Staying Afloat and Learning to Think BY JAC Q U ELI NE HA RTL I N G STO LZ E
IIHR alumnus Fred Locher has some good stories to tell about his student days at the institute.
Former IIHR Director Hunter Rouse’s Intermediate Fluid Mechanics course kept even the best graduate students in the 1950s and ’60s in awe, often tinged with fear. But it couldn’t be avoided — if you studied at the institute, you took the course. Rouse used the course to determine if the student was to be accepted for study for advanced degrees. As the legendary Rouse stood at the chalkboard, sketching fluid mechanics problems in his beautiful hand (“It was like watching the textbook being illustrated right in front of your nose,” remembers IIHR alumnus Fred Locher), most students were struggling just to stay afloat. What they feared was that Rouse would direct a question to them, a question that could seem deceptively simple. And thus deceived, they might answer incorrectly. Rouse would then lead them down this disastrous track until they reached a dead end from which they could not extricate themselves. It could happen to anyone, anytime. One day, the class was talking about jets. Rouse asked a seemingly simple question. You’ve got a drinking fountain out in the hall, Rouse said. When you first open the drinking fountain, the jet squirts up higher than it does when it finally settles down to steady state. Why is that? The student unlucky enough to be asked started confidently but wandered further and further into left field. Rouse let him continue until at last the student realized — he didn’t know why the fountain behaved that way. 2 4 • I I HR C U RRENTS
After watching the student flail about, Rouse asked more questions to encourage him to find a way out of his predicament. It was a harrowing experience, but an educational one, Locher says. “You’d put two and two together and come out of it,” he explains. “That was part of your education.” Locher, who earned MS and PhD degrees at IIHR in the 1960s, says he sat through Rouse’s course two more times after he passed it the first time. “The first time through, you were so busy trying to not fall in the hole,” Locher says. “There were guys who were just absolutely petrified in that course because it was an experience that you hadn’t had before. Also, your future at Iowa depended on passing Rouse’s evaluation.” Rouse, he says, insisted that students approach problems by asking themselves, what should that fluid be doing? “He wasn’t interested in teaching you mathematics. He was interested in the physical aspects of what you were seeing and what you would learn from what you saw,” Locher says. “He was trying to get people to think! In my experience, that is the most difficult thing to do.”
