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Division Spotlight
Nuclear Installations Safety
Devoted specifically to the safety of nuclear installations and the health and safety of the public, this division seeks a better understanding of the role of safety in the design, construction and operation of nuclear installation facilities. The division also promotes engineering and scientific technology advancement associated with the safety of such facilities.
Meeting Spotlight
Nuclear and Emerging Technologies for Space (NETS 2025)
May 4–8, 2025
Huntsville, AL|Huntsville Marriott and the Space & Rocket Center
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
First concrete marks start of safety-related construction for Hermes test reactor
Kairos Power announced this morning that safety-related nuclear construction has begun at the Oak Ridge, Tenn., site where the company is building its Hermes low-power test reactor. Hermes, a scaled demonstration of Kairos Power’s fluoride salt–cooled, high-temperature reactor technology, became the first non–light water reactor to receive a construction permit from the Nuclear Regulatory Commission in December 2023. The company broke ground at the site in July 2024.
Matjaz Ravnik, Tomaz Zagar, Andreja Persic
Nuclear Technology | Volume 128 | Number 1 | October 1999 | Pages 35-45
Technical Paper | Fuel Cycle and Management | doi.org/10.13182/NT99-A3012
Articles are hosted by Taylor and Francis Online.
Calculations of fuel element burnup for realistic mixed core conditions in a 250-kW TRIGA Mark II reactor are presented. Two types of fuel elements are considered: 70% enriched FLIP and 20% enriched standard fuel elements. Two calculation models are compared. The first is based on a one-dimensional two-group diffusion approximation (the TRIGAP computer code), and the second is based on a two-dimensional four-group diffusion equation (the TRIGLAV computer code). In both cases the unit-cell group constants are generated with the WIMS code. Results of the calculations are intercompared to evaluate the influence of the two-dimensional effects on fuel element burnup. The following two-dimensional effects are considered: mixed rings, in-core water gaps, vicinity of control rods, and asymmetric core loading patterns. Relative differences in fuel element burnup of 10% on average and up to 80% in extreme cases are observed because of the two-dimensional effects. The accuracy of the calculation is estimated also by comparing the calculated results to the measurements using the reactivity method.
