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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.
Dong Hun Lee, Dong-Ha Lee, Jae Jun Jeong, Kyung Doo Kim
Nuclear Technology | Volume 198 | Number 1 | April 2017 | Pages 79-84
Technical Note | doi.org/10.1080/00295450.2017.1287503
Articles are hosted by Taylor and Francis Online.
Frictional pressure drop (also called wall drag) for a two-phase flow has been investigated for several decades. However, the two-phase frictional pressure drop models in the state-of-the-art thermal-hydraulic system codes are significantly different from each other, especially in the way to partition the wall friction force of liquid and vapor phases in the two-fluid momentum equations. This may lead to unphysical results in some flow conditions.
In this technical note, the two-phase wall frictional pressure drop models in the RELAP5/MOD3, TRACE V5, and SPACE codes are discussed in terms of the wall friction partition into the liquid and vapor momentum equations. To show the effect of different partition methods in the three codes, we simulated air-water bubbly flows in a horizontal pipe. The results of the calculations show that the partition method has a direct effect on the relative velocity of the two phases, and it may lead to unphysical behaviors of dispersed bubbles and droplets. It is strongly recommended to revisit the two-fluid formulation and the partition method of two-phase wall drag in the state-of-the-art system codes.
