We have created an apparatus to quantitatively measure two-dimensional heat flow in a metal plate using a grid of temperature sensors read by a microcontroller. Real-time temperature data are collected from the microcontroller by a computer for comparison with a computational model of the heat equation. The microcontroller-based sensor array allows previously unavailable levels of precision at very low cost, and the combination of measurement and modeling makes for an excellent apparatus for the advanced undergraduate laboratory course.

1.
There is no theoretical limit on the number of sensors that could be tied to the same bus. The available memory of the microcontroller and the cumulative current draw of all the sensors on the data line do provide a practical limit, however, and 100 sensors is approaching that limit.
2.
More information is available at <www.arduino.cc/>.
3.
Available at <www.sparkfun.com/>.
4.
Available at computer supply and repair stores.
5.
See supplementary material containing all programs used for the microcontroller and simulation can be found at http://dx.doi.org/10.1119/1.4867053.
6.
Y. A.
Cengel
and
A. J.
Ghajar
,
Heat and Mass Transfer: Fundamentals and Applications
, 4th ed. (
McGraw-Hill
,
New York
,
2011
).
7.
M.
DiStasio
and
W. C.
McHarris
, “
Electrostatic problems? relax!
,”
Am. J Phys.
47
(
5
),
440
444
(
1979
).

Supplementary Material

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