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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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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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.
Noritoshi Minami, Toshiaki Chikusa, Michio Murase
Nuclear Technology | Volume 164 | Number 2 | November 2008 | Pages 265-277
Technical Paper | Thermal Hydraulics | doi.org/10.13182/NT08-A4025
Articles are hosted by Taylor and Francis Online.
Different flow patterns of steam forward flow and nitrogen reverse flow in U-tubes were observed in the reflux condensation experiments using the Bethsy facility with 34 U-tubes. In this study, the behavior was calculated using RELAP5/MOD3.2 with two and three flow channels of U-tubes. By the modification of the weighting factor for the calculation of friction coefficients, the nitrogen reverse flow was successfully calculated. In the calculations changing the flow area ratio of two flow channels, the number of active U-tubes with steam forward flow was predicted using the assumption that flow was most stable in the case with the maximum nitrogen recirculation flow rate, and it agreed rather well with the observed number of active U-tubes (19 to 24 U-tubes) within the difference of 4 U-tubes. In the calculations with three flow channels, without the assumption, the average of the ratios of active U-tubes in several calculations (four cases in this study) with different flow area ratios of the three flow channels gave good prediction of the ratio of active U-tubes. The results indicate the validity of the assumption that the flow with the maximum nitrogen recirculation flow rate may be the most stable and appear most probably among different numbers of active U-tubes.
