# Thermal Technology

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```							Thermal Technology
1.   Use computers and calculators to access, retrieve, organize, process,
maintain, interpret, and evaluate data and information in order to
communicate. (ITEA, STL 12-P).
2.   Document processes and procedures and communicate them to different
audiences using appropriate oral and written techniques. (ITEA, STL 12-L)
3.   Identify and describe applications of thermal technology in the designed
world such as thermometer, refrigerator, furnace, air conditioner, and heat
engines.
4.   Explain science concepts and mathematical concepts applied in thermal
technology such as convection, conduction, radiation, insulation, and
efficiency.
Engineering, the systematic application of

mathematical, scientific, and technical principles,

produces tangible end products that meet our

needs and desires.
• To familiarize students with the functioning and
applications of thermal technology systems by
having them analyze the functioning of thermal
systems in terms of their common components,
basic system design, safety considerations, and
simple controls.
• Student groups will investigate one of the properties of heat energy
using the following apparatus:
– cup painted white, cup painted black, graduated cylinder, water, two
thermometers, incandescent light (100W lamp), measuring tape or ruler,
clock.

• Students will use the graduated cylinder to measure an equal
amount of water into both containers so that they are about half
full.
• Students will measure the temperature of the water in each
container and record these temperatures as the temperatures at
time zero minutes.
• Students will set the light so that it is the same distance from each
container. Turn the lamp on and start the timer. After one minute,
measure and record the temperature in each container.

• Continue to measure and record the temperature of each container
every minute for ten minutes.

• Students will use a spreadsheet program to organize their data

• Students will construct a graph of time vs. temperature for their
investigation. Plot the data from each container on the same graph
using a different color for each container.
Time   Temp (white cup)   Temp (black cup)
0
1
2
3
4
5
6
7
8
9
10
Make a graph using Microsoft Excel
1. Which container showed the greater increase in temperature?
2. Which container absorbed more energy and how do you know this?
3. What was the source of heat in this experiment?
4. What were the controlled factors in this experiment?
5. Why was it important to keep these factors the same for both containers?
6. If you were going to use radiant energy from the sun to heat your home, what colors
7. If the containers used in this experiment were filled with hot
water, which one do you think would cool off more slowly?
8. Describe an experiment that you could do to test your

hypothesis.
HOMEWORK

• Bring in a recycled 3 panel display board from
your Science Fair project, or a large flat sheet of
cardboard at least 3’ x 4’.

• You can check with your science teacher to see if
they have some left from the science fair.
Thermal Technology –
• The technology of producing,
storing, controlling, transmitting and
getting work from heat energy.

•Example applications: furnace, hot water
heater, toaster, insulation, heat exchanger,
refrigerator, jet engine, hot air balloon.
A. The universe is made up of matter and
energy.
B. Matter is made up of atoms and molecules
(groupings of atoms)
- energy causes the atoms and molecules to always be in
motion—either bumping into each other or vibrating back
and forth.

C. The motion of atoms and molecules creates
a form of energy called heat (or thermal
energy) that is present in all matter.
D. Thermodynamics is the science
dealing with internal energy, heat,
and work.

E. Even in the coldest voids of
space, matter has a very small
but still measurable amount of
heat energy.

F. Energy can take on many forms
and can change from one form to
another.
G. Many different types of energy can be converted into
heat energy:
-Light, electrical, mechanical, chemical, nuclear, sound,
and thermal energy can each cause a substance to heat
up by increasing the speed of its molecules.

H. Put energy into a system and it heats up; take energy
away and it cools.
-(For example, when we are cold, we can jump up and down to get warmer.)
A few examples of various types of energy being converted into
thermal energy (heat) including:
1. Mechanical energy is converted into thermal energy whenever
you bounce a ball.
2. Electrical energy is converted into thermal energy
- electrical stove elements, toasters, hair dryers, or light bulbs.
3. Chemical energy from the foods we eat is converted into
heating our bodies.
4. Light from the sun is converted to heat as the sun’s rays warm
the earth’s surface.
Heat can be transferred from
one place to another by three
methods:

1. conduction in solids
2. convection of fluids (liquids or gases)
3. radiation through anything that will allow
1. Thermal resistance is a measure of an object’s ability to oppose
heat transfer.
2. Materials with high thermal resistance are used to insulate an
object or a region of space.

Walls are often constructed of layers of
materials of varying thermal conductivity.
(A house wall may consist of a layer of half-inch
sheetrock, a layer of three inch thick insulation,
and an outer layer of brick four inches thick.)
Calculate the thermal resistance
1/2” - Sheetrock   3” - Insulations   4” - Brick

Material             Thermal
Conductivity
Btu • ft2• °F
Sheetrock                     5.2
Insulation                   0.32
Brick                         408
The area of the wall is equal to 300 sq ft.

Calculate the thermal resistance (R) of each layer, where:

thickness of material (in)
R=       thermal conductivity x area of wall

Rtotal= R1 + R2 + R3
thickness of material (in)
R=      thermal conductivity x area of wall

0.5 in                                 h · °F
R1=                                   =    0.00032
5.2 x 300 ft2                             BTU

R2=             3 in              =       0.031    h · °F
.32 x 300 ft2                          BTU

4 in                 =    0.0028     h · °F
R3=        4.8 x 300 ft2                            BTU

0.034    h · °F
Rtotal= R1 + R2 + R3        =                 BTU
Construct a Solar Collecting House

1. Determine which insulating material holds
heat the best.
a) All material must be 1/2 inch thick.
b) Must cover all walls and floor.
c) A closed 7 ½”” x 10 1/2” window will
be used to allow light to heat the
interior for 10 minutes.
d) You choose your own colors.
2. Record data and represent it in graph form.
14 inches

Window opening will be 7                   12 inch equal
1/2” x 10 1/2” centered               lateral triangle sides
Something to Consider….
Conducting the experiment:
1. Record the starting temperature of the Solar House.
2. Heat the Solar House for 10 minutes.
3. Record the temperature drop without any lining materials. (this
provides a set of data to compare your linings to)
4. Line the Solar House with the material selected and measure the
temperature every 30 seconds during the heating and cooling
stages. Repeat this process twice and average the results.
5. After the data has been collected, recorded the results on a chart
and displayed in a graph.

```
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