Yesterday I got to visit a chemical engineering classroom for the first time ever. It reminded me a lot of my old workplace, which was full of homemade reactors for synthesizing fullerenes and carbon nanotubes. I worked in the lab, not the plant, and was always in awe of those enormous, high temperature contraptions.
My guide yesterday was actually a co-op student at that company. We shared a going away party at the end of 2011. But when we worked together, chemical engineering major Ben Langhauser spent his time playing with nanotubes, whereas I hung out with fullerenes most of my days. I had no idea that the whole time he was with us, he was also planning for the regional ChemE Car Competition which took place on the 17th.
Northeastern’s team, which Ben captains this year, took home the awards for best performance and most creative car. The other students on the team were Aaron Lamoureux, Eric Corti, Tom Gillooly, Layal Ismail, Carly Gajewski, David Hurt, Theji Jayarante, and Amy Zhu.
So, if you’re like me (before Ben explained it) and have no clue what a ChemE Car Competition is, here’s the deal: Every year there are 9 regional competitions throughout the country, where students at various colleges and universities race a chemically-powered car they’ve designed and built. The winners from each race go on to compete in a national competition, which will be held in Pittsburgh this fall.
An hour before the race, the students learn how far their car must travel and how much extra weight (in water) it must carry. At this year’s Northeast Regional Conference, which was hosted by the University of New Haven, the cars had to get as close to 82 feet as possible while carrying 300mL of water.
At this year’s competition, Ben told me, there were only three designs among the eight teams. Northeastern’s design was one-of-a-kind — hence the most creative award. The car was created completely from scratch, including elements like a custom-made aluminum chassis, a couple of pressure vessels containing sodium bicarbonate and acetic acid (baking soda and vinegar), a solenoid valve, and – my favorite – a 4 cylinder LEGO pneumatic engine (!!!).
As you may remember from elementary school volcano demonstrations, baking soda and vinegar react to form carbon dioxide. One of the two pressure vessels contains a ready-made mixture of these compounds and is pressurized to 170psi with the gas produced in the reaction. “This powers the pneumatic engine which turns the axle through a pair of timing belts,” Ben explained.
A separate pressure tank contains only baking soda. At the start of the race,vinegar and some amount of water (depending on the distance the car needs to travel) are added to the tank. When the pressure in this tank is below 15psi, the solenoid valve is open. When the pressure reaches 15psi, the solenoid valve closes via a pressure switch, causing the motor to stop running and the car to stand still.
To make sure the car would run 82 feet with extra weight, the team had to do a few calculations before the race. They had to determine how much acetic acid/water to add in order for the car to travel as close to 82 feet as possible. They did a pretty good job, apparently, because the car went only 5.5 feet over (and thankfully the competition doesn’t follow Price Is Right rules). This was the closest of all the cars.
Ben said that being involved with the ChemE car team was not like any old class lab — “It’s totally student run,” he said, noting that Professor Courtney Pfluger was always around for advice if they needed it. “We had to come up with the design, we had to figure out how to run it, what tests to run. Basically we had to come up with the experimental procedure.” It gave him experience in things like safety regulations (he had to submit a 50 page safety document before they could participate), budget management and high pressure systems.
Here are a couple of videos for your viewing pleasure. First is the video of Ben’s team winning the competition, then a video I recorded with my phone of Ben running the car in a Mugar hallway.