat flux.
4. Repeat: Conduct multiple experiments under varying conditions (temperature, specimen length,
etc.) to obtain reliable results.
3) Thermal Conductivity Apparatus for Liquids and Gases
How It Works
A thermal conductivity apparatus designed for liquids and gases typically uses a heated wire or plate as a
heat source. The sample fluid is placed around the heat source, and the temperature difference between
the heat source and the surrounding fluid is measured.
The thermal conductivity of the fluid can be calculated using the following equation:
k = Q / (A * d * dT/dx)
where:
• k is the thermal conductivity of the fluid
• Q is the rate of heat transfer
• A is the surface area of the heat source
• d is the distance between the heat source and the temperature sensor
• dT/dx is the temperature gradient
Common Applications
Thermal conductivity apparatus for liquids and gases are used in a variety of applications, including:
• Chemical engineering: To study the properties of different fluids
• Materials science: To characterize new materials
• Environmental science: To measure the thermal conductivity of natural waters and gases
• Food science: To evaluate the thermal properties of food products
Example Experiment
Objective: To determine the thermal conductivity of a liquid.
Materials:
• Thermal conductivity apparatus for liquids
• Liquid sample
• Heating element
• Temperature sensors
• Data logger
Procedure:
1. Fill the apparatus with the liquid sample.
2. Apply a constant heat flux to the heating element.
3. Measure the temperature difference between the heating element and the surrounding liquid.
4. Calculate the thermal conductivity of the liquid using the equation above.
4) Hydraulic Bench
How It Works
A hydraulic bench is a laboratory equipment used to demonstrate the principles of hydraulics and fluid
mechanics. It typically consists of a reservoir, pumps, valves, pipes, and various components that allow
for the control and measurement of fluid flow and pressure.
The reservoir stores the fluid, which is then pumped through the system. Valves are used to control the
flow direction and rate, while pipes and fittings connect the components. Different components, such as
orifices, nozzles, and venturis, can be added to the system to study specific hydraulic phenomena.
Common Applications
Hydraulic benches are used in a variety of educational and research settings, including:
• Engineering schools: To teach students about hydraulic principles and applications
• Research laboratories: To conduct experiments on fluid flow and hydraulic systems
• Industrial settings: To test and calibrate hydraulic components and systems
Example Experiment
Objective: To determine the relationship between flow rate and pressure drop in a pipe.
Materials:
• Hydraulic bench
• Pipe
• Flow meter
• Pressure gauges
• Data logger
Procedure:
1. Connect the pipe to the hydraulic bench.
2. Set the pump to a desired flow rate.
3. Measure the pressure drop across the pipe.
4. Repeat steps 2 and 3 for several different flow rates.
5. Plot the pressure drop against the flow rate.
5) Unsteady State Heat Transfer Apparatus
How It Works
An unsteady state heat transfer apparatus is a laboratory equipment used to study the transient behavior of
heat transfer in a material. It typically consists of a heating element, a sample holder, and temperature
sensors.
The heating element is used to apply a heat flux to the sample, while the temperature sensors measure the
temperature at different points within the sample over time. The temperature distribution in the sample
will change as heat is transferred through the material.
Common Applications
Unsteady state heat transfer apparatus are used in a variety of educational and research settings, including:
• Engineering schools: To teach students about heat transfer principles and applications
• Research laboratories: To study the thermal properties of materials
• Industrial settings: To test and optimize thermal processes
Example Experiment
Objective: To determine the thermal diffusivity of a material.
Materials:
• Unsteady state heat transfer apparatus
• Sample material
• Heating element
• Temperature sensors
• Data logger
Procedure:
1. Place the sample material in the sample holder.
2. Apply a constant heat flux to the sample using the heating element.
3. Measure the temperature at different points within the sample over time.
4. Analyze the temperature data to determine the thermal diffusivity of the material.
6) Heat Transfer Control Panel
Description: This is a control panel used in heat transfer experiments. It has digital displays that
show temperatures and a flow rate, along with switches to control heaters and pumps. It helps
control and measure temperature changes in heat-related experiments.
Experiment:
• Thermal Conductivity of a Solid (Conduction)
• Linear Heat Conduction Through a Composite Wall
• Forced Convection in a Duct
Example: You can test the thermal conductivity of a metal rod by heating one end and
measuring the temperature at different points along the rod.
7) Linear Motion Material Testing Setup
Description: This setup is used to test how materials react to forces along a straight line. It has a
track where materials are placed and a device to measure how much they stretch or move.
Experiment:
• Tensile Test
• Compression Test
• Bending or Flexural Test
• Hardness Test
Example: You can measure how much a metal stretches before breaking by applying force and
recording the length change.
8) Free and Forced Convection Apparatus
Description: This machine is used to study how heat moves in fluids (like air) through free or
forced convection. It has displays to monitor temperature and switches to control fans and
heaters.
Experiment:
• Free (Natural) Convection Experiment
• Forced Convection Experiment
• Comparison of Free and Forced Convection
• Effect of Surface Orientation on Natural Convection
• Effect of Flow Velocity on Forced Convection
Example: You can measure how quickly air takes heat away from a hot surface by changing the
air speed and recording the temperature changes.
9) Cross Flow Heat Exchanger
Description:
This setup has a control panel with switches and meters that show temperature readings. There
are controls for adjusting the flow rates and power settings. The wires connected to it are likely
for temperature sensors or controlling fans and pumps. It’s mounted on a frame, making it
suitable for lab experiments where you can measure heat transfer under controlled conditions.
Experiments:
• Heat Transfer in a Cross Flow Heat Exchanger
• Effectiveness of the Cross Flow Heat Exchanger
• Log Mean Temperature Difference (LMTD) Method
• Effect of Flow Rate on Heat Transfer Coefficient
• Parallel Flow vs. Counter Flow Comparison
Example Experiment: Measure the heat transfer rate and compare it with theory.
