Students are always excited by doing real
engineering. Simulators that engineers use to design everything from
bridges to electrical circuits are a good way to capitalize on this
enthusiasm. They allow students to complete realistic designs in a reasonable
amount of time, and there are versions for all engineering disciplines.
There are some disadvantages to simulators. They can be
relatively expensive. They require a high-end PC or workstation, coding
for unusual problems, or inputting of physical property data, which
makes them less user-friendly than generic programs. Not only that,
simulators generally have overly detailed manuals and offer only rudimentary
help. They also assume users know what they are doing, so there are
no checks on carelessness.
Unless students have learned how to use the simulator
in a prerequisite course, practice sessions in a computer laboratory
will probably be necessary. We use sections of 20 students scheduled
for two hours per week, although they typically meet only six or so
times a semester. One of the lectures is replaced with an optional help
session during the week of the computer laboratory.
Some lecturing on simulator use is helpful, but too much
can make students' eyes glaze over. The start of most simulatorslogging
on, picking units, choosing interconnections, selecting a file nameconsists
of a series of arbitrary steps. Because these steps are arbitrary, logic
or engineering knowledge won't help the new user get through them. Manuals,
in covering all possible options, sometimes devote up to 50 pages just
to explain the basics. If available, use a simplified starting manual.
Otherwise, write your own, outlining the starting procedure sans the
bells and whistles. When the start-up instructions have been completed,
have your teaching assistant do a beta test of the procedures. Such
testing should be done yearly because of changes in both the simulator
and the university operating systems.
Once students graduate and confront new simulation systems
on the job, they may not have the luxury of formal training. Thus, in
the engineering part of the simulator, give them just enough instruction
to make simple things work and encourage them to explore the simulator
on their own. This explore-on-your-own procedure works best if someone
knowledgeable is available to answer questions and help troubleshoot.
Otherwise, relatively small computer problems can generate immense frustration.
Simulators should not be black boxesthe students
need to know the theories being used. Have students check a few simple
problems with a calculator and thoroughly discuss the assumptions inherent
in the model. If the simulator allows a choice of models (e.g. vapor-liquid
equilibrium correlations), have the students compare results with different
choices, including one that is clearly inappropriate.
As in all curricular matters, some repetition reinforces
learning, so pick simulators that will be useful in several courses.
You will know students are learning when they voluntarily use the simulator
in one of your later courses.
Phillip Wankat is head of interdisciplinary engineering
and the Clifton L. Lovell Distinguished Professor of chemical engineering
at Purdue University. Frank Oreovicz is an education communications
specialist at Purdue's chemical engineering school. They can be reached
by e-mail at firstname.lastname@example.org