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Division Spotlight
Radiation Protection & Shielding
The Radiation Protection and Shielding Division is developing and promoting radiation protection and shielding aspects of nuclear science and technology — including interaction of nuclear radiation with materials and biological systems, instruments and techniques for the measurement of nuclear radiation fields, and radiation shield design and evaluation.
Meeting Spotlight
2025 ANS Annual Conference
June 15–18, 2025
Chicago, IL|Chicago Marriott 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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Smarter waste strategies: Helping deliver on the promise of advanced nuclear
At COP28, held in Dubai in 2023, a clear consensus emerged: Nuclear energy must be a cornerstone of the global clean energy transition. With electricity demand projected to soar as we decarbonize not just power but also industry, transport, and heat, the case for new nuclear is compelling. More than 20 countries committed to tripling global nuclear capacity by 2050. In the United States alone, the Department of Energy forecasts that the country’s current nuclear capacity could more than triple, adding 200 GW of new nuclear to the existing 95 GW by mid-century.
Sadi Kaya, Hasbi Yavuz
Nuclear Technology | Volume 129 | Number 1 | January 2000 | Pages 26-35
Technical Paper | Reactor Safety | doi.org/10.13182/NT00-A3043
Articles are hosted by Taylor and Francis Online.
For analyzing nuclear power reactor core transients, a three-dimensional nodal kinetics and thermohydraulics code, NOKTA, was developed. Nodal kinetics calculation is based on a one-group neutron diffusion approach. Thermal-hydraulics analysis is handled as in the COBRA-IV-I code. The NOKTA code was designed for analyzing especially large reactivity accidents, such as sudden rod ejection. It can also analyze intermediate transients, such as sharp power changes that may initiate xenon oscillations, and slow transients, such as boric acid density changes in the flow. The code dimensions are set at 125 subchannels and 30 axial levels. Calculation starts with a saturated xenon density, one-group neutronics parameters, and a flux profile, which is required as an input. Initially, keff of each computation cell is set to unity.
