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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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Nuclear Science and Engineering
May 2025
Nuclear Technology
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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.
Cornelis H. M. Broeders
Nuclear Technology | Volume 71 | Number 1 | October 1985 | Pages 96-110
Technical Paper | Fission Reactor | doi.org/10.13182/NT85-A33712
Articles are hosted by Taylor and Francis Online.
The incentive of the Kernforschungszentrum Karlsruhe (KfK) advanced pressurized water reactor (APWR) investigations is the improvement of uranium utilization in a modem Federal Republic of Germany pressurized water reactor (PWR) by replacement of the core with a high converting one. The high conversion ratio is obtained by using mixed oxide (UPu)O2 in a tight light-water-moderated triangular lattice. The harder neutron spectrum leads to higher conversion ratios, to higher fissile enrichment and fissile inventories, and to worse reactivity behavior after coolant density changes. That means that core modification of the PWR shifts its neutron physics properties in the direction of fast reactor characteristics. The analysis of available calculational methods for fast and thermal reactors showed that neither the WIMS/D code, reliable for thermal reactors, nor the approved KAPROS fast reactor code can adequately predict the reactivity of an APWR in all configurations between normal and a totally voided core. A newly developed procedure, KARBUS, within the KAPROS fast reactor code system combines the advantageous features of thermal and fast reactor calculational methods. The preliminary validation for fast, epithermal, and thermal lattices, including burnup behavior, indicates that KARBUS is an adequate tool for the APWR investigations at present. Improvements in the detailed analysis of a final APWR design and of APWR neutron physics experiments in progress are briefly discussed. Parametric calculations for a simplified model indicate that current KfK proposals for homogeneous and heterogeneous APWR cores are nearly optimum concerning the competitive properties conversion ratio and void effect in a critical core poisoned by reactor control or by fission products.
