SUNY Maritime College Transport Processes Laboratory Dr. Peter K. Domalavage Heat Conduction Laboratory Spring 2014 Group C3 05/01/2014 Hail Munassar- Leader Andrew Butler- Analyst Matt Thomas - Pictures Josh Smith – Data Collector Christopher Morsch – Called out Data
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SUNY Maritime College Transport Processes Laboratory
Dr. Peter K. Domalavage
Heat Conduction Laboratory
Spring 2014
Group C3
05/01/2014
Hail Munassar- Leader
Andrew Butler- Analyst
Matt Thomas - Pictures
Josh Smith – Data Collector
Christopher Morsch – Called out Data
Abstract
The following report contains data, and analysis of said data, showing the results of heat
transfer through different materials and different shapes. The first data set that was collected was
for a rod made of carbon steel and copper with a single steady cross sectional area; this means
the diameter of the rod stayed consistent through its entire length. When we arrived the furnace
was already in a steady state condition, so we just turned the dial to the numbers that
corresponded to the thermocouples, the temperature for each thermocouple was recorded. This
was repeated for the next three materials; number two was a rod with a single, steady cross
sectional area and was made of aluminum and magnesium. The third set of data was different
from the first two because it was collected from a rod with a cross sectional area that got
gradually larger from a 1”diameter at the base to a 2”diameter at the top. The fourth and final set
of data was more similar to the first two in that it was a consistent cross sectional area, but it was
different because it was only one metal instead of two. Once all data was collected it was used to
graph and analyze temperature with respect to distance across all four materials.
Table of Contents
Nomenclature ……………...…………………………………………… 1
Description of heat conduction ……………………………………… 1
Introduction ……...…………………………………………………… 2
Procedures ………………………………...………………………… 3
System Schematic …………………………………………………… 4
Data ………………….……………………………………………… 5
Raw of Data …………………………………………………… 5
Configuration 1 …………………………………………………… 6
Basic Diagram …………………………………………………… 6
Analysis …………………………………………………… 6
Results …………………………………………………… 7
Configuration 2 …………………………………………………… 7
Basic Diagram …………………………………………………… 7
Analysis …………………………………………………… 8
Results …………………………………………………… 8
Configuration 3 …………………………………………………… 9
Basic Diagram …………………………………………………… 9
Analysis …………………………………………………… 9
Results …………………………………………………… 9
Configuration 2 …………………………………………………… 10
Basic Diagram …………………………………………………… 10
Analysis …………………………………………………… 10
Results …………………………………………………… 10
Materials Tested .…………………..……………………………………… 11
Conversions …………………………………………………… 12
Material Data …………………………………………………… 12
Carbon Steel …………………………………………………… 12
Copper …………………………………………………… 12
Aluminum …………………………………………………… 13
Magnesium …………………………………………………… 13
Discussion ……...…………………..……………………………………… 13
Description of Curves ………………………...…………………. 13
Differences in Curves and Purpose …………...…………………. 14
Question 1 ……….………………………...…………………. 15
Question 2 ……….………………………...…………………. 16
Question 3 ……….………………………...…………………. 16
Outcome ……...…………………..……………………………………… 18
Conclusion ……...…………………..……………………………………… 18
References ……...…………………..……………………………………… 19
Appendix ……...…………………..……………………………………… 20
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Nomenclature
symbol definition units
Q rate of heat flow; qk, rate of heat flow by
conduction
S.I. - W
US - Btu/h
K thermal conductance; Kk, thermal
conductance for conduction heat
transfer
S.I. - W/K
US - Btu/h °F
A area; Ac cross-sectional area
S.I. – M2
US – FT2
dT/dx Rate of temperature change; Temperature change over
distance S.I. – ⁰C/cm
UM – ⁰F/in
Description of heat conduction
There are three modes of heat transfer: conduction, convection, and radiation. Heat that is
conducted through a material is heat that is transferred internally, through the vibrations of atoms
and molecules.1 It occurs in both solids and fluids. Conduction heat transfer is driven by
temperature differentials. For example, if one end of a metal rod is at a higher temperature,
energy will shift towards the colder end. The internal energy shift consists of disorganized
kinetic and potential energy. “For most engineering problems, it is impractical and unnecessary
to track the motion of individual molecules and electrons, which may instead be described using
the macroscopic averaged temperature.”2
1 N.d. TS 12-6-99. Boston University. Physics. Web. 1 May 2014.
2 "Heat Conduction." Thermal-Fluids Central. N.p., 5 Aug. 2010. Web. 1 May 2014.
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The heat conduction process is modeled by Fourier’s law and thermodynamics of energy
conservation. 3 The resulting mathematical descriptions can be written as ordinary of partial
differential equations. Conduction heat transfer is the simplest of the three modes to solve
mathematically, and has been studied the longest. “Famous math mathematicians, including
Laplace and Fourier, spent part of their lives seeking and tabulating useful solutions to heat
conduction problems.” 4 Different engineering applications can be represented by one of two
situations; time dependent of not time dependent. A time dependent situation is referred to as
transient conduction. Situations that do not depend on time are referred to as steady state
conduction. All of our experiments are at a steady heat flow rate.
Fourier’s heat equation is Q=KA dT/dx. Q is the rate of heat flow (cal/s), K is the thermal
conductivity of the material (cal/sec-cm °C ), A is area (cm2), and dT/dx is the rate of change of
temperature per unit length (°C/cm).
