To: Professor LaFleur
From: Paul Lakatos, Mike Hayes, Shane Young
Re: ME401, Heated Bar Memo
Section: 21
Certification: ______________________________________
Revision Date:_____________________________________
Summary:
The purpose of this experiment was to analyze the heat transfer properties of a copper
bar. There are eight RTD’s attached to the bar to measure temperature along the length of the
bar. These act as eight nodes, with seven elements, along which properties such as the
convection coefficient can be measured. There is a heater attached to one end of the bar and
cooling fins attached to the other. The heater brought the bar from room temperature to almost
100 degrees C and temperature data was recorded at each point.
Task 1:
For task one we were asked to take the heated bar data we recorded and section it into
three sections. The first section shown by figure (1) is the transient heat up of the bar from room
temperature approaching steady state. Figure (2) shows the bar at its closest point to reaching
steady state. We turned off our apparatus before fully achieving a steady state. And lastly figure
(3) shows the transient cool down of our bar from the steady state back to room temperature. It
can be seen that the lower two lines representing the last RTD sensors begin to cross. This makes
no logical sense since its saying that the end of the bar is hotter that the point before it.
Figure (1): Transient Heat Up
4.8 4.81 4.82 4.83 4.84 4.85 4.86 4.87 4.88 4.89 4.9
x 10
4
20
30
40
50
60
70
80
time [s]
Temperature [C]
Transient Heat up Temp vs. Time
5.05 5.06 5.07 5.08 5.09 5.1 5.11 5.12
x 104
40
50
60
70
80
90
100
time [s]
Temperature [C]
0.008
0.009
0.01
0.011
0.012
0.013
0.014
0.015
Biot Number