Ten University of Idaho students worked with the College of Engineering and NASA to develop an efficient energy storage system for their senior design project and presented their work Wednesday.
Joe Law, a UI professor and the principal investigator, said the project started when NASA requested research proposals for technology that would aid future lunar colonization.
“We looked at it and said, ‘Energy is essential. Other things you may or may not need for life support,'” Law said. “It was something that really resonated with the people at (NASA Glenn Research Center) because they looked at it and said ‘this is what we’re working on — we like where you’re headed.'”
UI was one of five universities chosen by the NASA Ralph Steckler Research and Technology Grant program, which awarded UI $70,000 to develop a reliable, efficient flywheel.
Law said the heavy integration of students into the process caught NASA’s attention.
“A lot of the teams didn’t understand that there was an educational focus as well as the technical,” Law said. “Our students … were excited about the program.”
The flywheel
A flywheel is a mechanical energy storage device that converts electrical energy into a spinning wheel, and then back into electrical when it’s needed. For lunar colonization, the day and night cycles, which produce a 354-hour night, require that solar energy gathered during the day can be stored for the night.
Juliet Petersen, a UI senior in electrical engineering, focused on the physical design of the device — where the wires would be, how many and the energy flow, she said.
The 2010-2011 team worked on lowering energy loss but the machine that was unable to produce accurate results.
“So what we’re doing is building a more efficient flywheel that’s tailored for testing their system, in a way they couldn’t on other machines,” Petersen said.
Energy can be lost through friction and wind resistance, but also through magnetism because a magnetic field starts the wheel rotating.
“What you end up doing is, normally, the crystals in the iron are all scattered — they’ve got little crystals that face all kinds of different ways,” Petersen said. “But when you rotate the machine in one direction, the crystals in the iron all get oriented in one direction.”
When the magnetic field is turned off and the flywheel is left to spin, the aligned crystals turn the wheel into a magnet.
“If you think about trying to spin a magnet,” Petersen said. “If you had a magnet here and a magnet here — it’s gonna have a preference of locking in one position.”
Their design will continue to send electrical signals to balance the magnetic field and keep the wheel spinning evenly. Peterson said the bursts take less energy than would be wasted by magnetic field.
To reduce friction, graduate students Kysen Palmer and Chris Mirabzadeh worked on a magnetic levitation system that would allow the wheel to freely spin in a vacuum.
They used a combination of a magnet and a “high-heat” superconductor the temperature of liquid nitrogen, -321 Fahrenheit, to float the wheel in place.
Mirabzadeh, a physics major, said the chilled superconductor is chilled repels all magnetic fields.
“It’s completely exclusive — it wants them all away and defects inside the superconductor grab field lines and create that pinning effect,” Mirabzadeh said.
Mirabzadeh used a bowl of liquid nitrogen, a small magnetic disk and a disk of the carbonate superconductor to show the process in action.
The silvery disk of the magnet floated an inch above the dark base, and when Mirabzadeh lifted it into the air with tongs, the superconductor followed it up — still about an inch below the magnet.
Kevin Ramus was involved with the electrical systems and sensors to keep the wheel spinning around the center without contacting it — with about a millimeter of room on either side.
“My job was to look at the design of the machine and say ‘how’re we going to make it work,'” Ramus said. “When a current passes through these (wires), it hops from this metal (center) to the rotor.”
Sensors and electric pulses keep the wheel centered.
“So we could adjust the energy levels in here to pull it back,” Ramus said.
Ramus said the team had to learn what a flywheel was coming into the project.
“No one had any clue what a flywheel was — how the inside-out machine was going to work, how we were levitating it — it was a steep learning curve,” Ramus said. “Once we got our heads wrapped around it, we stated making decisions on the dimensions and how are things going together.”
Petersen said the experience of starting from scratch helped her grow as an engineer.
“For the first time ever, we’re having to come up with our own specifications'” Petersen said.
“Before, they just told us ‘design something,’ or do this homework problem: X, X, X, Y. One unknown, one equation. But now we’re trying to figure out our specifications and do the design and prove a concept all in one.”
Ramus said he is coming back as a graduate student to keep working on the project.
“I started working on it and I was really exited about what I was doing,” Ramus said. “Whenever I start something, I want to see it happen.”
Joanna Wilson can be reached at [email protected]