SULI intern at ORNL hones skills in fusion reactor modeling, gains valuable experience ahead of graduate school Meet Jack Fletcher

Jack Fletcher has long been fascinated with nuclear technology. His grandfather, who worked as a nuclear engineer at a public utility company, inspired him to pursue a bachelor’s degree in nuclear engineering at the Missouri University of Science and Technology, where he is due to graduate in May 2022.

SULI intern at ORNL hones skills in fusion reactor modeling, gains valuable experience ahead of graduate school

Jack Fletcher prepares to take a measurement using modulated photothermal radiometry at the Missouri University of Science and Technology’s Materials Research Center. This device was developed to measure the surface thermal diffusivity of irradiated and non-irradiated materials. Fletcher recently participated in a summer internship at Oak Ridge National Laboratory, where he contributed to research efforts in nuclear reactor modeling. (Credit: Michael Pierce/Missouri S&T)

Through the Science Undergraduate Laboratory Internships (SULI) Program, Fletcher gained hands-on experience in nuclear reactor modeling at the U.S. Department of Energy (DOE)’s Oak Ridge National Laboratory (ORNL).

The SULI program, sponsored by the DOE Office of Science, Office of Workforce Development for Teachers and Scientists, encourages undergraduate students and recent graduates to pursue STEM careers by providing research experiences at DOE national laboratories. 

During his SULI internship, Fletcher was part of ORNL’s Thermal Hydraulics Group, within the Nuclear Energy and Fuel Cycle Division. Under the mentorship of Distinguished R&D Staff Member Vittorio Badalassi, Ph.D., and Nuclear Reactor Analyst Jin Whan Bae, Fletcher contributed to the Fusion Energy Reactor Models Integrator (FERMI) project. FERMI, funded jointly by DOE’s Office of Science and the Advanced Research Projects Agency-Energy, seeks to apply a suite of predictive simulation platforms to the challenges of designing the first generation of fusion reactors.

As part of this effort, Fletcher used Python programming techniques to develop and optimize the geometry of a model representing a proposed fusion reactor design. Such models will play an integral part in furthering the development of commercial fusion reactors.

“By accelerating the conceptual design process of fusion reactors, my project promotes the commercialization of a safe, efficient, carbon-free energy source,” Fletcher said. “Fusion and advanced fission technologies can provide the energy needed to continue innovating at ever-increasing rates, securing a better future for generations to come.”

Through his participation in the SULI program, Fletcher deepened his knowledge of neutronics and fusion reactor design. The research experience also introduced him to machine learning methods in reactor design applications.

“I found this internship to be very valuable,” Fletcher said. “I recommend the SULI program for the exposure it offered to cutting-edge research at one of the nation’s foremost laboratories, as well as for immersion in the culture of the lab through a wide variety of research fields.”

After graduating with his bachelor’s degree, Fletcher will begin a doctoral program in nuclear engineering at the Massachusetts Institute of Technology (MIT). He will conduct research in MIT’s Plasma Science and Fusion Center in support of the advancement and commercialization of fusion reactors.

His advice to fellow students? Don’t be afraid to seek out opportunities that interest you.

“Each of us has the potential to do something meaningful. As an early undergraduate, I sometimes believed contributing to the scientific community, or even interning at a national laboratory, was beyond my reach,” he said. “But through seeking out opportunities like SULI and becoming involved in professional societies, the chance to do so was there all along. Take the opportunities you’re given — even if you’re not sure you’ll succeed — because you may well surprise yourself, and the experience may lead to possibilities that shape the course of your career.”

The SULI program is sponsored by the U.S. Department of Energy, Office of Science, Office of Workforce Development for Teachers and Scientists. The program at ORNL is administered by the Oak Ridge Institute for Science and Education (ORISE).