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Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
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
Conference on Nuclear Training and Education: A Biennial International Forum (CONTE 2025)
February 3–6, 2025
Amelia Island, FL|Omni Amelia Island Resort
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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Reboot: Nuclear needs a success . . . anywhere
The media have gleefully resurrected the language of a past nuclear renaissance. Beyond the hype and PR, many people in the nuclear community are taking a more measured view of conditions that could lead to new construction: data center demand, the proliferation of new reactor designs and start-ups, and the sudden ascendance of nuclear energy as the power source everyone wants—or wants to talk about.
Once built, large nuclear reactors can provide clean power for at least 80 years—outlasting 10 to 20 presidential administrations. Smaller reactors can provide heat and power outputs tailored to an end user’s needs. With all the new attention, are we any closer to getting past persistent supply chain and workforce issues and building these new plants? And what will the election of Donald Trump to a second term as president mean for nuclear?
As usual, there are more questions than answers, and most come down to money. Several developers are engaging with the Nuclear Regulatory Commission or have already applied for a license, certification, or permit. But designs without paying customers won’t get built. So where are the customers, and what will it take for them to commit?
E. Kujawski, R. Protsik
Nuclear Technology | Volume 41 | Number 1 | November 1978 | Pages 36-45
Technical Paper | Reactor | doi.org/10.13182/NT78-A32131
Articles are hosted by Taylor and Francis Online.
A practical method for self-shielding resonance cross sections for fast reactors with complex heterogeneity results in a multiregion equivalence relation that is identical in appearance to the conventional two-region equivalence relation. The effects of heterogeneity are accounted for in terms of material- and region-dependent escape cross sections. The escape cross sections are explicitly given in terms of the first-flight collision probabilities or transport coefficient. The formulation is well suited for use with the shielding factor method. A detailed validation of the heterogeneity calculations with the proposed formulation has been carried out for plate-type cells, and good agreement with Monte Carlo results has been obtained. Sensitivity studies were performed to compare the proposed multiregion heterogeneity treatment with conventional two-region treatments. The results suggest that it may be important to self-shield explicitly and heterogeneously all the fuel and structural materials in the analysis of fast critical assemblies.
