How To Rescue A Poorly Operating Experiment In An Engineering Technology Lab And Turn It Into A "Real World" Learning Lesson

A planned experiment that goes awry can never be completely avoided. Even the best planned lab experiment in an engineering technology course will suffer a somewhat embarrassing failure in the middle of the experiment, with a lab team of engineering technology students looking on, dispirited and possibly embarrassed for the seemingly helpless instructor. But this is the precise moment and opportunity when the engineering technology lesson can be enlivened and saved from failure and when the instructor can provide the greater lesson to the student which, in the words of the non-engineer Winston Churchill is: never give up, never give up, never give up! This paper explores the strategy of turning a lab experiment failure into an engineering technology learning lesson that will not soon be forgotten by the engineering technology student. Background and Introduction Any Instructor or Teaching Assistant has likely had the experience of starting an engineering laboratory experiment only to find that the experiment does not work completely. This can be true even when the experiment “...worked a minute ago” during the trial test; before the students arrived at the experiment. In the instances where the experiment is conducted by only a Teaching Assistant (TA), the failure may not be brought to the classroom instructor’s attention and if it is, it is usually only after the class has struggled with the experiment and has given up on operating it during the time allotted for the lab and has left the lab for the next class. This unfortunate but, in the opinion of this author, inevitable incident is particularly grievice for engineering technology students whose classroom work and attentions are heightened by the laboratory experience. The need for the lab to compliment the classroom work compels the Instructor to reschedule the lab. But this rescheduling is often difficult if possible at all due to the extensive course schedule that is being maintained by the engineering technology student. The old adage about “...learning more from your mistakes” has an even more true (and longer) corollary that may be stated as: “Every failure is rife with opportunity to learn about the causes of the failure and the logical and rational diagnostic procedures that are employed to determine this cause typically results in the investigator in learning at an accelerated rate”. This paper presents the argument that the only satisfactory alternative P ge 11702.2 is to make use of the failure as an opportunity to teach the engineering technology student. Turning Lemons into Lemonade This paper was conceived after a recent thermodynamics experiment started badly but seemed to transform itself into a significant learning exercise for the students. The very net positive experience as expressed by the students provided the a revelation to the instructor that not only do “...you learn more from your mistakes” but also, perhaps these “mistakes” should be scheduled into the actual experiment to promote a more interesting experiment for the students; one that they can be more involved in than otherwise is the case for typical experiments. Consider the following incident. The student’s first class in thermodynamics has a scheduled lab experiment to emphasize the measurement of steam pressure and temperature, the vapor pressure-temperature relationship, and the measurement of steam quality using a steam throttling calorimeter. The piping and instrumentation diagram for the experimental apparatus is shown in Figure 1. The piping includes several parallel loops, valves, flow meters, water pump, condenser/fan assembly, a 3,000 watt electric steam boiler, power meters, thermocouple and pressure instruments and transducers. The purpose of the lab experiment is straight forward: to boil water at different pressures and record the pressure and temperature. Check the recorded temperature and pressure against the steam charts. The system also includes a throttling calorimeter that the student will use to measure the enthalpy of the steam as it exits the boiler. The instructor implores the students that they must first get thoroughly familiar with the test apparatus by tracing the piping and carefully redrawing the piping network. The students comply but are just a little more than going through the motions to get the drawing completed as quickly as possible. After all, the system is operating properly, isn’t it? The piping must be correct, the steam is being generated and carried through the piping to all of the correct destinations: valves, flow meters, condenser/fan assembly, etc.