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NC State celebrates 70 years of nuclear engineering education
An early picture of the research reactor building on the North Carolina State University campus. The Department of Nuclear Engineering is celebrating the 70th anniversary of its nuclear engineering curriculum in 2020–2021. Photo: North Carolina State University
The Department of Nuclear Engineering at North Carolina State University has spent the 2020–2021 academic year celebrating the 70th anniversary of its becoming the first U.S. university to establish a nuclear engineering curriculum. It started in 1950, when Clifford Beck, then of Oak Ridge, Tenn., obtained support from NC State’s dean of engineering, Harold Lampe, to build the nation’s first university nuclear reactor and, in conjunction, establish an educational curriculum dedicated to nuclear engineering.
The department, host to the 2021 ANS Virtual Student Conference, scheduled for April 8–10, now features 23 tenure/tenure-track faculty and three research faculty members. “What a journey for the first nuclear engineering curriculum in the nation,” said Kostadin Ivanov, professor and department head.
E. Dumonteil, T. Courau
Nuclear Technology | Volume 172 | Number 2 | November 2010 | Pages 120-131
Technical Paper | Reactor Safety | dx.doi.org/10.13182/NT10-A10899
Articles are hosted by Taylor and Francis Online.
Typical dimensions of large neutronic systems are often two orders of magnitude greater than the mean free path of the neutrons. Such high dominance ratio systems represent a particularly challenging issue when performing Monte Carlo criticality simulations. As a matter of fact, these simulations are contaminated by a cycle-to-cycle correlation that strongly slows down the flux convergence. In this paper, we will first discuss the link between the dominance ratio and the cycle-to-cycle correlations that are responsible for the poor flux convergence. Then, we will present a new and original technique to assess the dominance ratio of a given Monte Carlo simulation. It consists of fitting the relaxation process of the neutron field after an initial excitation from a fission source with a Dirac delta function shape. Having showed that these flux convergence issues are dominance ratio driven, we will then propose the use of an "independent replicas" approach to deal with the underprediction bias in statistics. The different theoretical points presented in this paper will be verified on a pin cell test case simulated with the Monte Carlo code TRIPOLI4. Additional results based on a three-dimensional pressurized water reactor core calculation are provided to confirm the reliability of the fitting technique described.