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Conference Spotlight
2025 ANS Winter Conference & Expo
November 9–12, 2025
Washington, DC|Washington Hilton
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The journey of the U.S. fuel cycle
Craig Piercycpiercy@ans.org
While most big journeys begin with a clear objective, they rarely start with an exact knowledge of the route. When commissioning the Lewis and Clark expedition in 1803, President Thomas Jefferson didn’t provide specific “turn right at the big mountain” directions to the Corps of Discovery. He gave goal-oriented instructions: explore the Missouri River, find its source, search for a transcontinental water route to the Pacific, and build scientific and cultural knowledge along the way.
Jefferson left it up to Lewis and Clark to turn his broad, geopolitically motivated guidance into gritty reality.
Similarly, U.S. nuclear policy has begun a journey toward closing the U.S. nuclear fuel cycle. There is a clear signal of support for recycling from the Trump administration, along with growing bipartisan excitement in Congress. Yet the precise path remains unclear.
Seungmin Oh, Haijing Gao, Shripad T. Revankar
Nuclear Technology | Volume 158 | Number 2 | May 2007 | Pages 208-218
Technical Paper | Nuclear Reactor Thermal Hydraulics | doi.org/10.13182/NT07-A3836
Articles are hosted by Taylor and Francis Online.
An experimental study and best-estimate thermal-hydraulic code model assessment is performed to investigate the characteristics of the filmwise condensation with and without noncondensable gas in a passive condenser system. A vertical condenser tube is submerged in a water pool, where the heat from the condenser tube is removed through boiling heat transfer. Data are obtained for various inlet steam flow rates and noncondensable gas mass fractions at various system pressure conditions for two tube inner diameters: 26.6 and 52.5 mm. Experimental data are compared with analysis for complete condensation and flow-through conditions. Degradation of the condensation with noncondensable gas is investigated, where the condensation heat transfer coefficient decreases with the noncondensable gas. Experimental results are simulated with the RELAP5 code using two different condensation models. Code predictions are compared with experimental data, and the results indicate that there is a need for improved condensation models in RELAP5.
