Goal of Almost Limitless, Clean Energy Attracts Creative Minds
Fusion, the same energy source that powers the sun and the stars, offers the potential to provide the planet with a nearly unlimited source of energy. To be a part of this massive endeavor—which is one of the 14 Grand Challenges for Engineering sponsored by the National Academy of Engineering—is an attractive draw for young aspiring engineers like Shawn Zamperini.
With a background in physics from the University of Virginia, Zamperini came to UT’s Department of Nuclear Engineering to study under Associate Professor David Donovan, relishing the chance to dive deep into physics research while advancing the aims of fusion technology. Now a doctoral graduate, Zamperini’s research experience will send him straight to work with DIII-D National Fusion Facility.
“Shawn has done an excellent job combining measurements collected at a world-leading fusion experiment with state-of-the-art theoretical models,” said Donovan, his advisor. “His ability to ask important and interesting questions and his hard work developing solutions make him a great scientist, and I am very proud that he will be representing UT’s fusion program in his new career.”
With the help of students like Zamperini, UT’s fusion program is making waves in the nuclear engineering industry. Zamperini’s research takes a closer look at a phenomenon that has, until now, only been hypothesized. For almost four decades, nuclear engineers presumed that the plasma at the edge of the fusion reactor core accumulates impurities from the core.
Engineers are interested in observing impurity transport in the edge of the plasma in order to identify the path impurities take before entering and contaminating the core plasma. Zamperini’s thesis provides the first indirect measurement of tungsten (an impurity) accumulation in the edge of the plasma through the use of specially machined graphite rods.
The graphite rods are designed and built by the department and are now in demand by other facilities. When stuck into the edge, impurities like tungsten deposit onto them, where the amount of tungsten is subsequently measured and analyzed at facilities like Oak Ridge National Lab (ORNL) and Sandia National Lab. The measurements for Zamperini’s thesis were taken with a high-resolution mass spectrometry system at ORNL that was brought online through a collaborative project between ORNL scientists and UT student researchers.
“The rod has two sides, and we can see which side collects more,” he said. “It tells us which direction the impurities are arriving from, and with the help of large-scale simulations, that the measurements only make sense if impurities are accumulating at the edge of the plasma.”
At DIII-D, Zamperini will work as a staff scientist in the advanced materials evaluation group, which is the same group he worked with when he did his research. UT’s close working relationship with the group enabled him to skip the typical postdoctoral research term and go straight to staff scientist.
Those who work in fusion say it is the Holy Grail of clean energy because it has the capacity to power industry, which requires more power than what renewables currently offer. If all goes as planned, fusion should be viable by the 2040s, though some private startups hope to achieve the goal sooner.