Vision Quest
In September 2006, Marquette University engineering professor Mark Polczynski challenged a team of five students as they began their senior project: Can you design a biodiesel reactor that's high tech, yet so ingeniously simple that you could imagine one on every farm, or in every village in India?
Mark Johnson of the Milwaukee Journal Sentinel followed the students through the school year as they tried to build the reactor, which would convert vegetable oils into fuel. His resulting series, "Green Machine: The Making of Biodiesel and Engineers," introduces readers to shirtsleeve science while telling a larger story about young people coming of age. Here's an excerpt in which the students perform a crucial test:
They began retesting the time it took water to drain from the small to the large tank. The controller had been programmed to switch from one function to another based on precise time measurements for each stage of the process. It was supposed to take 21 seconds for the liquid to drain.
On the first test, it took 24 seconds, then 21, then 50, then 27.
"Not good," Billy said.
They peered inside the small tank. Instead of flowing straight down, the water was swirling in a vortex like a flushing toilet. They had recently changed the pipe between the two tanks to a more flexible material. The small effort to make the reactor better appeared to have backfired and altered the water flow.
"God this sucks," Jamie said.
In Polczynski's view, this small, vexing problem offered a lesson on the new global economy.
"This is absolutely typical of the environment these guys are going to end up in," he said. "You have a relatively complex system, and you have different teams working on different elements of the system. These guys are working on the control system. Bill is working on the fluid flow. These guys have a fluid flow problem that has nothing to do with their controls."
Problems of this kind, he said, "are happening at this moment in 100,000 places in the world, and it's only going to increase with more globalization."
Jamie got an idea. He grabbed a small, ancient blower and unscrewed its metal grate. He bent the grate into a right angle and placed it in the bottom of the tank. This time the water drained. No swirling.
The $27 filter and flexible piping had made the reactor worse. A bent metal grate had made it better.
http://www.jsonline.com/biodiesel