Modeling the future of Nuclear Energy
NC State researchers use advanced computer simulations to create safer, more cost-effective nuclear power plants.
Dr. Paul Turinsky does not like CRUD.
It's the nasty buildup of corrosive products on fuel rods inside nuclear reactors that, if left unmanaged, can lead to nuclear authorities "derating" plants. That means the plants aren't allowed to produce as much energy as before for safety reasons.
As chief scientist of the Consortium for Advanced Simulation of Light Water Reactors (CASL), Turinsky wants to make sure that future reactors can work safely and more efficiently. CASL, a unique collaboration between universities, laboratories and industry, develops advanced computer models that will help engineers design the next generation of nuclear reactors and improve the performance of current ones. The team is working on making nuclear power more economical, reducing the amount of nuclear waste and assuring safety.
NC State, which built and operated the first university-based nuclear reactor in the world in 1953, plays a key leadership role in the $122 million Department of Energy (DOE)-funded effort that began in 2010. NC State researchers working with CASL have academic and industry experience in fields ranging from computational science to nuclear engineering.
"There's a lot of talent on this campus," said Turinsky, a nuclear engineering professor. "I want to get as much breadth of expertise involved as I can because nuclear engineers don't know everything that needs to be done."
There are 104 nuclear power plants operating in the United States that supply 20 percent of the nation's electricity. After a decades-long shift away from nuclear power in this country, a few new plants will finally come online by 2020.
CASL's work will help shape the industry in the coming decades. Its research will provide nuclear engineers with the most up-to-date information needed to build and operate safe and cost-effective reactors. This includes finding ways to stay one step ahead of what's known as CRUD, formally known as Chalk River Unidentified Deposits (a reference to the Canadian nuclear plant where the buildup was first observed).
"Think of boiling a pan of water after the liquid has evaporated, leaving a film of solids coating the pan," Turinsky said. "We're dealing with that buildup constantly."
Finding ways to limit CRUD safely and inexpensively is one of CASL's toughest technical modeling challenges.
Led by Oak Ridge National Laboratory, DOE's largest science and energy laboratory, CASL consists of 10 core partners and more than a dozen contributing partners. The wide range of partners and facilities has its perks. Oak Ridge and Los Alamos National Laboratory, for example, have some of the fastest computers in the world for doing computer simulations and modeling.
CASL's work focuses on current Generation II reactors and Generation III+ pressurized water reactors, which differ from the ones at Japan's Fukushima Daiichi plant that were damaged in the earthquake and tsunami last year.
For those reactors, plant operators relied on back-up generators to safely shut the reactor down. The new Generation III+ reactors don't use back-up generators, which are no longer required, and can safely function for longer periods of time if there's a complete loss of electrical power. Also, like all nuclear plants, they have automatic systems that shut the plant down safely in the event of an emergency.
To design the next round of nuclear reactors and enhance the performance of current ones, engineers are gearing up to work with a collection of CASL-produced advanced modeling and simulation tools known as the Virtual Environment for Reactor Applications (VERA).
"We're building a monster code that simulates nearly all the phenomena involved," Turinsky said.
VERA will allow engineers to test nuclear reactor designs using computer simulation, avoiding the safety issues and costs associated with performing real-world experiments. CASL researchers will have the tools to simulate coolant flow, fuel performance and other scenarios that are hard to observe in operating reactors.
To use VERA, however, the nuclear engineering students of tomorrow will need general knowledge of everything from mechanical engineering to materials science to reactor physics.
Dr. John Gilligan, CASL's education program coordinator, helps recruit top students into the program to get the exclusive training on the VERA system.
"The kind of expertise they get here can be applied anywhere in the world," said Gilligan, a professor of nuclear engineering.
One of CASL's students, Sterling Satterfield, is working with Turinsky to gain a better understanding of reactor simulation. He's using a concept called Adaptive Model Refinement that allows researchers to apply simple modeling techniques in some situations and more complicated ones in others. Knowing when to use each model and how to combine the results allows researchers to spend less time running simulations, saving time and money.
He learned that from Turinsky.
"I got the opportunity to work with Dr. Turinsky — the best of the best," Satterfield said. "That's one of the main reasons I came to NC State."