Nuclear modelling

Rensselaer Polytechnic Institute is leading a $3m research partnership funded by the US Department of Energy to create highly detailed computer models of a new type of nuclear reactor.

These models could play a key role for the future development of the new reactors, which meet stringent safety and nonproliferation criteria, can burn long-lived and highly radioactive materials, and can operate over a long time without using new fuel.

To undertake such a task, researchers will use both Rensselaer’s Computational Center for Nanotechnology Innovations, or CCNI - the world’s seventh most powerful supercomputer - and Brookhaven National Laboratory’s New York Blue - the world’s fifth most powerful supercomputer.

Rensselaer nuclear engineering and engineering physics Prof Michael Podowski is the project director and principal investigator of the new study. Along with Rensselaer and Brookhaven, he will work with researchers from Columbia University and the State University of New York at Stony Brook.

The type of reactor that Podowski’s team will be modelling - a sodium-cooled fast reactor (SFR) - has the advantage that it can burn highly radioactive nuclear materials, which today’s reactors cannot do.

Whereas current reactors source their power from uranium, SFRs can also source their power from fuel that is a mixture of uranium and plutonium. In particular, SFRs will be able to burn both weapons-grade plutonium and pre-existing nuclear waste, Podowski said. Thanks to their high temperatures, SFRs will also produce electricity at higher efficiency than current nuclear reactors.

Along with producing less toxic waste, SFRs should be able to actively help reduce the amount of existing radioactive materials by burning already-spent nuclear waste. SFRs also offer a way to eliminate the world’s stockpile of weapons-grade nuclear fuel.

Podowski’s team will construct a detailed computer model of an SFR and simulate fuel performance, local core degradation, and fuel particle transport. By better understanding how design and operational issues will affect the reactor at different stages in its life cycle, the new study will help to improve the design and safety of SFRs long before the first physical prototype is ever built.