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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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NN Asks: What did you learn from ANS’s Nuclear 101?
Mike Harkin
When ANS first announced its new Nuclear 101 certificate course, I was excited. This felt like a course tailor-made for me, a transplant into the commercial nuclear world. I enrolled for the inaugural session held in November 2024, knowing it was going to be hard (this is nuclear power, of course)—but I had been working on ramping up my knowledge base for the past year, through both my employer and at a local college.
The course was a fast-and-furious roller-coaster ride through all the key components of the nuclear power industry, in one highly challenging week. In fact, the challenges the students experienced caught even the instructors by surprise. Thankfully, the shared intellectual stretch we students all felt helped us band together to push through to the end.
We were all impressed with the quality of the instructors, who are some of the top experts in the field. We appreciated not only their knowledge base but their support whenever someone struggled to understand a concept.
Rohan Biwalkar, Kenneth Redus, Adam Stein, Sola Talabi
Nuclear Science and Engineering | Volume 197 | Number 8 | August 2023 | Pages 2099-2116
Technical papers from: PHYSOR 2022 | doi.org/10.1080/00295639.2023.2204174
Articles are hosted by Taylor and Francis Online.
The current study describes a simulation-based analysis of the atmospheric dispersion of radionuclide fission product particles in the near-field and far-field of a generic, conceptual microreactor, which is a small nuclear reactor with a power output typically ranging from 1 to 20 MW(thermal) and generally lower than 50 MW(electric). The near-field is a distance of up to 100 m from the microreactor while the far-field is a distance of 300 m or beyond from the microreactor. The generic microreactor operates at a pressure close to the ambient pressure. Therefore, in the event of a postulated accident that causes the leakage of radionuclide particles from the microreactor containment into the environment, the radionuclide particles are unlikely to travel too far from the reactor, as opposed to conventional nuclear reactors. The current paper provides estimates of average and 95th-percentile values of the normalized effluent concentration of the atmospheric radionuclide particle dispersion with respect to the source strength in the near-field and far-field of the conceptual microreactor. The computer code Atmospheric Relative CONcentrations in Building Wakes (ARCON96) was used to perform all simulations for the current study. It was observed that the 95th-percentile values of the normalized effluent concentration decrease by an order of magnitude as the receptor distance increases, i.e., from the near-field to the far-field. The dispersed aerosol concentration also decreases with time. A parametric study was performed to understand which input parameters affect the normalized effluent concentration values the most, and a definitive screening design was employed for this purpose. The atmospheric stability class and the distance between the reactor and the receptor were the parameters found to affect the aerosol dispersion characteristics by the greatest extent. The study recommends that the computer code RADTRAD (Radionuclide Transport and Removal And Dose Estimation) be used to estimate the actual dosage over distance using the outputs from ARCON96 as inputs, along with reactor-specific core inventories.
