The United States has about 104 commercial fission reactors producing approximately 19% of our electricity. Our nuclear systems engineering research programs are largely devoted to advancing the state of the art in technologies used to produce electricity from fission. Some of our key programs are described below.
Fission reactor safety
If we are to have a viable commercial nuclear energy fleet, we must be able to understand the behavior of a reactor under all operating conditions. Professors Corradini, Anderson, Bonazza, and Scarlat have extensive experience modeling reactors from a safety perspective as well as in experiments for validating the models.
The neutrons and charged particles inevitably present in nuclear facilities can do significant damage to structural materials. Atoms are displaced, properties are modified, and structures are deformed. We must understand these phenomena in order to produce viable reactor designs and understand component lifetime issues. Professors Allen, Kulcinski, Blanchard, Sridharan, Szlufarska and Morgan have experimental and computational programs to study the physics of these radiation damage events and the subsequent effect on reactor design.
Computational nuclear engineering
As simulation takes a larger role in the development of nuclear technology, there is a need to improve the fidelity and complexity of the simulations. With a focus on radiation transport and nuclide inventory tracking — and coupling these to other domain physics — Professors Wilson, Henderson and Tautges are delivering new simulation capability by combining modern computational science technology with new solution methodologies. These tools are being used to design complex systems like ITER, to improve radiation treatment planning, to understand next generation reactor designs, and to explore the science-policy boundary of advanced fuel cycles.
As we look to the future, reactors will tend to operate at higher temperatures in order to increase the efficiency of the energy conversion processes or to produce process heat for industrial applications such as hydrogen production. This leads us to the use of new coolants and materials and the need for ensuring that these combinations are compatible. Professors Allen, Sridharan, and Anderson all operate a variety of experiments that test the compatibility of coolants such as lithium, lead and aqueous salts with new, high temperature structural materials.
Radioisotope power sources
Radioisotope power sources convert the energy released during radioactive decay into electricity. Pacemakers were made years ago using this technology, in order to take advantage of their long lives and avoid the surgery needed for battery replacement. NASA also uses such sources in its space probes, in order to permit long, unattended missions. Professors Blanchard and Ma have studies several concepts for the production of modern nuclear batteries.