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Division Spotlight
Accelerator Applications
The division was organized to promote the advancement of knowledge of the use of particle accelerator technologies for nuclear and other applications. It focuses on production of neutrons and other particles, utilization of these particles for scientific or industrial purposes, such as the production or destruction of radionuclides significant to energy, medicine, defense or other endeavors, as well as imaging and diagnostics.
Meeting Spotlight
International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2025)
April 27–30, 2025
Denver, CO|The Westin Denver Downtown
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Latest News
TerraPower begins U.K. regulatory approval process
Seattle-based TerraPower signaled its interest this week in building its Natrium small modular reactor in the United Kingdom, the company announced.
TerraPower sent a letter to the U.K.’s Department for Energy Security and Net Zero, formally establishing its intention to enter the U.K. generic design assessment (GDA) process. This is TerraPower’s first step in deployment of its Natrium technology—a 345-MW sodium fast reactor coupled with a molten salt energy storage unit—on the international stage.
Hugues W. Bonin
Nuclear Technology | Volume 76 | Number 3 | March 1987 | Pages 390-399
Technical Paper | Fuel Cycle | doi.org/10.13182/NT87-A33924
Articles are hosted by Taylor and Francis Online.
The optimization problem of the in-core fuel management of a thorium-fueled CANDU pressurized heavy water reactor (PHWR) consists of several component actions: the number of fresh fuel bundles inserted in the channels, the choice of the channels to be refueled next, the refueling rate, and the composition of the fresh fuel bundles (the latter relevant to advanced fuel cycles). Several fresh fuel compositions of 232Th and 233U were investigated and compared to the self-sufficient equilibrium thorium (SSET) cycle fuel, in terms of the objective function of an optimal fuel management problem. This optimization problem consisted of minimizing the total refueling rate at equilibrium with respect to criticality and power peaking constraints. The maximum acceptable value of the form factor was equal to 1.20, the form factor defined as the maximum-to-average power density ratio in the reactor core. The reactor core was divided into two refueling zones, each characterized by a uniform refueling rate for its channels. The control variables of the optimization problem were the average fluences (irradiations) of the bundles discharged from the channels of each of the zones, these variables being directly related to the refueling rates. A computer code, ASTERIX, was written to solve the optimization problem, using a steepest descent method, which required only a moderate number of diffusion calculations. Simulation was performed on simple models of a 600-MW CANDU PHWR. Because of the presence of 233Pa in the fuel, the diffusion calculations are nonlinear, needing a more complex solution technique. The cell parameters used were calculated by the Atomic Energy of Canada Limited code LATREP for a two energy-group model. This optimization technique gave optimal results that represent substantial savings in the refueling rates (up to 14%) when compared to nonoptimal feasible cases. The comparison of the various fuel compositions studied revealed that the sensitivity of the refueling rate (and the burnup) to the fresh fuel content is quite large for the SSET fuel and the low enrichment fuels.
