9/22/2010

Grad student examines nuclear materials safety

Graduate student Stephanie Pitts. (Photo by Michelle White, School of
Mechanical & Materials Engineering)

A $150,000 three-year fellowship is charting the way for Stephanie Pitts, a Ph.D. student in mechanical engineering, to conduct research on stainless steel used for nuclear power plant construction.
 
Pitts will be working with Hussein M. Zbib, professor and director of the School of Mechanical and Materials Engineering, to study how stainless steel reacts under radiation.
 
"What I do is important because most nuclear power plant buildings are made of this material,” she said.
 
The Nuclear Energy University Programs of the U.S. Department of Energy (DOE) awarded the fellowship to 30 graduate students studying nuclear science or a related engineering field in August 2010.
 
The DOE and the Generation IV International Forum are designing six experimental nuclear energy systems to employ a variety of novel reactor, energy conversion and fuel cycle technologies. These reactors are studied to determine resistance against proliferation threats and robustness against sabotage and terrorism threats.
 
Some of the concepts include a very fast nuclear reactor that operates at a high temperature, a system that uses molten sodium to cool the plant instead of water, and a closed system that recycles nuclear material until it isn’t radioactive, Pitts said.
 
Her research is focused on using computational analysis to determine how safe the proposed new technologies and designs would be.
 
"At some point in time, the material will change so much that it will be unsafe for a particular design,” she said. "You want a model that will accurately predict when it is time to replace the material.”
 
Other than testing materials, Pitts also wishes to alter the stereotype of nuclear energy by promoting its environmental friendliness. Unlike the combustion of fossil fuels, which produces most of the world’s electricity, nuclear power does not produce carbon dioxide or contribute to climate change.
 
"Whenever you say nuclear energy, the public thinks of Hiroshima and Nagasaki,” she said. "But the actual creation of radioactive elements doesn’t burn anything, so it doesn’t release anything in the air - there isn’t any excess carbon.”
 
One example she cited is a small sealed nuclear reactor at the Model United Nations Conference held in New York in April 2010. This reactor could be taken to Africa and plugged into the electric grid to provide power to smaller cities. It is also described as "tamper resistant" against terrorism threats.
 
"I like this idea because it offers an example of using nuclear power for greater good in contrast to the power of destroying the world,” she said. "It’s great to see nuclear energy used for peaceful purposes like human technology and sustainability.”
 
After graduation in 2013, Pitts plans either to enter the academic field or pursue a career at a national lab such as Sandia, Los Alamos or Oakridge.
 
She also is interested in working for an organization called PONI (Project on Nuclear Issues) that creates a network community for young nuclear experts by mentoring and integrating them into public debate on all issues concerning nuclear weapons.