Mechanical engineer Paul Millett is leading a study on strategies to minimize swelling in metallic nuclear fuels as a way to improve the safety and efficiency of nuclear reactors.
“Almost all current nuclear energy reactors operate with ceramic fuels,” Millett said. “But as an alternative, metallic fuels have generated significant interest because they have much higher thermal conductivity, meaning the temperatures in the reactor are far lower than with ceramic fuels.”
Fuels in metallic form, however, have a tendency to swell significantly during operation, which limits the efficiency of power generation. The swelling is a caused by gas elements such as helium and xenon that are produced by the atomic fission process and cluster to form gas-filled bubbles within the fuel.
Millett is the principal investigator on the $786,407 grant from the U.S. Department of Energy. He will work with researchers at the Georgia Institute of Technology, Texas A&M University and the Idaho National Laboratory, using advanced computer simulations and experiments to get a better understanding of the micro-scale processes that lead to volumetric swelling in metallic fuels.
Most importantly, the researchers will explore how to design fuels that are resistant to swelling.