Introduction
This Labs purpose is to show a Maritime College Engineer the effects material and cross
sectional area have on heat transfer through conduction. By observing the system characteristics
students can see the change in temperature across the heat exchanger and compare how cross
sectional area and material type affects them. They can then relate this to the data they collect
and use it to get a better understanding on the reason for using different materials and sizes for
heat transfer in real world applications. It also helps the students to understand the best
applications for different materials and size configurations. By combining this usage of an actual
heat exchanger and relating it to real data gathered on it, a better understanding of heat transfer
can be gained.
3 Kreith, Frank, and Mark Bohn. "Heat Conduction." Principles of Heat Transfer. 7th ed.
4 Kreith, Frank, and Mark Bohn. "Heat Conduction." Principles of Heat Transfer. 7th ed.
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Procedures
1. Set up heat exchangers and administer heat source.
2. Admit cooling water hose and adjust valve to maintain steady cooling water flow.
Note: Avoid unintentional valve adjustments. This will change the rate of cooling water flow
and skew data***
3. Allow for temperatures to stabilize.
4. Set digital meter to display readings from Material #1.
5. Cycle through thermocouples 1-10 while recording each temperature.
6. Set digital meter to display readings from Material #2.
7. Cycle through thermocouples 1-10 while recording each temperature.
8. Set digital meter to display readings from Material #3.
9. Cycle through thermocouples 1-10 while recording each temperature.
10. Set digital meter to display readings from Material #4.
11. Cycle through thermocouples 1-10 while recording each temperature.
12. Once you have recorded all data, repeat steps 4 – 11 and compare results.
Note: This will ensure that both experiments were completed under the same conditions
without any fluctuations.
13. Turn off heating supply.
14. Shut off cooling water and disconnect.
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System Schematic
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Data
Raw Data
Temperature for Each Thermocouple for Each Configuration
Conductivity (K) Values
1 2 3 4
1 239 243 260 296
2 165 166 252 292
3 115 104 245 288
4 110 96 240 284
5 107 88 235 281
6 104 80 231 277
7 91 66 227 274
8 76 58 224 271
9 62 50 222 268
10 49 41 220 265
Ther
mo
cou
ple
#
Configuration # (Temps in ̊C)
0.3
0.13
MaterialCopper
Aluminum
Magnisum
Carbon Steel
K (Cal/(cm-s ̊C)0.9
0.5
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Configuration 1
Steady State Heat Flow for Different Materials
Basic Diagram
Analysis
Temperature Change with Distance
Material Thermo # Distance (cm) Temp( ̊C)
Steel 1 0 239
2 0 165Steel
Copper
3 2.54 115
4 6.98 110
5 11.42 107
6 15.86 104Coppe
r
Carbon
Ste
el
7 23.48 91
8 27.92 76
9 32.36 62
10 36.8 49Carbon
Ste
el
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Results
Configuration 2
Steady State Heat Flow for Different Materials
Basic Diagram
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Analysis
Temperature Change with Distance
Results
Material Thermo # Distance(cm)Temp ( ̊C)
Steel 1 0 243
2 0 166Steel
Alumin
um
3 2.54 104
4 6.98 96
5 11.42 88
6 15.86 80Alum
inum
Mag
nesiu
m
7 23.48 66
8 27.92 58
9 32.36 50
10 36.8 41
Mag
nesiu
m
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Configuration 3
Steady-state heat flow for a variable cross-section
Basic Diagram
Analysis
Temperature Change with Distance
Results
Thermo # Distance Temp
1 4.92125 260
2 7.381875 252
3 9.8425 245
4 12.30313 240
5 14.76375 235
6 17.22438 231
7 19.685 227
8 22.14563 224
9 24.60625 222
10 27.06688 220
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Configuration 4
Steady-state heat flow for constant cross section
Basic Diagram
Analysis
Results
Thermo # Distance Temp
1 4.92125 296
2 7.381875 292
3 9.8425 288
4 12.30313 284
5 14.76375 281
6 17.22438 277
7 19.685 274
8 22.14563 271
9 24.60625 268
10 27.06688 265
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Materials Tested
For this experiment we are looking at thermal properties of various materials. Thermal
conductivity is a coefficient that represents the rate at which heat moves through a specific
material. Some materials allow heat to move quickly through them, some materials allow heat to
move very slowly through them.5 The higher the coefficient of thermal conductivity (K), the
faster the rate of heat transfer through that material. Copper has a thermal conductivity of 401
W/m°K while air as a coefficient of .026 W/m°K.
Specific heat tells us how much will the temperature of an object increase of decrease by
the gain or loss of energy.6 It is important to note that the specific heat is per unit mass therefore
the specific heat of a gallon of water is equivalent to the specific heat of a liter of water. For
example, the specific heat of copper is .385 J/g°C. This tells you that it takes .385 joules of heat
to raise 1 gram of copper 1 °C.7 Thermal diffusivity represents the ability of a material to conduct
thermal energy relative to its ability to store energy. The thermal coefficient of diffusivity is
calculated by thermal conductivity/ (coefficient of specific heat*density) at a constant pressure.
The thermal expansion coefficient is a standard measure of a substances expansion to
changes in temperature. It quantifies the magnitude of a material’s reaction to temperature
fluctuations. This is extremely important to structural engineers.
5 http://phun.physics.virginia.edu/topics/thermal.html, 1, May 2014 6 http://engineershandbook.com/Materials/thermal.htm, 1, May 2014 7 http://www.engineeringtoolbox.com/specific-heat-metals-d_152.html, 1, May 2014